Dissertations / Theses on the topic 'Albatross'

Personalen på barnavdelningen Albatross, Karolinska Universitetssjukhuset i Huddinge har känt av ett behov av att på ett användarvänligt och lättåtkomligt sätt komma åt information om antalet lediga och upptagna rum på avdelningen. Förslag på en visuell digital lösning till avdelningen skulle kunna bidra till att skapa effektivare arbete. Karolinska Universitetssjukhuset har för nuvarande ingen lösning för att uppfylla detta behov. Projektet som beskrivs i denna rapport handlar om att ta fram en förslagsmodell för att möta personalens behov. Modellens utformning baserades på personalens önskemål för rumsvisning. Modellen skapades utifrån diskussion med sjukvårdspersonal, en observationsstudie samt analys av data från Karolinskas journalsystem, TakeCare. Inspiration till modellen hämtades från en befintlig prototyp på enheten Strategisk Sjukvårdsutveckling och Vårdproduktion, Karolinska Solna. Arbetet utmynnade i en rumsvisningsmodell som skapades i programmet Tableau och integrerades med en rörelsesensor. Modellen kan detektera aktivitet av rörelse i ett rum och presentera denna aktivitet i rumsvisningmodellen i Tableau. Denna modell kan dock inte i nuläget redovisa för vem som befinner i rummet eller om rummet har kvitterats. För att uppfylla dessa kriterier behöver förslagsmodellen utvecklas mer omfattande. Detta är ett potentiellt vidare arbete inom området.
The staff at the children's ward Albatross, Karolinska University Hospital in Huddinge, have identified a need to access information about the number of vacant and occupied rooms in the department in a user-friendly and easily accessible way. Suggestions for a visual digital solution to the department could help create more efficient work. Karolinska University Hospital has currently no solution to forfill this need. The project described in this report is about developing a proposal model to try to forfill the needs of the staff. The model design was based on the staff's wishes for room displaying. The model was created on the basis of discussion with healthcare professionals, an observation study and an analysis of data from Karolinska's journal system, TakeCare. Inspiration for the model was taken from an existing prototype on the Unit Strategic Health Care and Care Production, Karolinska Solna. The work resulted in a space display model created in Tableau Software and integrated with a motion sensor. The model can detect movement activity in a room and present this activity in the Table View model in Tableau. However, this model can not currently display for who is in the room or if the room has been subscribed. In order to meet these criteria, the proposal model needs to be developed more extensively. This is potential further work in the field.

To conserve threatened species it is important to protect the productive individuals, and so I aimed to identify factors accounting for individual-level variation in long-term reproductive success. I examined current breeding characteristics that might explain past reproductive performance amongst experienced breeders.

In the domain of UAVs, endurance and range are key utility factors. However, small-sized UAVs are faced with serious limitations regarding energy storage options. A way to address this challenge is to seek for energy from the surrounding environment. One flight technique, called dynamic soaring, has been perfected by large seabirds like the albatross, which enables them to wander effortlessly in southern oceans. This thesis investigates the feasibility to find inspiration from the biological world in order to address the issue of limited endurance. First of all, an extensive literature background sums-up a range of technical aspects that can be learnt out of the flight of albatrosses. It reviews their morphology, flight performance and sensitivity to wind strength, their flight characteristics and energy expenditure management. Then, a methodology to simulate dynamic soaring flight is built-up by focusing first on adequate models for the vehicle and for the environment. It details the way those models are described quantitatively and qualitatively. As for the vehicle, a point mass model is chosen and applied to fixed-wing gliders of several scales, as well as to an albatross of generic dimensions. The environment is first modelled by classical boundary layer theory on a rather flat surface and then refined by taking into account specificity about the ocean boundary layer, such as varying roughness length and surface waves. Equations of motion are detailed for both points of views, earth-relative and air relative. This yields two different sets of equations of motion, eventually representing equivalent physics. An optimization problem is then set in order to determine, for the vehicle, how to extract energy from its environment. Variations in objective function and in constraints are described before presenting the numerical integration scheme which converts the optimization problem into that of finite-dimension. The solving tools and their specificity are presented, followed by a validation of the overall methodology with a particular study case from the literature. Basic principles of dynamic soaring flight are explicated by using a specific closed-loop study case. Energy-harvesting mechanisms are disclosed locally and next integrated over the whole flight path. A further illustration of dynamic soaring is provided by relaxing some periodicity constraints and opening the trajectory. The specificity of the ocean boundary layer environment is finally implemented and a refined energy-harvesting strategy is presented. Air relative equations of motion are dimensionless so as to highlight specific dynamic soaring behaviours, in the case of a simplified linear wind profile and eventually by finding an appropriate non-dimensionalization for a logarithmic wind profile. Conditions of similarities between dimensionless solutions are described and some basic dynamic soaring characteristics are outlined. Finally, various dynamic soaring performance study case are computed. Optimized trajectories are implemented for the selected vehicles and compared on a required wind strength basis. The sensitivity of the required wind strength to the net flight heading as well as to the ground clearance and to the surface roughness length is determined by drawing performance charts. In order to enlarge the scope of favourable dynamic soaring conditions, thrust-augmented trajectories are considered. The range improvements offered by dynamic soaring are compared to a straight line case, for different wind strength and different net flight headings.

Most albatrosses are critically endangered, endangered or vulnerable due to the deleterious impact of fisheries, pollution, introduced species, habitat alteration, and climate change. Foraging behaviour influences many aspects of seabird biology, and a detailed understanding of foraging ecology is required to better predict the impacts of significant changes to the marine environment. Campbell Albatross (Thalassarche impavida) is a threatened endemic, confined to a small number of locations on Campbell Island, New Zealand and was recently split from the closely related Black-browed Albatross (T. melanophrys). We currently lack much basic information on the foraging behaviour of this species, hindering our ability to understand how change may have occurred in the past and make predictions about it’s long-term future. First, I used GPS loggers and stable isotope analysis of blood to investigate how distribution and foraging effort (distance travelled and duration) varied with sex and breeding stage. I found that Campbell Albatrosses are sexually dimorphic and showed sex-specific foraging behaviour and habitat use – although this varied by stage of reproduction. Because males and females may be vulnerable to different threats, such as interactions with fisheries, I compared the spatial overlap and high resolution spatio-temporal overlaps between fisheries vessels and albatrosses within New Zealand’s Exclusive Economic Zone (EEZ). Albatrosses utilised 32% of the EEZ, however they overlapped with fisheries vessels in only 0.20% of the area. Previous research has demonstrated that the influence of fisheries vessels goes beyond the immediate location of the boat itself. Campbell Albatross have low levels of spatio-temporal overlap with fisheries – with males overlapping more than females. More generally, my results indicate that adding data on fine scale interactions will improve fisheries risk assessments, and provide information needed for the conservation and management of the Campbell Albatross. A key development in recent ecological research has been a greater appreciation that inter-individual variation in foraging behaviour can have profound population-level consequences. Accordingly I tested for individual differences in foraging behaviour in Campbell Albatrosses. The majority of individuals demonstrated both annual and inter-annual individual consistency in foraging locations, and the degree of specialisation was influenced by both sex and year. Consistent terminal latitude and longitude of foraging trips indicated high foraging area fidelity with a degree of flexibility in the fine-scale location. During brooding, females used the Campbell Plateau and showed more consistent behaviours than males, which tended to forage in the Southern Ocean. This adds to a growing body of evidence of individual foraging specialisation among seabirds in general and albatrosses in particular and reveals marked inter-individual differences in vulnerability to threats. In light of the evidence of individual foraging specialisations in the Campbell albatross, I also preformed a literature review of individual foraging specialisations across all seabirds. I found studies examining foraging specialisation for 35 species, with 28 (80%) providing evidence of consistent inter-individual differences (i.e. specialisation). Current studies suggest that specialisation is influenced by environmental variability and resource predictability, however, with limited data in tropical regions, more studies are needed to test these links. In summary, my thesis has provided new information on Campbell Albatross foraging ecology. Sex specific variations in behaviour and habitat use may influence conservation and management strategies. I have been able to contextualise the consistent individual differences in foraging distribution described for this species in light of global patterns of individual foraging specialisation in seabirds and highlight future areas of research.

The aim of this thesis is to examine the relationship between the Royal Australian Air Force (RAAF) and the Royal Australian Navy (RAN) regarding the operation of aircraft from ships of the RAN and from RAAF shore bases. The effects of the separate intellectual development of maritime doctrine in the RAAF and RAN, and the efforts of the two Australian services to transfer theory into practice will be considered in the pre- (and post) World War II period, with due consideration of the experience of the services in both wars. The thesis will also discuss the problems that were faced by the RAAF and RAN to develop mutually acceptable operational procedures to enable the efficient use of aircraft in a maritime setting. The influence and effect on RAAF and RAN doctrine and equipment procurement, as a result of the special relationships that developed between the Air Force and Navy of Australia and Britain will be critically examined. A similar approach to the post war US/Australian relationship, and its effect on the Australian services, will also be critically examined. The thesis being propounded is that the development of a unique Australian maritime policy was retarded due to a combination of the relationship with Britain and the United States, lack of suitable equipment, lack of clear operational concepts in both the RAAF and RAN and the parochial attitude of the most senior commanders of both Services. The study has been based on Department of Navy, Department of Air and Department of Defence documents held in the National Archives of Australia in Canberra and Melbourne. In addition, relevant documents from the Admiralty and Air Ministry related to the development of naval aviation on RAN vessels during World War I, the attitude of the RAF toward the deployment of RAAF units to Singapore, and the negotiations that resulted in the procurement of HMA Ships Sydney and Melbourne, have been perused. Wartime operational records of the RAAF have been examined to obtain data to enable a critical study to be made of the RAAF anti-submarine campaign, torpedo bomber operations and the maritime campaign undertaken from bases in North Western Area during World War II. The influence of the commander of the United States 5th Air Force has also been incorporated in the discussion. The research uncovered procedural and operational variations between the two Services, the diversion of key elements from Australian command and the priority given to the American line of advance that resulted in Australian operations being given a secondary, supportive, status. A conclusion reached as a result of this research has been that the development of a unique Australian maritime aerial capability was restricted by the requirement of Britain to deploy flying units to Singapore in 1940. Similarly, the pressure exerted on the RAN by the Admiralty to purchase the Light Fleet Carriers in the late 1940s was more in the interests of the RN and British foreign policy than that of the RAN. Overall, the relationship with the Britain and the United States masked the real weakness in Australia???s maritime operations and retarded its development.

Dynamic soaring is an engineless flight technique, which extracts energy from a wind gradient. i.e. a change in wind speed with height. It is the key method by which albatrosses achieve their long endurance flight of several thousand miles, flown with hardly a flap of their wings. Such flying takes the albatross close to the water's surface and usually occurs in strong wind conditions. Development of unmanned aerial vehicles (DAVs) is driven by the need of long endurance flight. Techniques such as increasing the engine's fuel efficiency and increasing the amount of fuel carried on-board, suffer from diminishing returns. To achieve ultra long en- durance flight the limits of on-board energy storage must -be overcome by exploiting a source of ambient environmental energy. This thesis investigates dynamic soaring flight as a means of propulsion for DAVs of about 3 metres wingspan. Trajectory optimisation is the central method of investigation used in this thesis. A faster and more efficient approach is presented in this work. by exploiting the DAV's flight model's differential flatness property. The trajectory optimisation process is used to establish outer bounds on the range of feasible wind speeds. for a generic example DAV. From these outer bounds, the probability of favourable winds is investigated, in six candidate locations in the Antarctic Ocean. the Atlantic Ocean, the North Sea and the English Channel. Our example DAV's flight performance closely matches the albatross' flight performance in its natural habitat, the Antarctic Ocean. However, the achievable likelihood of favourable winds is too low in European waters to justify using dynamic soaring as a primary means of propulsion and it must be used together with other flight techniques and propulsion methods to achieve adequate reliability and robustness. By studying the sensitivity of the minimal and maximal wind conditions to flight path con- straints and physical parameters of the DAV model, further insight is gained into the technique of dynamic soaring. Previous work by other authors concentrated upon finding general tra- jectories, with flight models carefully normalised to reduce the number of parameters to one or two variables which represent the whole aircraft. In this thesis, parameters are considered individually. Key results are identification of the maximum airspeed limit as a key factor for the upper bound on feasible wind speeds and the height of the trajectory's low point above ground as a key factor for overall performance. Establishing outer bounds on the feasible wind speed range naturally raises the question of which range of wind speeds within the outer bounds can be exploited in practice. Wind speeds of sufficient magnitude for dynamic soaring are strongly associated with atmospheric turbulence. Because dynamic soaring trajectories are situated very close to the surface, trajectory errors are a particular concern. The ability of an DAV to fly in turbulent conditions is thus closely related to the ability of its control system to reject external disturbances. The performance of a periodic LQR-based controller is evaluated in simulation with particular care having been placed on the turbulence model. It was found, that stabilising the UAV on the nominal trajectory does not necessarily coincide with good energy management and a future control system design should explicitly address energy extraction and management.

Includes bibliographical references.
I studied a long-term data set for Wandering Albatrosses Diomedea exulans collected at sub-Antarctic Marion Island to investigate adult survival, breeding biology and factors affecting reproductive success of this long-lived pelagic seabird. Until recently, the complex adult life cycle has caused biases in conventional mark-recapture modelling analyses that assume that recapture probability is equal for 'observable' and 'unobservable' states of the biennial adult life cycle. During 'sabbaticals' taken after successful and late-failed breeding attempts, the chances of resighting an adult Wandering Albatrosses are reduced, thus affecting estimated recapture rates. I applied a multi-state mark-recapture method to the colony breeding data from Marion Island (1987-2005). This method allows individual albatrosses to move through a network of breeding states according to previous breeding history using transition probabilities to estimate survival, breeding and breeding success probability. The best fit models in the multi-state analysis were those representing constant survival and independent breeding probabilities, suggesting that Wandering Albatrosses constrain reproductive investment to ensure long-term survival. I used the parameter estimates in a transition matrix to calculate the steady state equilibrium for the Wandering Albatross breeding population. For the first time I was able to estimate that approximately 3000 pairs of Wandering Albatrosses use Marion Island for nesting. I also describe the effects of age, sex and experience on Wandering Albatross reproductive success. Birds that were most successful began breeding at the mean age of first breeding and older and younger birds were less successful in 5/10 year periods after the onset of breeding. Disappearance from the population decreased with an increase of age of first breeding. I tested the selection and experience hypotheses on birds with 'complete' histories defined according to an imposed rule on recovery data. Males appeared to increase breeding success as a result of selective removal of low-quality individuals from the population (the selection hypothesis), whereas females appeared to improve their breeding success as a result of increased experience.

The Galápagos Archipelago is recognized internationally as a unique eco-region, and many of the species that inhabit these islands can be found nowhere else on Earth. The Ecuadorian government recognized the value of this ecosystem, and, beginning in 1959, they designated 97% of the Archipelago as Ecuador's first National Park. The Charles Darwin Foundation also was founded in 1959 and, since then, the Park Service and the Foundation have worked towards preserving the Galápagos' unique flora and fauna for future generations. The waved albatross (Phoebastria irrorata) is the largest bird species found in the Galápagos Archipelago and was recognized as an iconic species early in the Park's history; it is the only tropical albatross. This species spends the majority of its life foraging at sea and is an important predator in the Humboldt Current off of the coast of South America. With the exception of a few pairs, this albatross breeds entirely on the southeastern most island of the archipelago, Española. Tourists visit Española every year to watch the elaborate courtship dances of this species, and albatrosses in general have been the foci of legends among sailors for centuries.

M.P. Harris (1969) began banding waved albatross as early as 1961, marking the beginning of a long-term monitoring program with a focus on estimating age-specific first-time breeding, abundance, and survival. This initial effort resulted in the first estimates of abundance and survival for the waved albatross (Harris 1973). Following these initial estimates, the population size of the waved albatross has been estimated in 1994 (Douglas 1998), 2001 (Anderson et al. 2002), and 2007 (Anderson et al. 2008). These estimates suggest that the population has been declining since 1994. Motivated by this apparent decline, Awkerman et al. (2006) investigated survival and concluded that survival estimates from 1999-2005 were lower than average survival from 1961-1970 (Harris 1973). Today, the waved albatross is considered critically endangered, with bycatch in artisanal longline fisheries and the increased occurrence of El Niño-Southern Oscillation events thought to be contributing to these observed declines in survival and abundance. Given these observed declines in the waved albatross, the importance of the species in the ecosystem, and its intrinsic value in terms of biodiversity, continued monitoring and analysis efforts are needed to evaluate trends over time, and to gauge the effectiveness of management actions. My thesis is focused on these topics.

In Chapter 1:, I describe a framework to estimate abundance of wildlife populations, apply this framework to estimate population size of the waved albatross at a major breeding colony on Española Island, and I conclude by providing recommendations for future island-wide surveys of this species.

In Chapter 2:, I revisit the dataset collected by M.P. Harris and the Galápagos National Park from 1961-1981 as well as a more recent dataset collected by K.P. Huyvaert and colleagues. I analyzed these datasets in a multistate mark-recapture framework to estimate and compare estimates of adult survival as well as other important demographic parameters that have not yet been evaluated for this species.

Bycatch from fisheries and extreme weather events have influenced survival and breeding probabilities of many pelagic seabird species worldwide. Lower adult survival of the waved albatross is thought to be associated with bycatch in the small-scale fishery located off of the coasts of Peru and Ecuador as well as with El Niño-Southern Oscillation events. Previous efforts to document these threats have not formally considered that a variable proportion of the population does not breed every year or that different life history stages may have different survival rates.

The results from Chapter 1 suggest a continued decline in the principal breeding population of the waved albatross since 1994, and Chapter 2 shows indirect evidence that this decline may be linked to higher mortality associated with recent documented increases in small-scale longline fishing effort off of the coast of South America. Outside of the Galapagos Marine Reserve where fishing is heavily regulated by the Galapagos National Park Service, little is done to directly manage artisanal fishing operations off of the coasts of Peru and Ecuador. Conservation initiatives recognizing the environmental impact of fishing in this zone have been promoting reduction of seabird bycatch by educating local fishermen. Despite these conservation efforts, the results from my thesis suggest a continued population decline for this critically endangered species and additional mitigation may be needed for the persistence of the waved albatross.

Denna fallstudie avser att titta på kritiska faktorer i projektimplementering. Projektimplementering avser hela genomförandet av projekt efter att avtal har tecknats till avslut, då kunden och leverantören har uppfyllt sina respektive åtaganden. Kritiska faktorer är kommunikation, ledningens stöd, planering, personal, teknik, kundens acceptans, kundkonsultation, samordning och problemlösning. Punkterna är sammanfattade i Schultz, Selvin och Pintos Projekt Implementerings Profilen (PIP). Projekt kännetecknas av att de, med dedikerade resurser under en begränsad tid, skall nå projektetmålet, vilket kan vara en nog så stor utmaning. Studien utgår från intervjuer med projektkonsulter från IT-bolaget EKAN Albatross AS. Syftet är att fånga hur de upplever kritiska faktorer i projektimplementering. Totalt har 8 stycken intervjuer genomförts med 5 respondenter involverade. De arbetar som projektkonsulter på Albatross kontor i Oslo och Stockholm. Två olika intervjumetoder har används, den första mer allmänt orienterade för att fånga hur konsulterna ser på sin projektverksamhet. Den andra intervju metoden är mer strukturerad frågor ställda utifrån PIP-faktorerna. Konsulterna arbetar med att utveckla och implementera affärsdatasystem till kund. Projekt implementerings profilen fångar väl konsulternas upplevelser, men tar inte upp den politiska dimensionen som kan förekomma i genomförandet av projekt.

Thesis: Ph. D. in Mechanical and Ocean Engineering, Massachusetts Institute of Technology, Department of Mechanical Engineering, 2018.
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 164-172).
Albatrosses extract their propulsive energy from horizontal winds in a maneuver called dynamic soaring, and travel impressive distance (5000 km/week) by "riding the winds". Accordingly, for albatrosses flight is barely more strenuous than rest. While thermal soaring, exploited by birds of prey and sports gliders, consists of simply remaining in updrafts, extracting energy from horizontal winds necessitates redistributing momentum across the wind shear layer, by means of an intricate and dynamic flight manoeuver. Historically, dynamic soaring has been described as a sequence of half-turns connecting upwind climbs and downwind dives through the surface shear layer. Relaxing the half-turn hypothesis, this thesis numerically and analytically studies the "minimum-wind" problem i. e. the question of how much wind is required to stay aloft with dynamic soaring, and what is the optimal flight strategy to do so. Contrary to current thinking, but consistent with GPS recordings of albatrosses, it is shown that when the shear layer is thin the optimal trajectory is composed of small-angle, large-radius arcs. Essentially, the albatross is a flying sailboat, sequentially acting as sail and keel, and most efficient when remaining crosswind at all times. The thin-shear analysis is then extended asymptotically, predicting in closed-form the most efficient dynamic soaring trajectory in wind shears of finite thickness. Building upon the conceptual study of dynamic soaring, a robotic system inspired by the albatross is proposed: the "flying sailboat", i. e. a low-flying, water-skimming airplane powered by a keel-and-sail combination. Potentially, the flying sailboat could travel 10x faster than a traditional sailboat of the same size, survive in much rougher seas than hydrofoil boats, and carry 10x more payload than a naive robotic copy of the albatross. A mechanical prototype is presented, with the keel and height controlled with feedback-linearization controllers. Experimental results demonstrating the critical aspects of the system's operation and control are reported: stable extreme-low height flight concurrent with controlled keel immersion and force generation.
by Gabriel D. Bousquet.
Ph. D. in Mechanical and Ocean Engineering

Le Dynamic Soaring est une technique de vol qui extrait l'énergie du vent par des manoeuvres particulières. Il estdirectement inspiré par le vol des albatros, qui parviennent à se maintenir en vol sans battre des ailes sur des centaines dekilomètres. Les types de manoeuvres nécessaires ainsi que les dimensions de l'oiseau suggèrent un potentiel de transposerle Dynamic Soaring aux véhicules de faibles dimensions. Cette thèse étudie la faisabilité d'exploiter le Dynamic Soaring dansle but de longue endurance vol autonome. Modèles et simulations sont menées afin de dériver une trajectoire quimaintienne le véhicule en vol sans apport d'énergie interne et d'étudier la physique de ce vol particulier,. Ensuite, larecherche se concentre sur l'influence des variables d'environnement et du cap de vol sur les sur les performances parDynamic Soaring
Dynamic Soaring is a flight technique which extracts energy from the wind through particular maneuvers. It is directlyinspired by the flight of Albatrosses, which manage to sustain non-flapping flight for hundred of miles. The types ofrequired maneuvers as well as dimensions of the bird suggest a potential to transpose Dynamic Soaring to small dimensionvehicles. This PhD investigates the feasibility to extract energy by Dynamic Soaring in the purpose of long enduranceautonomous flight. Models and simulation are conducted in order to investigate the physics of this particular flight as wellas the feasibility to derive a trajectory which keep the vehicle aloft without internal energy contribution. Then the researchfocuses on the influence of environment variables and of travel heading on Dynamic Soaring performances

Since the advent of the Internet expeditioners travelling alone or in small groups to remote locations have been using email and websites to communicate with sponsors, supporters, friends and family. This brings new communication opportunities to expeditioners and at the same time may be changing the expedition experience. The author used the experience of participating in an 11-month sailing voyage around the world as a platform for this research by project. The purpose of the voyage was to raise awareness of the plight of the albatross. The author examined how the Internet shaped this expedition, the purpose of expedition communication and how meaning was constructed for a remote audience. Using a constructionist epistemology, a phenomenological approach is used in the development and analysis of a narrative account of the voyage, its preparation and aftermath. The Exegesis contains a detailed account of one Leg of the Voyage, from Cape Town to Melbourne, with a particular focus on the online communications. A full account of the voyage, again with a particular emphasis on communications, is contained in the Durable Record. The potential availability of Internet communication was found to have been intrinsic to the design of the expedition and enabled the Voyage to forgo traditional media sponsorship and yet still attract and engage a worldwide audience through an institutional community website. The lack of use of the Internet's capability to support online discussion and build communities on this Voyage and other expedition websites sampled, is explored and it is proposed to be an expression of these expeditioners' possible disinterest in feedback. The building of online communities around an expedition website is suggested to be an area of opportunity with the potential to engage site visitors, to enable new insights to be gained into the life of expeditioners, and to provide greater exposure for sponsors. A simple classification of expeditions by their leadership, organisation, purpose and membership is proposed and the differing purposes of communication in each considered. The use of email on the voyage was found to facilitate and improve contact with supporters, family and friends. Whilst adding a sense of security it was also found to be time consuming, stressful, power hungry and to build a sense of obligation to communicate. Its general reliability led to exchanges on non-critical matters and to a reduction in the feeling of remoteness that some expeditioners may be seeking. Whilst on this voyage technical and budgetary constraints limited the full use of the Internet's capability to utilise text, images and sound to construct meaning, the effective and timely use of a short daily narrative, aimed at a known audience is demonstrated. The author justifies drawing learning from his participation in the Voyage through the use of experiential learning and reflective learning theory arguing that the preparation for expeditions, participation in them and mediated reflection following them, are rich learning environments provided that good records are kept, particularly a frequently written personal journal.

Date June 04, 2008

Level Master Thesis EFO705, 10 points (15 credits)

Authors Pornratchanee Sethakaset Tanawan Santimataneedol

Bangkok, Thailand Bangkok Thailand

Date of Birth: 28 October 1982 Date of Birth: 5 March 1984

Title The Application of Human Resource Management in Thai SMEs –

A Case Study of Albatross Company Limited

Supervisor Mona Andersson

Problems : How can the entrepreneur of SMEs manage their human resources?

Can previous research and studies about HRM in SMEs be applied in the Thai entrepreneurial SME?

Does the HRM in the company change and transform over time?

Purposes : The purposes of this study are to review the relevant studies and research about HRM in SMEs in order to investigate how human resources are managed in SMEs and to determine if the previous studies are applicable to Thai entrepreneurial SMEs.

Methodology : This master’s thesis is based on a qualitative approach in order to investigate HRM in SMEs and easier to understand the behavior in a certain case. The main secondary data is also collected from website which is the utilizing material for this thesis.

Conclusion : In this study, it was concluded that this Thai SME manages its human resource in a mixture between informal and formal way. HRM is used and practiced more as the company grows which the entrepreneur plays a central role in the Human Resource Management in SMEs.

A fundamental condition of the struggle for existence is resource limitation. Optimal foraging theory describes how individuals refine behavior to most efficiently exploit available resources. For colonial breeding animals, such as seabirds, competition for limited resources is amplified by a high density of competitors at feeding grounds near the colony, which can lead to a diversification of foraging strategies that best exploit available resources. Laysan and black-footed albatrosses (Phoebatria immutabilis and P. nigripes, respectively) breed sympatrically and synchronously in dense colonies on small atolls throughout the northwestern Hawaiian Islands. While the distributions and habitat preferences of these congeners are well described, the variability in foraging strategies driven by niche partitioning is not. In chapter 1, I used fine-scale behavioral data from GPS data-loggers to tease apart subtle behavioral nice partitioning between and within Laysan and black-footed albatrosses constrained to poor-nutrient tropical waters during the most energetically-demanding reproductive stage in birds: the brood-guard. Albatrosses showed discrete behavioral partitioning both between and within species, which was driven by differences in nocturnal and diurnal foraging and by sex-specific strategies. Black-footed albatrosses exhibited greater variability in foraging patterns suggesting they may experience strong intraspecific competition at Tern Island. In chapter 2, I employed a novel adaptation of a biochemical diet analysis, quantitative fatty acid analyses, to investigate dietary niche partitioning across the breeding season. This analysis characterized diet of individual adult albatrosses across the breeding season, from incubation to the chick-brood, for the first time in these species. Additionally, this research extended beyond diet characterization to quantify dietary dependence on fisheries-associated resources for these two species. One of the primary threats to albatross is the incidental mortality of birds from fisheries bycatch, therefore, understanding the incidence of fisheries-associated food in the diet of a breeding colony of albatrosses could have important conservation implications. While older birds tended to consume more squid than younger birds, we did not identify an age bias in birds that exploited fisheries resources. Parallel with results from the behavioral analysis in chapter 1, I found that black-footed albatrosses had greater dietary flexibility than Laysan albatrosses at a population level, and a greater degree of dietary specialization at the individual level. In the final chapter, I looked at how the obligatory act of flight feather molt impacted activity levels and space use across the post-breed migrations, when albatrosses are freed from central place foraging constraints, but limited by demands of self-maintenance. I found that activity levels, but not habitat use, were impacted by molt extent. Habitat use appeared to be primarily driven by consistent individual preferences, with birds showing a high degree of site fidelity to their post-breeding molting grounds. A clear decrease in home range size with age indicated that birds spend less time searching for profitable feeding grounds when they are older, likely a product of accumulated memory and experience in these long-lived species.

Black-footed albatross (Phoebastria nigripes) are among the many species of seabirds whose numbers are affected every year by anthropogenic impacts. Until now, no one has looked at the transfer of contaminants via soil to P. nigripes. However, studies have been done on how the Laysan albatross (P. immutabilis) is affected by lead in the soil (Work and Smith, 1996; Finkelstein et aI., 2003). Studies on endocrine disruption and effects of PCB contamination in wildlife have shown that estradiol and testosterone levels may be ahered and skewed as a result of anthropogenic sources (Fry and Toone, 1981; Grasman et aI., 1996; Auman et aI., 1997). Thus, the levels of gonadal steroids may function as indicators of exposure to polycWorinated biphenyls in the soil affecting these long-lived seabirds. The objective of this study was to determine if nesting in PCB-contaminated areas affects hormone balance due to endocrine disruption in both adult and chick black-footed albatross on Midway Atoll National Wildlife Refuge (NWR) and black-footed albatross chicks on Tern Island, Hawaiian Islands National Wildlife Refuge (HINWR). This thesis is divided into four parts. Chapter 1 contains the literature review and information on research background. The results for each island are presented in following chapters with the methods section similar at both locations. Chapter 2 compares hormone variation and soil contamination in two nesting sites on Midway Atoll. Chapter 3 discusses hormone variation between two nesting sites on Tern Island. Chapter 4 summarizes the work done in this study and suggests research that might be done in the future.
viii, 73 leaves

This thesis presents the results of an archaeological investigation of shell matrix sites, and in particular, shell mounds sites that occur around the shores of Albatross Bay, near Weipa on the north western Cape York Peninsula, northern Australia. It is the contention of this thesis that earlier approaches to the investigation of shell mound sites in northern Australia have tended to place too much emphasis on developing long-term explanatory models that gloss over explanations for the specific roles of these unique sites in past economic systems. While long-term explanations represent important contributions, it is argued here that short-term decadal scale modelling of the production systems associated with shell mound formation and use are required in order to fully understand the significance of the mid- to late Holocene emergence of these types of sites. A focus on production – defined in a substantive economic sense – is a suitable avenue through which archaeologists can expand our understanding of the role of these features in past gatherer-hunter societies, and their broader importance on longer-term time scales The thesis thus develops a detailed model of the production strategies associated with the formation of shell mound sites that occur around Albatross Bay, while also considering the broader significance of this model, particularly within the context of Cape York Peninsula. It presents the results of field surveys and excavations carried out around Albatross Bay by the author, as well as a detailed review and analysis of work carried out by others. It is argued that shell mounds are the result of relatively specialised production activities focussing on a very specific resource base: mudflat shellfish species. Shell mounds offered a range of unique benefits for people engaged in these specialised activities, including as camp sites and as specialised activity areas. These events were inherently flexible in size and in terms of timing, reflecting the dynamic nature of the resource base itself; yet the flexible nature of this production strategy also enabled more regular small scale social gatherings, along with a range of social and economic benefits to participants, than would have been otherwise possible. It is proposed that these types of strategies may represent an important characteristic of the production systems employed by gatherer-hunter peoples in late Holocene Cape York. Overall, this thesis makes a significant contribution to both our understanding of late Holocene lifeways at Albatross Bay as well as to our understanding of the broader significance of the emergence of shell mound sites in Cape York. Furthermore, it highlights the range of insights that can come from a focus on short-term modelling of gatherer-hunter lifeways alongside approaches oriented toward longer-term explanations of economic, social and environmental change.

Albatross populations are currently in decline around the world. Survival and reproduction of these large pelagic birds depends mostly on the conditions they encounter in their marine environment. Their ability to range far across ocean basins exposes them to a variety of anthropogenic threats. It is thus crucial to understand spatial and temporal patterns in the distribution and habitat use of each albatross species during different stages of their annual cycle in the context of seasonally changing demands as well as environmental constraints, in order to develop effective conservation measures. Using Global Location Sensing (GLS) loggers I investigated the non-breeding movements and habitat associations of three threatened or near-threatened albatross species breeding in New Zealand’s Chatham Islands, the Chatham Albatross (Thalassarche eremita), Northern Buller’s Albatross (T. bulleri platei) and Northern Royal Albatross (Diomedea epomophora sanfordi), within South American waters. Chatham and Northern Buller’s Albatrosses mainly occupied waters with mean sea surface temperatures (SST) of 17-18ºC along the coasts of Chile and Peru, while Northern Royal Albatrosses were mostly found in 10-12ºC waters off southern Chile and Argentina. Monthly movement patterns were linked to seasonal shifts in temperature range, suggesting SST was an important environmental factor in explaining the observed spatial and temporal patterns. GLS loggers were also applied to study the patterns of movement and habitat use of Chatham Albatrosses when migrating across the South Pacific between breeding and non-breeding grounds. The route and timing of migration were consistent over the three year period of the study, although subject to individual variation. Stopovers on migration were found to be common, lasting between 3 and 26 days. Activity patterns suggested that birds stopped in order to forage en route. Lastly, I used high resolution Global Positioning Sensing (GPS) loggers to address the fine-scale movements and habitat selection of foraging Chatham Albatrosses over three years during early chick rearing. This is a time when their behaviour is expected to respond to increased energetic demands as they are feeding young chicks. Foraging trips lasted between 1 and 6 days and the foraging range rarely exceeded 400 km. The location of potential foraging spots varied between years, but followed non-random patterns in bathymetry, slope, SST and Chlorophyll a. The results presented here suggest that albatrosses rely on predictable habitat features but are flexible to respond to fine scale changes within their marine environment. The dynamic nature of both birds and environment may prove challenging but has to be taken into account in conservation planning.

An understanding of the spatio-temporal dynamics of marine predator populations is essential for the sustainable management of marine resources. Tagging studies are providing ever more information about the movements and migrations of marine predators and much has been learned about where these predators spend their time. However little is known about their underlying motivations, making it difficult to make predictions about how apex predators will respond to changing environments. While much progress has been made in behavioural ecology through the use of optimality models, in the marine environment the necessary costs and benefits are difficult to quantify making this approach less successful than with terrestrial studies. One aspect of foraging behaviour that has proved tractable however is the optimisation of random searches. Work by statistical physicists has shown that a specialised movement, known as Lévy flight, can optimise the rate of new prey patch encounters when new prey patches are beyond sensory range. The resulting Lévy flight foraging (LFF) hypothesis makes testable predictions about marine predator search behaviour that can be addressed with the theoretical and empirical studies that form the basis of this thesis. Results presented here resolve the controversy surrounding the hypothesis, demonstrating the optimality of Lévy searches under a broader set of conditions than previously considered, including whether observed Lévy patterns are innate or emergent. Empirical studies provide robust evidence for the prevalence of Lévy search patterns in the movements of diverse marine pelagic predators such as sharks, tunas and billfish as well as in the foraging patterns of albatrosses, overturning a previous study. Predictions from the LFF hypothesis concerning fast moving prey are confirmed leading to simulation studies of ambush predator’s activity patterns. Movement analysis is then applied to the assessment of by-catch mitigation efforts involving VMS data from long-liners and simulated sharks.

Among the species of Diomedea albatrosses, diverse foraging strategies during breeding have been described, indicating species differences in foraging ecology and behaviour. Foraging strategies of Southern Royal Albatrosses, Diomedea epomophora (SRA) breeding on Campbell Island were studied in January – early February 1999 during the latter half of incubation. Movements and activity of ten birds were monitored using satellite transmitters and wet-dry activity recorders. Three birds from a pilot tracking study in February 1997 were also included in some analyses. Foraging strategies, zones used, factors influencing the duration of foraging trips, and the influence of wind conditions were investigated. Foraging activity took place at sites with bathymetric characteristics associated with high productivity: outer shelf and shelf-break zones, with a concentration of activity on a shelf contour south of the Snares Islands. This is in contrast to Wandering (D. exulans) and Gibson’s (D. gibsoni) albatrosses, typically deep oceanic foragers, but is similar to Northern Royal Albatross (D. sanfordi). The maximum distance of foraging trips from the colony was 1250 kilometres (mean 584 +351(SD)). This was closer than for incubating Wandering and Gibson’s Albatrosses but more distant than for Northern Royal Albatross from the Otago Peninsula. The mean duration of 77 foraging trips from 52 nests was 10.11 days for females and 8.76 for males (ns). Foraging trips became shorter as incubation progressed. Foraging trips were shorter, but not significantly so, when the median wind speed throughout the foraging trip was higher. No significant relationship was found between bird mass and duration of foraging trips. The mean cumulative distance flown by the ten birds tracked in 1999 was 4262 km + 1318 (SD). Eight of the ten SRA employed a ‘commute, forage, commute’ foraging strategy, and the other two alternated short bouts of commuting and foraging. Commuting phases were characterised by rapid directional flight with a straight-line distance (range) of 180 km to 800 km between positions 24 hours apart. Foraging phases were characterised by a range of less than 180 km per 24 hour interval and frequent tight turns. Displacement rate between successive uplinks was significantly higher during commuting phases (28.6 kph + 1.93 SE) than foraging phases (15.1 kph + 1.4 SE). Wind strength and direction influenced the timing of the return commute to the colony. SRA covered greater distances at more favourable wind angles relative to flight track (broad reach and close reach) than in head, tail or direct side winds. Birds of low mass (< 8kg) made fewer landings in winds above 40 kph than in lighter winds, whereas heavier birds had a similar level of landing activity across all wind speed bands. One bird was delayed for several days by light winds, and another flew off course during strong winds. Two birds exploited the same window of wind conditions to return to the colony, each flying a similar course in both timing and route. These results define the foraging strategies of SRA during incubation, and demonstrate the influence of wind conditions and other factors on the overall duration of foraging trips and on the timing of commuting and foraging phases.

Jusqu’à aujourd’hui, les traits démographiques du début de vie ont été peu étudiés relativement aux traits adultes chez une grande majorité d’espèces animales. Les jeunes individus sont généralement plus difficiles à étudier en milieu naturel du fait de leur taille plus petite, de leur comportement plus mobile et des forts taux de mortalité qu’ils subissent. Cependant, la bonne compréhension des processus démographiques requiert la prise en compte de l’ensemble des stades de vie. Le manque de connaissance concernant les plus jeunes individus est particulièrement préjudiciable pour les espèces longévives. En effet chez ces espèces, les individus immatures représentent une partie importante de la valeur reproductive totale et ont ainsi une forte influence sur l’ensemble de la dynamique de la population. Ainsi, ces lacunes affectent notre capacité à effectuer des projections démographiques réalistes dans un contexte de changements globaux et plus généralement limitent notre compréhension de l’évolution des traits d’histoire de vie. Afin de pallier à ce manque, cette thèse porte sur l’étude des traits d’histoire de vie en début de vie chez une espèce d’oiseau marin : l’albatros hurleur Diomedea exulans. Chez cette espèce particulièrement longévive, la période d’immaturité peut durer une dizaine d’années. En se basant sur un suivi individuel à long terme et des analyses de type capture-marquage-recapture, nous avons estimé la survie en début de vie ainsi que l’accès à la première reproduction en fonction de l’âge et du sexe. Nous avons également étudié les effets potentiels de facteurs extrinsèques (climat, pêcherie) et intrinsèques (densité dépendance, âge parental) sur ces paramètres. De nombreuses relations entre les taux vitaux de ces jeunes individus et leur environnement ont été décrites. Sur un plan plus théorique, nous avons également pu tester différentes prédictions comme la canalisation des traits d’histoire de vie ou l’existence de différentes stratégies d’histoire de vie au sein d’une même population. Au cours de ce travail, une attention particulière a été portée aux variations des traits démographiques à l’échelle individuelle. Notre étude montre que les taux vitaux d’individus de même âge et de même sexe peuvent être très variables. Nous avons pu associer les traits démographiques en début de vie aux performances futures au stade adulte et révéler certaines causes de ces variations interindividuelles
To date, early life demographic traits have been poorly studied compare to adult traits in the vast majority of animal species. Young individuals are usually more difficult to study due to their small size, their mobile behavior and the high mortality rate that characterizes their life stage. However, the full understanding of the demographic processes requires the integration of all life stages. This lack of knowledge toward early-life stages is particularly detrimental for long lived species. Indeed for these species, the immature component represents a substantial part of the total reproductive value, having a high influence on the whole population dynamics. Hence, such limitations affect the accuracy of population projections in the context of global change and more generally our understanding of life history trait evolution. In order to fill in this gap, this PhD project focuses on early life demographic traits in a seabird species : the wandering albatross Diomedea exulans. In this very long-lived species, the immature period lasts around 10 years. Based on long-term individual monitoring and capture-recapture analyses, we estimated early-life survival and the access to reproduction according to age and sex. We also investigates the respective effects of extrinsic (e.g. climate, fisheries) and intrinsic factors (e.g. density dependence, parental effects) on these parameters. Many relationships between early-life vital rates and environmental variables have been described. From a theoretical perspective, we tested several predictions such as the canalization of life-history traits and the existence of different life-history strategies within a population. In this work, special attention was paid to demographic variations at the individual scale. Our study showed that vital rates of individuals of the same age and sex could be very different. We have linked early-life demographic traits with subsequent adult performances and identified some causes of these individual variations

Age-related variation in demographic rates has significant consequences for population and evolutionary dynamics, and understanding the processes driving such variation is therefore an important aspect of evolutionary ecology. Reproductive performance may vary over the lifetime of an individual, and this may be the result of both variations in reproductive effort and changes in individual competency. For example, increasing experience is likely to have beneficial effects on reproduction during early life, and senescence, or declines in physiological function, may have negative impacts on the performance of older individuals. The rate at which these changes occur can vary dramatically between species, and even between individuals of the same species. However, understanding the causes and consequences of this variation in the rate of ageing is not always straightforward. As well as the individual-level processes described, the phenotypic composition of successive age classes will contribute to age-related variation observed at the population level. Abrupt changes in performance, such as the poor performance of first time breeders, may be obscured if individuals vary in their age at first reproduction. Population-level patterns may also be influenced by selection; for example, the selective disappearance of low quality individuals from older age classes may mask senescent declines in the performance of longer-lived individuals. Moreover, the physiological mechanisms that underpin within-individual changes in performance are not well understood. Unravelling the drivers of such age-related variation requires longitudinal data, following individuals throughout their lives, which presents challenges for the study of natural populations. Albatrosses are among the longest lived vertebrates. In this thesis, I use data from three species of albatross breeding at Bird Island, South Georgia (54°00’S, 38°03’W) to explore age-related variation. Focusing primarily on the wandering albatross, Diomedea exulans, I characterise the relationship between age and various reproductive traits, and decompose the population-level patterns to reveal effects of experience, senescence and terminal effects across the reproductive lifespan of individuals. I then consider foraging behaviour as a proximate driver of changes in reproductive performance in this species. Using tracking data collected over a 20 year period, I find limited evidence for age-related variation in foraging trips taken throughout the breeding cycle. Going one step further, I explore telomere dynamics in the wandering albatross, examining the potential for telomere length to act as a physiological marker of individual state. Finally, I move on to a species comparison, incorporating data from the black-browed (Thalassarche melanophris) and grey-headed albatross (Thalassarche chrysostoma). I compare the population- and individual-level ageing patterns of these three closely related species, and consider these in light of their differing life history strategies.

L’impact écologique et évolutif de la dispersion et de la consanguinité peut être exacerbé chez les espèces insulaires. Les albatros, en particulier, ont un mode de vie exceptionnel qui soulève plusieurs questions à cet égard. Dans cette thèse j’aborde certaines de ces questions. En introduction (chapitre 1), j’énonce des hypothèses spécifiques à l’espèce d’étude, l’Albatros hurleur (Diomedea exulans), en lien avec la dispersion, la dynamique des populations, et la génétique. Cependant, la découverte fortuite d’une diversité génétique très pauvre chez cette espèce a nécessité une redéfinition majeure des objectifs et hypothèses initiaux de la thèse. Donc, les patrons de diversité génétique chez deux espèces « sœurs », les Albatros hurleurs et d’Amsterdam (D. amsterdamensis), sont d’abord étudiés au chapitre 2. Des simulations supportent l’hypothèse voulant que ces deux espèces aient hérité leur faible diversité de leur ancêtre commun qui vivait il y a quelque 0,8 million d’années. Par conséquent, les albatros semblent défier l’opinion répandue voulant qu’une faible diversité génétique réduit nécessairement la viabilité d’une espèce. L’objectif du chapitre 3 était d’identifier explicitement le modèle de dynamique populationnelle correspondant le mieux à la réalité des Albatros hurleurs. Les populations de l’ensemble de l’aire de répartition s’avèrent très peu différenciées au plan génétique. Tous les génotypes forment un seul groupe homogène selon une analyse de groupement, suggérant que les colonies actuelles pourraient descendre d’une même population ancestrale qui avait une faible diversité génétique. À l’opposé, les données de relecture de bagues indiquent qu’environ un oiseau par cohorte a émigré de son île natale au cours des dernières décennies. De ce fait, les données génétiques ne reflètent pas les faibles taux de dispersion contemporains, vraisemblablement parce que les populations n’ont pas atteint l’équilibre migration–dérive. Un modèle de dynamique de métapopulation impliquant la colonisation récente de plusieurs îles semble compatible avec les bas niveaux de diversité et de structure génétiques, bien que d’autres facteurs ont sans doute contribué au façonnement du patron génétique. La diversité et la structure génétiques limitées soulèvent des questions à propos de la consanguinité et de ses effets. Dans le chapitre 4, les données probantes relatives à la consanguinité chez l’Albatros hurleur sont passées en revue. L’hypothèse que le succès reproducteur décroît avec l’accroissement de la similarité génétique des partenaires a aussi été testée en utilisant des données moléculaires et sur l’histoire reproductive des couples. Bien que l’analyse ne supporte pas cette hypothèse, on ne peut exclure la possibilité que ce résultat découle du manque de résolution des marqueurs étant donné la très faible diversité génétique des albatros. Quelques perspectives sur des aspects reliés à la consanguinité (p. ex. son évitement, la purge génétique), basées sur la littérature récente, sont également proposées. En somme, l’étude du cas « albatros » mène à plusieurs hypothèses stimulantes et démontre la complexité de mettre au jour la dynamique de la consanguinité chez les espèces longévives. Dans le chapitre 5, à défaut de pouvoir faire des analyses d’assignation populationnelle (en raison du manque de résolution génétique), le jeu de données sur les albatros, ainsi qu’un second jeu sur le Saumon Atlantique (Salmo salar), ont servi à explorer le comportement d’une méthode d’assignation appliquée de façon routinière en biologie. Les résultats démontrent que des aspects importants (estimation du taux d’erreur, détection de migrants) sont liés à la conformité des données empiriques aux prémisses des tests. Ils soulignent aussi l’importance de valider la procédure d’assignation à l’aide de simulations préliminaires. Cette contribution méthologique se veut en quelque sorte une réponse au manque d’uniformité dans l’application de ces méthodes. Pour conclure, je passe en revue l’ensemble des connaissances sur la dispersion des Albatros hurleurs et je propose une perspective sur les causes de la dispersion et de son évolution chez ces oiseaux. Cette thèse apporte un éclairage nouveau sur la signification et l’impact du monomorphisme génétique dans les populations naturelles, sur la dispersion et la dynamique populationnelle chez une espèce longévive, et propose une vision sur l’interaction entre ces facteurs et l’histoire de vie.
The ecological and evolutionary impact of dispersal and inbreeding may be exacerbated in insular species. Albatrosses, in particular, have an extreme way of life raising several questions in that regard. In this thesis, I address some of these questions. In the introduction (chapter 1), I enounce hypotheses that are specific to the study species, the wandering albatross (Diomedea exulans), in relation to dispersal, population dynamics, and genetics. However, the fortuitous discovery of a very poor genetic diversity in this species led to substantial modifications of the initial objectives and hypotheses of the thesis. Thus, the patterns of genetic diversity in two sister species, the wandering and Amsterdam (D. amsterdamensis) albatrosses, are studied in chapter 2. Simulations support the hypothesis that the two species inherited a poor genetic diversity from their common ancestor, some 0.8 million years ago. Albatrosses thus appear to challenge the widespread view about the negative consequences of genetic depletion on species survival. In chapter 3, the objective was to identify explicitly which model of population dynamics best applies to the wandering albatross. Populations exhibited little genetic differentiation across the species’ range. All genotypes grouped together in a cluster analysis, suggesting that current colonies have derived from one ancestral source that had a low genetic diversity. In contrast, band re-sighting data indicated that about one bird per cohort has dispersed among islands in the past decades. Therefore, low contemporary dispersal rates are not mirrored by genetic data, presumably because populations are not at migration–drift equilibrium. A metapopulation dynamics model involving the recent colonization of several islands seems consistent with the very low levels of both genetic diversity and structure within the wandering albatross. Yet, other factors likely contributed to shape current genetic patterns. The limited genetic diversity and structure raise questions about inbreeding and its effect. Thus, in chapter 4, evidence for inbreeding in the wandering albatross is reviewed. The hypothesis that reproductive success decreases with increasing genetic similarity between mates was also tested using molecular data and pair breeding histories. While the hypothesis was not supported, a lack of resolution from the markers cannot be ruled out given the very poor genetic diversity in albatrosses. Some perspectives about inbreeding-related aspects (e.g. inbreeding avoidance, purging) based on recent literature are also proposed. Overall, this wandering albatross case study leads to several stimulating hypotheses and shows how complex the understanding of inbreeding dynamics in a long-lived species may be. In chapter 5, failing to successfully apply population assignment methods (because of the lack of genetic resolution), data on Atlantic salmon (Salmo salar) were used in addition to the albatross dataset to explore the performance of an assignment method routinely used in biological investigations. Results show that critical aspects (error rate estimation, migrant detection) relate to how test assumptions are met by empirical data. They also stress the need to validate the assignment procedure with preliminary simulations. This methodological contribution is to some extent a response to the absence of uniformity in the way these methods are generally applied. To conclude, using empirical evidence on dispersal in wandering albatrosses, I suggest perspectives on the causes and the evolution of dispersal in these birds. This dissertation provides new insights about the significance and implications of genetic monomorphim in natural populations, about dispersal and population dynamics in a longlived seabird, and proposes a vision about the interaction between these factors and life history.

Le développement post-natal est une étape cruciale pour le reste de la vie d’un individu car c’est à ce moment que sont finalisées et maturées les fonctions physiologiques et comportementales individuelles et que la morphologie finale est acquise. Toute contrainte ou tout stress perçu par la progéniture pendant cette période peut avoir des conséquences morphologiques, physiologiques et/ou comportementales non négligeables à court mais aussi à long terme. In fine, c’est alors sa fitness qui peut être affectée par la qualité des conditions de développement subies. Ce doctorat vise à améliorer notre compréhension de l’importance des conditions environnementales abiotiques (climat, dérangement anthropique et exposition à un pesticide) et des soins parentaux rencontrés durant la croissance sur la qualité des poussins produits. Grâce à l’étude des marqueurs du stress et de l’allostasie (réponse au stress et longueur des télomères) chez des poussins d’Albatros à sourcils noirs et de Pétrel des neiges, nous avons pu démontrer, dans un premier temps, qu’à court terme, la qualité des soins parentaux – approximée par l’âge des individus reproducteurs – était un facteur très important pour la mise en place du phénotype du poussin. Dans un second temps, la manipulation des taux de corticostérone durant le développement chez des poussins de Moineau domestique (mimant une contrainte développementale) semble impacter à long terme les performances individuelles. En effet, à l’âge adulte, une réduction du métabolisme et des dépenses énergétiques, une réduction de l’attractivité sexuelle et une augmentation de l’investissement parental ont été mis en évidence. Au vu des résultats obtenus dans le cadre de ce doctorat, nous discutons de l’influence des conditions de développement sur la fitness des individus en s’appuyant sur les hypothèses évolutives détaillées dans la littérature scientifique
Post-natal development is a crucial step for the rest of life. Indeed, individual physiological and behavioral functions are set-up and matured during that life-stage and final morphology is acquired at that time. Any stress or constraint perceived by the offspring during this period can have significant morphological, physiological and/or behavioral consequences in the short but also in the long term. In fine, an individual’s fitness can be affected by the quality of its developmental conditions. This PhD aims to improve our understanding of the impact of abiotic developmental conditions (climate, human disturbance and exposure to a pesticide) and parental care on the quality of the produced chicks. Firstly, through the study of markers of stress and allostasis (stress response and telomere length) in Black-browed albatross and Snow petrel’s chicks, we demonstrated that in the short term, the quality of parental care - approximated by the age of the breeding individuals - was a major factor determining a chick’s phenotype. Secondly, the manipulation of corticosterone levels during development in House sparrow chicks (mimicking a developmental constraint) seems to have long-term impacts on individual performance. More precisely, in adulthood, I found that this experimental manipulation of developmental conditions was associated with a reduced metabolism, a reduced sexual attractiveness, and an increased parental investment during adulthood. Using the results obtained during this PhD, I discuss the influence of developmental conditions on individual fitness in an evolutionary context

La 6ème crise majeure d’extinction des espèces qui sévit actuellement n’épargne pas les oiseaux marins, notamment les albatros. Leurs populations ont chuté de 70% au cours des 60 dernières années essentiellement par mortalité dans les palangriers. Les grands albatros couvrent d’énormes distances pendant leurs trajets de recherche alimentaire et leur curiosité et leur opportunisme favorisent les rencontres régulières avec des bateaux. Ils constituent ainsi des modèles privilégiés pour étudier les relations entre les oiseaux marins et les pêcheries. Au cours de cette thèse, grâce au développement de nouveaux prototypes de balises déployés sur les albatros hurleurs et d’Amsterdam de l’océan Indien et à de nouvelles méthodes d’estimation du risque de captures accidentelles, nous avons pu démontrer que les comportements de recherche alimentaire naturels diffèrent de ceux associés à un bateau. De même, les caractéristiques intrinsèques des oiseaux (espèce, population, sexe, âge et personnalité) entrainent des différences d’exposition au risque de captures accidentelles notamment par l’utilisation d’habitats différents. Enfin nous avons mis en évidence que les caractéristiques des bateaux avaient également une forte influence sur ce risque de captures accidentelles, notamment par le type de bateaux rencontrés, leur légalité, les pratiques utilisées et la présence de rejets de pêche. Nous concluons par la présentation de nouvelles méthodes pour mieux estimer le risque de captures accidentelles et la nécessité de connaissances fondamentales des espèces et populations pour mieux protéger les milieux marins toujours plus en danger
The current 6th major species extinction crisis is also affecting seabirds, especially albatrosses. Their populations have decreased by 70% over the last 60 years, mainly due to mortality in longline fisheries. Large albatrosses cover enormous distances during their foraging trips and their curiosity and opportunism favour regular encounters with boats. Thus, they constitute privileged models for studying the relationships between seabirds and fisheries. During the course of this thesis, thanks to the development of new prototype loggers deployed on Wandering and Amsterdam albatrosses in the Indian Ocean and new methods for estimating by-catch risks, we were able to observe that natural foraging behaviours differ from those associated with a boat. Similarly, the intrinsic characteristics of birds (species, population, sex, age and personality) lead to differences in exposure to by-catch risk, particularly through the use of different habitats. Finally, we have shown that the characteristics of boats also have a strong influence on the risk of by-catch, in particular through the type of boats encountered, their legality, the fishing practices used and the presence of discards. We conclude by presenting new methods to better estimate the risks of by-catch and the need for fundamental knowledge of species and populations in order to better protect marine environments that are increasingly endangered

TESIS PARA OPTAR AL GRADO DE MAGÍSTER EN ADMINISTRACIÓN
Leopoldo Jiménez Herrera [Parte I], Xavier Ruiz Valls [Parte II]
En el siguiente Plan de Negocio se presenta una solución a un problema que tienen los padres durante la última etapa de embarazo y los primeros días de vida de los recién nacidos. Albatros es una organización que busca a través de un conjunto completo de servicios de cuidado, educación y acompañamiento para padres, reducir el stress que genera la llegada de un nuevo integrante a la familia. Para esto cuenta con un grupo de profesionales de la salud altamente capacitados y con una fuerte vocación de servicio al cliente, que a través de procedimientos estandarizados buscan apoyar y educar a los padres en la primera etapa de vida de los recién nacidos. Para el desarrollo del proyecto se requiere de una inversión inicial aproximada de $20 millones, que permitirán solventar las necesidades de compras en activos y cubrir los costos de capital iniciales. La inversión antes mencionada asegura resultados financieros con un VAN $37.140.609 a una tasa de descuento de 15,81%, una TIR 57,00% y un ROI de 472%, lo que hace bastante atractivo el modelo de negocios que se presentará y detallará a continuación.

Notre recherche concerne les domaines des EIAH (Environnements Informatiques pour l'Apprentissage Humain) et du CSCL (Computer Supported Collaborative Learning) et en particulier les situations de résolution collaborative de problème supportées informatiquement en synchrone et à distance. Nous avons considéré ces situations comme des situations de « travail collectif » telles que définie dans le CSCW (Computer Supported Cooperative Work), les apprenants étant mutuellement dépendants dans leur travail. Ces situations exigent de la part des apprenants, une activité de niveau supérieur visant à articuler leurs activités respectives. Il s'agit d'une structure abstraite qui émerge au cours de l'activité. Elle est évolutive et n'est pas prévisible. Ce concept d'auto-organisation peut être généralisé aux situations où un groupe d'apprenants doit réaliser une activité collective dont le processus n'est pas complètement prédéterminé. En particulier, dans le cas des situations qui mettent en jeu un challenge (ou défi) collectif. La prise en compte de ces dimensions organisationnelles est une question essentielle car elles ont un impact sur le processus global et elles conduisent les apprenants à s'engager dans des interactions productives de connaissances (par exemple, l'établissement d'un terrain d'entente, la planification, la résolution de conflit ou la régulation mutuelle, etc.). L'objectif de cette thèse est (1) de comprendre les éléments liés à l'organisation qu'il est important de supporter et (2) de concevoir un environnement informatique proposant (i) de supporter l'activité d' (auto)-organisation d'apprenants engagés dans un challenge pédagogique collectif et (ii) des moyens pour détecter et interpréter cette activité d'organisation afin de permettre à un tuteur de la supporter. A cette fin, nous avons supposé (1) qu'il était possible d'amener des apprenants engagés dans une activité collective à travailler explicitement sur l'organisation en leur proposant un problème, un scénario et des outils appropriés et (2) qu'il était possible de détecter, d'interpréter et d'agir dynamiquement sur l'activité d'organisation des apprenants. Les résultats de nos travaux de recherche nous permettent de proposer : 1. Une interprétation d'un modèle théorique (celui de Bardram [Bardram 98], issu du CSCW) en termes d'organisation et une instanciation de ce modèle, le modèle ALBATROM, dans le cas d'un challenge pédagogique collectif. 2. Un environnement informatique, ALBATROS et des outils spécifiques (COCOON et COCOOP) conçus en accord avec notre modèle ALBATROM. Ce système permet à des apprenants de résoudre collectivement un problème basé sur un défi. Il facilite l'explicitation de leur organisation tout en proposant les moyens de la faire évoluer dynamiquement au cours de l'action. 3. Une grille d'analyse qui a été élaborée en correspondance avec notre modèle et qui permet une meilleure compréhension de ce que font les apprenants en termes d'organisation. Cette grille permet une identification et une compréhension des moments critiques (pannes et changements de niveau dans l'organisation). Ceci afin de mettre à la disposition d'un éventuel tuteur des signaux visibles, interprétables selon notre modèle, utiles à son intervention. 4. L'analyse des résultats d'une expérimentation réalisée à partir de notre grille de codage et qui a pour objet de mesurer l'effet de notre système sur (1) l'organisation des apprenants, (2) sur la détection de cette organisation, et secondairement, (3) sur la résolution du problème et (4) sur la motivation des apprenants. 5. Un outil de gestion et de visualisation dynamique des traces pertinentes de l'activité d'organisation des apprenants présentes dans notre système permettant d'envisager un futur support semi-automatique de cette activité.

There are hundreds of thousands of fisheries-related mortalities of seabirds each year. Population trends for these species are highly influenced by changes in adult survival, their maximum growth rates are low, and little additional mortality can have a large impact on the population. As a result, many albatrosses and petrels are at risk of extinction, but limited demographic data makes it difficult to quantify the risk for many species. The goal of this research is to use population modelling tools to assess potential impacts with minimal data. In particular, the question of how much additional mortality a population can sustain is addressed when there is only knowledge of the adult survival rate, age at first breeding, and the number of breeding pairs. In this thesis, a simple decision rule designed for marine mammals is applied to albatrosses and petrels. In order to use this rule, adult survival, age at first breeding, a minimum estimate of the population size, and the maximum growth rate of the population are needed. While estimation of adult survival is well developed, work was required to calculate the other values from available data. A simple population model was developed to extrapolate from the number of breeding pairs to the total population size (given survival and age at first breeding); the effect of variable fecundity rates on the calculation of generation time and the maximum growth rate of a population was examined, relative to an estimate that only requires survival and age at first breeding; and a method for estimating the age at first breeding using capture-recapture data was suggested that accounts for study duration and emigration, in addition to capture probability. This work can help managers make better informed decisions when little is known about a population. For example, around 5,800 pairs of Gibson's albatrosses (Diomedea gibsoni) breed each year. Based on the work presented in this thesis, they may be able to sustain 1,000 - 1,200 additional mortalities per year. However, given concern about their conservation status, a mortality level below 100 - 120 is desired, and any mortality beyond that level suggests a need for more intensive management.

Cette thèse s’inscrit dans le contexte des changements globaux et du rythme accéléré d’extinction des espèces. Le but est de quantifier l’impact relatif des fluctuations climatiques et des activités humaines sur la démographie des populations. En particulier, les pêcheries industrielles font accidentellement, chaque année, des centaines de milliers de victimes parmi les oiseaux marins, notamment les albatros. Les réponses démographiques de quatre espèces d’albatros menacés de l’océan Austral (albatros à sourcils noirs, à bec jaune, fuligineux à dos sombre et grand albatros) sont comparées dans cette étude. Le succès reproducteur des quatre espèces a répondu de manière très contrastée aux anomalies climatiques selon la zone d’alimentation (subtropical, sub-Antarctique) et la saison (reproduction, hors-reproduction). La survie de toutes ces espèces a été canalisée contre les variations climatiques mais fortement affectée par les pêcheries palangrières au thon rouge du Sud sauf pour l’albatros à bec jaune dont le déclin serait majoritairement dû à la présence du choléra aviaire, cause d’une forte mortalité des jeunes poussins. Les pêcheries semblent avoir un impact plus important que les changements climatiques mais les interactions des effets climatiques et des pêcheries sont complexes. En outre, le réchauffement prédit pour la fin du 21ème siècle annonce la croissance de la population d’albatros à sourcils noirs de Kerguelen, à la condition que l’effort de pêche n’augmente pas tandis que celle des albatros fuligineux à dos sombre continuerait son déclin même dans le cas d’un arrêt de la pêche. Il paraît donc nécessaire de prédire les conséquences futures du réchauffement et des activités humaines sur des espèces menacées comme les albatros.

Cílem práce je vytvoření souhrnného přehledu o metrikách jakosti a ekonomické efektivnosti softwarových produktů a prakticky je aplikovat. V první části práce ? teoretické, je vytvořen souhrn a sumarizace dostupných metrik (ukazatelů), které jsou při hodnocení systémů využívány. Součástí je přehled o jednotlivých vlastnostech metrik (ukazatelů). Druhá část je zaměřena na popis informačních systémů Albatros a GICR. Ve třetí části ? praktické, je provedena aplikace vybraných metrik (ukazatelů). V poslední kapitole třetí části je provedeno komplexní zhodnocení systému a rozhodnutí o jeho vhodnosti pro splnění stanovených požadavků. Výsledkem provedené analýzy IS je doporučení pro investici do systému Albatros.

Thesis (Ph.D.) - University of Glasgow, 2008.
Ph.D. thesis submitted to the Division of Environmental and Evolutionary Biology, Institute of Biomedical and Life Sciences, University of Glasgow, 2008. Includes bibliographical references. Print version also available.

Os albatrozes e petréis (Procellariiformes) são aves oceânicas e migratórias de grande interesse conservacionista. Neste trabalho foram estudadas duas classes de poluentes bastante conhecidos por afetarem negativamente as aves marinhas: os poluentes orgânicos persistentes e os plásticos. Bifenilos policlorados (PCBs) e pesticidas organoclorados foram detectados no tecido adiposo, fígado e músculo de oito espécies de Procellariiformes. Apesar da grande variabilidade intraespecífica nas concentrações, os perfis de PCBs e pesticidas organoclorados foram semelhantes entre os indíviduos, com predôminância de PCBs penta, hexa e heptaclorados e do p´p-DDE. A condição corporal se mostrou um fator importante na variação e redistribuição dos organoclorados nos tecidos das aves. As análises de isótopos estáveis de carbono e nitrogênio no fígado e músculo das aves mostraram que a dieta não foi suficiente para explicar as concentrações de organoclorados nas espécies estudadas e reforçaram a influência de fatores como idade, distribuição e especifidade da dieta na contaminação por estes compostos em aves marinhas. PCBs e pesticidas organoclorados foram detectados em pellets e fragmentos plásticos encontrados no trato digestório das aves estudadas, com perfis semelhantes aos encontrados nos tecidos dos Procellariiformes. A ocorrência de poluentes orgânicos em plásticos evidencia a capacidade destes de adsorver e transportar estes compostos e reforça o potencial dos plásticos como uma fonte adicional de contaminação para os animais que os ingerem, como as aves marinhas.
Albatrosses and petrels (Procellariiformes) are migratory oceanic birds of considerable conservational interest. The aim of the present study was to evaluate two classes of pollutants that negatively affect seabirds: persistent organic pollutants and plastics. Polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) were detected in the adipose tissue, liver and muscle of eight species of Procellariiformes. Although organochlorine concentrations exhibited a high degree of intra-species variability, the profiles of PCBs and OCPs were similar among the individuals, with predominance of penta, hexa and heptachlorobiphenyls and p´p-DDE. Body condition was an important factor in the variation and redistribution of organochlorine compounds in the tissues of the birds. Stable isotope analysis of carbon and nitrogen in the liver and muscle revealed that diet alone was insufficient to explain the organochlorine concentrations in the species studied, suggesting the influence of factors such as age, distribution and diet specificity regarding organochlorine contamination in seabirds. PCBs and OCPs were detected in plastic fragments and pellets found in the digestive tract of Procellariiformes, with profiles very similar to those found in the tissues of the birds. The occurrence of organic pollutants in plastics demonstrates their ability to adsorb and transport these compounds and underscores the potential of plastics as an additional source of contamination in organisms that ingest these products, such as seabirds.

Moult is an energetically demanding process for birds, and the replacement of flight feathers impacts flight performance. As a result, few birds overlap moult with other key activities such as breeding or migrating. Feather growth rates show little change in relation to body size, so large birds with long flight feathers take a long time to grow individual feathers, making their moult even more challenging. Unless these birds can afford to become flightless for several weeks while they replace all their flight feathers simultaneously, many large birds lack sufficient time to breed and replace all their wing feathers each year. As a result, they have evolved complex moult strategies that replace a subset of feathers each year. Albatrosses and giant petrels are prime examples of birds facing this challenge. This study focusses on Wandering Albatrosses (Diomedea exulans) and Northern Giant Petrels (Macronectes halli) breeding at Marion Island and Southern Giant Petrels (M. giganteus) at Gough Island. I explore primary and secondary moult patterns in Wandering Albatrosses and secondary and greater secondary coverts in giant petrels in relation to breeding activity. I used digital photography to record the wear patterns in the wings of Wandering Albatrosses and giant petrels. Using photographs of upperwings of marked individuals over time allowed the opportunity to track changes in the wear pattern among specific feathers, although scoring feather wear from images works better for darker feathers. The rate of wear among secondaries and their coverts differed across the wing, with the inner feathers wearing faster than the central feathers. Photographing the extended wings of albatrosses and petrels incubating eggs had no impact on hatching success. Using this method I was able to test the often held assumption that wing feather moult is largely symmetrical. In Wandering Albatrosses, moult symmetry was greatest in outer flight feathers, especially primaries. However, the pattern of increasing asymmetry towards the body was not consistent; inner primaries showed less symmetry than outer secondaries and inner secondaries were moulted with greater symmetry than central secondaries. Giant petrels preferentially replaced the inner and outer secondaries and the inner and outer greater secondary coverts, and feather symmetry was greatest in these feathers. All three species indicated some asymmetry in all feathers that had an incomplete annual 2 moult. Depending on the question being asked, I recommend scoring both wings when investigating moult patterns. Wandering Albatrosses typically take a sabbatical year following a successful breeding attempt, and thus failed breeders usually have less time to moult between successive breeding attempts. Following a successful breeding attempt, Wandering Albatrosses from Marion Island replaced a similar number of primary feathers on average (males 7.9 and females 7.3) as birds from the Crozet Islands (males 8.8 and females 8.1) and South Georgia (males 8.6 and females 7.1). Wandering Albatrosses that do not skip a year following a failed breeding attempt, not only replaced fewer feathers on average, but showed a difference in number of feathers replaced between sexes at Marion Island (males 7.4, females 6.1), as previously reported at the Crozet Islands (males 8.3, females 6.5) and South Georgia (males 7.2, females 5.2). These results suggest that females are under greatest pressure when a breeding attempt fails. Because females from South Georgia replace fewer feathers, especially following a failed breeding attempt, they might be under more stress than females from populations breeding at islands in the Indian Ocean (Marion and Crozet). This parallels the contrasting population trends in these regions, with numbers increasing over the last few decades in the Indian Ocean (Marion and Crozet Islands) but decreasing steadily at South Georgia. General Linear Models (GLMs) showed that sex and time available to moult both influenced the number and mass of flight feathers replaced. Sex explained more variation in terms of number of feathers replaced (67%) than time available to moult (33%), but time available to moult explained 68% of the mass of flight feathers replaced. However, there is large variation among birds in the number of primaries and secodaries replaced, independent of time available for moult. Together, sex and time available to moult accounted for only 9.2% (number) and 11.9% (mass) of the variance in feathers replaced. Giant petrels are one of the largest birds that undergo a complete primary moult each year without losing the ability to fly. They do this by overlapping their moult with breeding and by moulting several primaries at once. Being annual breeders, individuals that fail a breeding attempt have more time to moult than successful breeders, and therefore replaced more flight feathers. Northern Giant Petrels having a successful breeding 3 attempt replaced on average the same percentage of secondary and greater secondary coverts in both sexes; Following a successful breeding attempt Southern Giant Petrels (both sexes) replaced more feathers (secondaries and greater secondary coverts) than Northern Giant Petrels. I found that in a failed breeding attempt giant petrels have more time to moult and therefore replaced more secondary feathers than successful breeders. GLMs showed that breeding outcome was the only variable that influenced the mass of feathers replaced in Northern Giant Petrels, accounting for 14% of the variance in feathers replaced, while sex was the only variable in Southern Giant Petrels, accounting for 6% of variance. When both species were modelled together with sex and breeding attempt as explanatory variales, only breeding attempt was significant, accounting for 11% of the variance in the mass of secondaries and coverts replaced. In summary, the assumption that breeding activity, and thus the time between breeding attempts, influences the extent of moult in large birds with incomplete wing moults was supported for Wandering Albatrosses and Northern Giant Petrels. However, time available for moult explained only a small proportion of individual variation in moult extent in these species. Southern Giant Petrels replaced a similar mass of flight feathers, irrespective of breeding outcome. My results suggest that factors other than time between breeding attempts are important in determining the extent of wing moult. My study highlights the important tradeoffs large birds are required to make when balancing moult and reproduction. Annual monitoring of moult patterns in known individuals provides a valuable tool to better understand moult patterns in these large, long-lived birds.

L’océan Austral est soumis à la redistribution globale des contaminants par les voies atmosphérique et océanique. Cependant, la contamination des écosystèmes austraux est très peu connue, en particulier dans le secteur Indien. De par leur toxicité, leur mobilité et leur capacité à se bioaccumuler dans les tissus des organismes et à se bioamplifier dans les réseaux trophiques, le mercure (Hg) et les polluants organiques persistants (POPs) comptent parmi les contaminants les plus préoccupants. Du fait de leur position élevée dans les réseaux trophiques, les oiseaux marins sont exposés à de grande quantités de contaminants par la voie alimentaire. En conséquence, ils sont souvent utilisés comme bioindicateurs de l’état de contamination des écosystèmes, par le biais des plumes et du sang, qui peuvent être échantillonnés de façon non destructive. Ma thèse s’est intéressée aux nombreuses espèces d’oiseaux marins (plus de 40) qui nichent au sein des Terres Australes et Antarctiques Françaises, au sud de l’Océan Indien, afin de décrire et expliquer les niveaux de contaminants le long d’un large gradient latitudinal, de l’Antarctique à la Zone Subtropicale, et d’identifier les meilleures espèces bioindicatrices pour un suivi à long terme de la contamination de ces écosystèmes. Au cours d’une première étape méthodologique, les manchots et les poussins de toutes les espèces ont été identifiés comme de bons bioindicateurs de contamination puisque, à la différence de la plupart des oiseaux adultes, ils présentent une faible variabilité des niveaux de contaminants dans les plumes. Au cours d’une seconde étape explicative, l’effet de facteurs intrinsèques (traits individuels) et extrinsèques (écologie alimentaire déduite grâce à la méthode des isotopes stables) sur les niveaux de contaminants a été évalué dans les plumes des oiseaux de la communauté de Kerguelen (27 espèces) et dans le sang du grand albatros de Crozet (180 individus dont les traits de vie sont connus). L’écologie alimentaire s’est avérée être le principal facteur explicatif des niveaux de contaminants, tandis que l’âge, le sexe, la phylogénie et le statut reproducteur jouent un rôle mineur. La classe d’âge est néanmoins un facteur à prendre en compte, puisque les poussins montrent souvent des concentrations inférieures aux adultes. Au cours d’une troisième étape, les variations spatio-temporelles de la contamination ont été étudiées en utilisant une sélection d’espèces bioindicatrices et en tenant compte de leur écologie alimentaire. Plusieurs résultats portant sur différentes espèces (oiseaux océaniques) et populations (poussins de skua) ont montré que, contrairement aux prédictions, l’exposition des oiseaux au Hg augmente graduellement des eaux antarctiques aux eaux subantarctiques puis aux subtropicales, alors que l’exposition aux POPs, en accord avec la théorie de la distillation globale, montre la tendance inverse. D’autre part, la comparaison des concentrations en Hg dans les plumes de manchot, effectuée entre des spécimens de musée et des échantillons actuels, indique que leur exposition au Hg n’a pas changée depuis les années 1950-1970. Toutefois, des espèces subantarctiques montrent une tendance à la hausse. De futures études devraient viser à l’utilisation des plumes comme tissu de référence pour l’évaluation et le suivi de la contamination des écosystèmes, en particulier en ce qui concerne les POPs. Parmi les nombreuses espèces étudiées au cours de ces travaux de thèse, les bioindicateurs les plus pertinents se révèlent être le manchot empereur et le pétrel des neiges (Antarctique), le manchot royal, le pétrel bleu et l’albatros à sourcil noirs (subantarctique), le gorfou sauteur subtropical et l’albatros à bec jaune (subtropical). Le suivi à long terme de ces espèces permettra d’évaluer l’évolution temporelle de l’état de contamination de l’océan Austral
Antarctic and subantarctic marine environments are reached by inorganic and organic contaminants through ocean circulation and atmospheric transport. Yet, environmental contamination is poorly known in the Southern Ocean, in particular in the Indian sector. Among environmental contaminants, mercury (Hg) and persistent organic pollutants (POPs) are primarily of concern, because they are toxic, highly mobile, and they bioaccumulate in the tissues of living organisms and biomagnify up the food web. Seabirds, as upper predators, are exposed to large quantities of contaminants via food intake and have widely served as biomonitors of marine contamination, notably through the non-destructive sampling of their feathers and blood. My doctoral work has focussed on the abundant and diverse seabird species (more than 40) breeding in the French Southern and Antarctic Lands, southern Indian Ocean, in order to describe and explain contaminant concentrations over a large latitudinal gradient, from Antarctica to the subtropics, and to identify the best bioindicator species for contaminant biomonitoring. In a first methodological step, seabirds with synchronous moult of body feathers (adult penguins and chicks of all species) were recognised as good candidates as bioindicators, because, unlike most adult birds, they present low within-individual variation in feather contaminant concentrations. In a second explanatory step, the influence of intrinsic (individual traits) and extrinsic factors (feeding ecology inferred from the stable isotope method) driving variation in contaminant concentrations was evaluated in feathers of the large avian community of the Kerguelen Islands (27 species) and in blood of wandering albatrosses from the Crozet Islands (180 birds of known individual traits). Feeding ecology was the main factor driving variation in contaminant concentrations of blood and feathers, both at the community, population and individual levels, whereas age, sex, phylogeny and breeding status played a minor role. Age-class was however an important intrinsic factor to consider, with chicks usually having lower concentrations than adults. In a third step, spatio-temporal patterns of contamination were studied through selected bioindicator species and by taking into account their feeding habits. Results from different species (oceanic seabirds) and populations (skua chicks) showed that, contrary to predictions, Hg exposure gradually increases from Antarctic to subantarctic and subtropical waters, whereas, in accordance with the global distillation theory, POPs exposure has the opposite pattern. Comparisons between penguin feathers from museum collections and contemporary samples showed that bird exposure to Hg is overall not different today when compared to 50-70 years ago, but subantarctic species are possibly experiencing an increasing trend. Future research efforts should be focussed on the use of feathers as biomonitoring tools, in particular for POPs determination. The best recommended bioindicator species include the emperor penguin and snow petrel (Antarctic), king penguin, blue petrel and black-browed albatross (subantarctic), and northern rockhopper penguin and Indian yellow-nosed albatross (subtropical). Future biomonitoring studies on these species will give invaluable insights into the poorly-known temporal trends of environmental contamination in the Southern Ocean

Cette thèse étudie les effets liés à l'âge et plus particulièrement liés à la sénescence chez deux espèces extrêmement longévives: l'albatros à sourcils noirs (Thalassarche melanophrys) et le grand albatros (Diomedea exulans). Dans un premier temps nous cherchons à déterminer quelles sont les variations de différents traits d'histoire de vie, démographiques et morphologiques en fonction de l'âge. Une approche multi-traits et multi-états nous permet de modéliser les variations des traits avec l'âge en prenant en compte les effets liés au sexe ou au statut reproducteur de l'année précédente dans des modèles de capture-recapture. Dans un second temps, nous relions ces patrons âgedépendants aux variations de l'environnement en terme de fluctuations climatiques, océanographiques et d'activités anthropiques (pêche industrielle), afin de déterminer si en fonction de leur âge, les individus sont influencés de manière différentielle. Enfin les variations différentielles identifiées des traits démographiques dues aux fluctuations environnementales selon l'âge sont intégrées dans des modèles matriciels de populations afin de déterminer si et comment les événements extrêmes peuvent altérer la dynamique et la structure des populations. Ce travail basé sur des données longitudinales et transversales collectées depuis plus de 50 dans les Terres Australes et Antarctiques Françaises apporte des éléments nouveaux sur l'écologie évolutive de la sénescence en milieu naturel et comment l'âge peut influencer la réponse des populations aux changements globaux chez ces espèces fortement menacées d'extinction.

Seabird populations breeding within the Southern Ocean have experienced various threats over the past few decades. Albatrosses are particularly at risk due to several factors, inter alia, accidental bycatch on fishing gear, ingestion of polluted marine debris, invasive predatory species at breeding sites, as well as climate change-induced alterations to ocean circulation patterns. The recent decline in many albatross populations is mainly attributed to incidental fishing mortality, which decreases adult as well as juvenile survival rates and is thus detrimental to these long-lived, low fecundity birds. Recently, changes in fishing regulations to require the use of various mitigation measures have reduced the number of seabirds killed by fishing vessels. However fisheries may still impact seabirds either by direct competition for the same prey, or through ecosystem cascades arising from the removal of predatory fish and squid. Sub-Antarctic islands are important breeding grounds for many seabirds, including albatrosses. Monitoring of seabirds breeding on sub-Antarctic islands is important to detect changes in population dynamics to be able to implement timely conservation measures. Marion Island, the larger of the two Prince Edward Islands, some 2000 km southeast of South Africa, is a breeding site for four albatross species including the sooty (Phoebetria fusca) and light-mantled albatrosses (P. palpebrata). The Prince Edward and Crozet Islands are the only places where both Phoebetria albatrosses breed sympatrically in substantial numbers. Both archipelagos are 46°-47°S, at the southern and northern limit for sooty and light-mantled albatrosses, respectively. At-sea observations and diet studies suggest that sooty albatrosses forage mainly in sub-tropical waters to the north and light-mantled albatross in Antarctic or sub-Antarctic waters to the south. The sooty albatross is listed as Endangered due to recent global population declines whereas the light-mantled albatross is Near-threatened. The only comprehensive study of these species at the Prince Edward Islands was conducted during the late 1970s but annual estimates of breeding populations have been made from 1996 onwards. The previous analysis of these counts, up to 2008, suggested that the sooty albatross population on Marion Island decreased from 1996 to 2008, whereas numbers of light-mantled albatrosses increased over this period. Extending the count series to 2014, trends for both species were reversed, with sooty albatrosses recently increasing and light-mantled albatrosses decreasing. However, the timing of sooty albatross counts is in question as these were done towards the end of the incubation period when many nest failures have already occurred. Breeding success of both Phoebetria albatrosses was estimated during 2013/14 and 2014/15. The success of sooty albatrosses (51% overall) was higher than estimated at Marion Island in the 1970s (19%), but it was still lower than that of a neighbouring colony on Possession Island, Crozet archipelago (65%). The sooty albatross success was however skewed by a sub-colony with a very low 5 breeding success; excluding this sub-colony the breeding success is similar to that of the Crozets. Light-mantled albatross breeding success was the same as past estimates and lower than colonies at Macquarie and Possession Islands. Additional monitoring of a sub-sample of nests within the monitoring colonies was done to determine incubation and brood guard (light-mantled albatross only) shift lengths for both species. The shift lengths and distributions were not significantly different from previous data on Marion Island or other breeding sites.

Cette thèse s'attache à expliquer les relations entre les variations de l'environnement et les populations de Procellariiformes (albatros et pétrels) du sud de l'Océan Indien, en étudiant leurs stratégies d'exploitations et d'allocation des ressources. Dans ce système, la recherche alimentaire est fortement contrainte par deux facteurs : le milieu présente une distribution des ressources avec une structure très hétérogène et morcelée (en "patch") et les oiseaux doivent faire durant la reproduction des allers-retours entre les zones d'alimentation et les sites de nidification sur parfois plusieurs milliers de kilomètres. Les albatros ajustent leurs déplacements à ces deux contraintes en concentrant leur effort de recherche sur les zones où les ressources semblent prévisibles à méso-échelle (c. 100km), après un déplacement rapide où l'effort est faible. Cet ajustement est dépendant de l'échelle de structure du milieu (taille des patches) et implique une connaissance des zones prévisibles à fortes densités de proies. Face aux importantes variations inter-annuelles dans la distribution et l'abondance des ressources, ils présentent une flexibilité dans leurs ajustements de recherche, mais au dépend de la reproduction en cours. Le rôle régulateur est rempli par les réserves énergétiques, qui modulent l'impact des variations de ressources sur la survie des adultes au détriment de la reproduction engagée, préservant ainsi leur forte valeur reproductive résiduelle. Les variations de la distribution des ressources exploitées et leur prévisibilité (notamment à méso-échelle), ainsi que la capacité à tamponner ces variations, par un faible coût énergétique de recherche et par une disposition au jeûne prolongé, sont déterminantes pour expliquer les variations du succès reproducteur et les stratégies démographiques observées chez ces espèces
This study concerns the relationships between environmental variability and populations of Procellariiforms in the south Indian Ocean, through their foraging ecology and allocation processes. Two major constraints affect the observed strategies: the patchy, heterogeneous resource distribution and the central-place constraint. All of six species of albatrosses and one of large petrel species adjust their foraging movements to the environment structure, by presenting an Area-Restricted Search (ARS) behaviour accordingly to patch scale sizes. The occurrence and the magnitude of this behaviour influence the foraging efficiency, probably in relation to resource density on patch. Facing to high inter-annual variability in resource abundance and distribution, albatrosses are able to adapt their foraging behaviour, but this flexibility can lead to breeding failure or low chick growth. Allocation decisions are mediated by body condition under the influence of the foraging efficiency, allowing to preserve adult survival and their high residual reproductive value when low resource conditions are occurring. Predictability in distribution and abundance of the resource exploited, but also foraging energetic costs and fasting capabilities, seem to be important to explain the variations observed in breeding success and ultimately demographic strategies of these Procellariiforms

Two sympatric Phoebetria albatrosses, P. fusca and palpebrata breeding at Marion Island in the South Indian Ocean were studied. Adult individuals were tracked between 2008 and 2011. The study examined the foraging distribution of the two species in relation to environmental parameters such as sea surface temperature. Interaction with mesoscale features expressed by sea surface temperatures, was tested with statistical models. Tracked P. fusca demonstrated positive association with sea surface temperatures in the Southern Indian Ocean, in particular during incubating and chick-provisioning periods, by travelling shorter distances to the interfaces of mesocale features created as a result of the Agulhas Return Current located << 500 km to the north of breeding islands. During nest construction, tracked P. fusca travelled greater distances in search of food possibly because they had no chick to return to at the colonies. Contrastingly, tracked P. palpebrata did not demonstrate any positive association with sea surface temperatures. During incubating and chick-provisioning periods, tracked P. palpebrata travelled shorter distances to foraging grounds located to the south of breeding islands possibly to maximise returns to chicks while minimising efforts. During nest construction, tracked P. palpebrata travelled to distant foraging grounds to the south of the Antarctic Polar Front in areas of low mesoscale variability suggesting that greater distances can be achieved when they have no chick to feed at the colonies. Individuals of both tracked species foraged within close proximity during energy-demanding periods indicating their ability to employ an efficient foraging strategy that ensures minimal effort whilst maximising returns. Generalised Linear Models with the response variable being species and explanatory variables comprised of sea surface temperatures, annual breeding stages, distance traversed and activity, were conducted to examine the effect of environmental factors on seabird foraging distribution. These models were subjected to robust fitness tests and those that represented ecological reality of the two tracked albatrosses were chosen. The study demonstrates that the most important foraging areas for these two tracked seabird species overlap with the Indian Ocean Tuna Commission Convention area making them vulnerable from incidental capture from high longline fisheries. These results have implications to the conservation of these albatrosses suggesting a need for a multi-faceted approach on fisheries management particularly on mitigation of seabird bycatch in the Indian Ocean Tuna Convention area.

Le stade juvénile chez les animaux demeure souvent une période mystérieuse aux yeux des scientifiques. La survie juvénile est pourtant un facteur déterminant du futur des populations. Les animaux juvéniles sont connus pour leur mortalité importante durant les premiers mois après l’indépendance et leur taux de survie augmente avec l’âge. La théorie suppose d’une part que les juvéniles ont des capacités de survie moindres que celles des adultes. Ils seraient peu efficaces dans leur recherche de nourriture et auraient besoin d’une période d’apprentissage pour être capables de supporter les couts associés à la reproduction. De plus, des facteurs proximaux telles que les fluctuations environnementales et la compétition affectent également la survie des juvéniles. Des études sur les oiseaux terrestres, ont permis d’obtenir de nombreuses informations grâce à la possibilité de faire des observations directes et récemment des études télémétriques. Cependant collecter des données en milieu marin s’avère compliqué, en particulier lorsque l’on s’intéresse aux juvéniles. Les oiseaux marins longévifs ont en commun la longue durée de leur période d’immaturité (jusqu’à plus de 10 ans). Les jeunes, à l’indépendance, se dispersent seuls en mer durant plusieurs années, ne revenant à terre que pour se reproduire une fois adulte. Ainsi, les suivre durant leurs premiers mois afin de comprendre leurs comportements et leur écologie alimentaire constitue un véritable défi. Dans ce contexte, cette thèse a pour objectif d’élucider au moins en partie le mystère de la vie juvénile des oiseaux marins. Grâce à des technologies bio-télémétriques nous avons pu suivre par satellite un large panel de juvéniles de neuf espèces proches d’albatros et pétrels (procellariiformes) se reproduisant dans les Terres Australes et Antarctiques Françaises de l’Océan Austral : les îles Crozet, Kerguelen et Amsterdam. Les trajectoires ont été analysées grâce à différentes méthodes statistiques permettant de décrire les mouvements, le comportement alimentaire et les répartitions spatiales des jeunes après leur envol, le tout en lien avec les conditions environnementales. Les résultats obtenus sont discutés à la lumière de la comparaison avec les adultes des mêmes espèces. Grâce à ce jeu de données j’ai étudié les stratégies de dispersion des jeunes inexpérimentés qui quittent le nid. J’ai montré que ces stratégies ainsi que la proportion d’inné les contrôlant sont très variables selon les espèces et suivent ou non celles des parents selon les espèces. Le taux de variabilité dans les stratégies juvéniles peut refléter leur potentielle plasticité et leur capacité à répondre à des changements de l’environnement et in fine affecter la dynamique des populations. Par ailleurs, l’analyse de trajectoires de juvéniles de grand albatros a révélé qu’en plus de leurs capacités innées ils apprennent très rapidement les compétences de base requises pour survivre en mer puis optimiser leur recherche alimentaire. Cependant des différences perdurent par rapport aux adultes, suggérant que d’autres comportements non-observables (via nos données) nécessitent une période d’apprentissage plus longue. Enfin, quelle que soit la stratégie adoptée, elle semble en partie contrainte par la compétition intraspécifique avec les individus plus âgés puisque les juvéniles limitent celle-ci via une ségrégation spatiale. Ce dernier point souligne le besoin de prendre en compte la répartition spatio-temporelle âge-dépendante des espèces lorsque l’on veut mettre en œuvre des mesures de protection pour ces espèces. Ces travaux apportent de nouvelles connaissances sur plusieurs des aspects majeurs de l’écologie en mer d’individus inexpérimentés cherchant leur nourriture seuls dans un environnement hautement imprévisible. Nous apprenons ici comment de l’instinct et de l’expérience découlent des stratégies de vie juvéniles qui permettent aux oiseaux de survivre dans un environnement inconnu
The juvenile stage of animals is often much of a mystery to scientists. Moreover, juvenile survival is known to be a strong determinant for the future of a population. Indeed, juvenile animals are known to face high mortality during the first months after independence, with survival rates improving with age. One ultimate hypothesis implies that juveniles have a lower survival rate than adults because of their lack of experience. Thus they are initially poor foragers and require a learning period (immaturity) to improve their efficiency before being able to bear breeding and its associated energetic costs. Proximal factors also influence juvenile survival, such as environmental fluctuations and competition. Studies on terrestrial animals have provided useful information thanks to the possibility of direct observation and, recently, bio-logging technologies. However, collecting data in the marine environment is more difficult, particularly when juveniles are concerned. Long-lived marine species such as seabirds have an extensive immature period extending from a few years up to more than ten years. The offspring of these species will usually leave their natal site and disperse at sea for several years before returning to breed on land, most of the time at their place of birth. This makes it difficult to obtain direct observations, and so documenting their first journey at sea to learn more about their behavioural and foraging ecology is a challenge. In this context, this PhD aims to unravel at least part of the mystery of juvenile seabirds’ early life by investigating the first months at sea of newly fledged individuals from several long-lived species of procellariiformes. Using state of the art advancements in biotelemetry, I was able to follow, at sea, by satellite a large set of juveniles from nine closely related species of albatross and petrel breeding in the French Southern Territories of the Southern Ocean : Crozet, Kerguelen and Amsterdam Islands. Some of these species had never been tracked before. Trajectories were analysed using various new statistical methods that allowed movement strategies, alongside foraging behaviour and spatial distributions, to be described, all in tight link with environmental conditions. The findings were discussed in the light of a comparison with adults of the same species. Using this huge dataset I first examined the dispersal strategies of young birds that had left their nest and were totally independent from their parents. I showed that the strategies, as well as the amount of innate information controlling them are highly variable depending on species. Their movements take them in various habitats following or not the parental strategies. The amount of variability in juvenile strategies is linked to potential plasticity when facing environmental changes. These parameters are related to the history life trait of species, and might affect demography and population dynamics. In addition, by analysing juvenile wandering albatross tracks I showed that although they quickly learn the basics of flight and foraging optimization required to survive at sea, behavioural differences with adults persist in time, suggesting that non-observable behaviours need a longer period of learning and memorisation. Finally, whatever the strategy adopted, it seems to be driven in part by intraspecific competition since juveniles mitigate competition with older birds by segregating spatially. This last point highlights the crucial need of acknowledging age-related distribution when making management decisions to protect seabird populations. This work provides new insights about several major aspects of the at-sea ecology of naïve individuals foraging alone in a highly unpredictable environment. We learn here how instinct followed by experience shape specific early life strategies that allow young birds to deal with environmental conditions and interspecific competition so as to be able to survive

This study analyses the presence of more-than-human beings, particularly animal figurations, in two works of diverse literary genres, namely: the poem “The albatross”(1861) by Charles Baudelaire and the short story “The house of Asterion”(1947) by Jorge Luis Borges through the lens of theories on the animal turn. Previous studies on both the poem and the short story analyzed the animal (albatross and minotaur) in allegorical or metaphorical terms emphasizing a human-centered perspective.However, this study maps an encounter between voice (human and hybrid) and the more-than-human being beyond rhetorical figures, that is, seeking material and affective sites of contact that speak of a continuum between entities deemed ontologically different. Analyzing the mentioned literary works through Guarramuño`s concept of worlds in common, in both the poem and the short story, we identify that certain aspects of the voice act as a shared space in which the materiality of the more-than-human being encounters the human and in which both beings exhibit a common affective pattern. Subsequently, through Derrida`s idea of distance-closenesswe analyze aspects of the voices that cross the animal-human border, where the language is revealed as a false superiority with respect to other forms of communication beyond the human word. In this respect, the analysis reveals an affective zone where uncertainty marks the encounter between human and animal, bringing closer animal an human domains. Our study revealsthat, both in the poem and the short story, however precarious and limited, the encounter between human voices and animal can be said to go beyond rhetorical figures. Indeed, this encounter reveales in this study as an affective continuum in the relationship between voices and more-than-human beings, which questions the opposition human-animal and therefore the superiority of the human regarding other sentient beings

Peu de données sont actuellement disponibles sur les effets de l'âge sur les performances physiologiques et comportementales des animaux sauvages. Compte tenu de sa nature multifactorielle, il est délicat d'explorer les corrélats physiologiques et comportementaux de la sénescence en conditions naturelles sans mener une approche multidisciplinaire. Le but de cette thèse est de mettre en oeuvre une telle approche pour analyser simultanément les effets de l'âge sur la physiologie, les comportements de recherche alimentaire et le succès reproducteur chez deux oiseaux marins longévifs, le Grand Albatros Diomedea exulans (2-48 ans) et le Pétrel des Neiges Pagodroma nivea (7-46 ans). Nous avons conduit des études transversales pour décrire les patrons de variation avec l'âge du comportement de recherche alimentaire, de la performance de reproduction et de nombreux marqueurs phénotypiques associés au vieillissement chez l'Homme ou les animaux de laboratoire, tels que l'immunité, le stress oxydant, les défenses antioxydantes, les taux basaux de d'hormones, la réponse hormonale au stress et la réponse cardiaque au stress. Chez le Grand Albatros, nous avons détecté un effet de l'âge sur le comportement de recherche alimentaire, la réponse au stress et le succès reproducteur, mais pas sur les marqueurs basaux de l'immunité, du stress oxydant ou des taux hormonaux. Les vieux Albatros mâles montrent une ségrégation avec l'âge dans les aires de pêche, sont moins actifs à la surface de l'eau, parcourent de plus grandes distances, et reviennent de mer avec des taux relatifs d'hormone de stress élevés. En revanche, aucun effet de l'âge été détecté sur la physiologie ou le comportement des femelles, suggérant que les patrons de variations avec l'âge sont propres à chaque sexe, comme chez l'Homme ou les animaux de laboratoire. En outre, l'examen des albatros non reproducteurs suggère que c'est en situation de contrainte que les patrons de variation avec l'âge des traits physiologiques s'expriment. Chez le Pétrel des neiges, aucun effet de l'âge n'a été détecté sur la réponse immunitaire humorale, sur l'augmentation des taux d'hormone de stress pendant la réponse immunitaire, sur la croissance ou la réponse au stress des poussins, suggérant qu'il est difficile de mettre en évidence des corrélats physiologiques de la sénescence chez cette espèce longévive. Dans l'ensemble, nos résultats suggèrent que (i) les niveaux de maintenance somatique restent élevés jusque dans la fin de vie, contrairement aux espèces peu longévives, ce qui va dans le sens de la Théorie du Soma Jetable ; (ii) les traits phénotypiques associés aux comportements alimentaires pourraient être des facteurs proximaux du vieillissement en conditions naturelles ; (iii) le sexe est un paramètre majeur de la détermination des patrons de variation avec l'âge en conditions naturelles.

Peu de données sont actuellement disponibles sur les effets de l'âge sur les performances physiologiques et comportementales des animaux sauvages. Compte tenu de sa nature multifactorielle, il est délicat d'explorer les corrélats physiologiques et comportementaux de la sénescence en conditions naturelles sans mener une approche multidisciplinaire. Cette thèse de terrain constitue le premier travail multidisciplinaire abordant la question cruciale du vieillissement en conditions naturelles. Notre but est d'analyser simultanément les effets de l’âge sur la physiologie, les comportements de recherche alimentaire et le succès reproducteur chez deux ‘modèles d’étude’ du vieillissement : le Grand Albatros Diomedea exulans (2-48 ans ; île subantarctique de Crozet) et le Pétrel des Neiges Pagodroma nivea (7-46 ans ; Terre Adélie, Antarctique). Nous avons conduit des études transversales pour décrire les patrons de variation avec l'âge du comportement de recherche alimentaire, de la performance de reproduction et de nombreux marqueurs phénotypiques (associés au vieillissement chez l'Homme ou les animaux de laboratoire), tels que l'immunité, le stress oxydant, les défenses antioxydantes, les taux basaux de d'hormones, la réponse hormonale au stress et la réponse cardiaque au stress. Chez le Grand Albatros, nous avons détecté un effet de l’âge sur le comportement de recherche alimentaire, la réponse au stress et le succès reproducteur, mais pas sur les marqueurs basaux de l'immunité, du stress oxydant ou des taux hormonaux. Les vieux Albatros mâles ont des aires de pêche différentes de celles des mâles plus jeunes, sont moins actifs à la surface de l’eau, parcourent de plus grandes distances, et reviennent de mer avec des taux relatifs d'hormone de stress plus élevés que les jeunes. En revanche, aucun effet de l'âge été détecté sur la physiologie ou le comportement des femelles, suggérant que les patrons de variations avec l'âge sont propres à chaque sexe, comme chez l'Homme ou les animaux de laboratoire. En outre, l'examen des albatros non reproducteurs suggère que c'est en situation de contrainte que les patrons de variation avec l'âge des traits physiologiques s'expriment. Chez le Pétrel des neiges, aucun effet de l'âge n'a été détecté sur la réponse immunitaire humorale, sur l'augmentation des taux d'hormone de stress pendant la réponse immunitaire, sur la croissance ou la réponse au stress des poussins, suggérant qu'il est difficile de mettre en évidence des corrélats physiologiques de la sénescence chez cette espèce longévive. Dans l’ensemble, nos résultats suggèrent que (i) les niveaux de maintenance somatique restent élevés jusque dans la fin de vie chez les oiseaux longévifs, contrairement aux espèces peu longévives ; (ii) les traits phénotypiques associés aux comportements alimentaires pourraient être des facteurs proximaux du vieillissement en conditions naturelles ; (iii) le sexe est un paramètre majeur de la détermination des patrons de variation avec l'âge en conditions naturelles
Very little is known on the deterioration of physiological and behavioural performances with age in wild animals. Given the multifaceted nature of senescence, identifying the effects of age on physiology and behaviour remains a challenging. We investigated the effects of age on a broad array of phenotypic traits in two long-lived seabirds, the Wandering Albatross Diomedea exulans (age 2–48+ years; Ile de la Possession, Southern Indian Ocean) and the Snow Petrel Pagodroma nivea (age 7–46 years; Terre Adélie, Antarctica). We studied foraging behaviour using satellite tracking and miniaturized activity loggers, and monitored reproductive performance. An array of phenotypic traits (immune function, levels of oxidative stress, antioxidant defenses, baseline hormonal levels, endocrine and cardiac stress responses) known to reflect senescence in vertebrates was also examined. In Wandering albatrosses, there was age related patterns in foraging behaviour, stress response and reproductive performance, but not in baseline physiology. There was an unexpected pattern of spatial segregation by age in the foraging areas of male albatrosses. Old males, but not females, travelled a greater distance but were less active at the sea surface, and exhibited low foraging efficiency, suggesting that foraging ability (i. E. The ability of individuals to extract energy from their environment) might play a central role in shaping ageing patterns in natural conditions. Moreover, the stress response of non-breeding males, but not breeding males, was affected by age, suggesting that age-related patterns are enhanced when individuals face ‘challenging’ conditions. In contrast, there was no detectable effect of age in females, suggesting that senescence rates are sex-specific in wild seabirds, as in humans an in laboratory model animals. In Snow Petrels, there was no detectable effect of age on PHA-induced immune response, PHA-induced hormone levels, chick growth or chick physiology, suggesting that physiological senescence is difficult to detect in this very long-lived seabird. Overall, our results highlight that age, gender, reproductive status and foraging ability interact in shaping ageing patterns in natural conditions, and suggest that long-lived seabirds maintain a high level of physiological fitness in old age, which supports the disposable soma theory