Dissertations / Theses on the topic 'South African fur seal'

Thesis (Ph. D.)--Australian National University, 2001.
Title from PDF title page (viewed May 8, 2005). Consists of reprints of thirteen published papers, some co-authored with others, plus an introductory chapter, two unpublished manuscripts, and a conclusion. Includes bibliographical references.

The Cape fur seal Arctocephalus pusillus pusillus colony at the Robberg Peninsula, Plettenberg Bay, on the south-east coast of South Africa, was driven to extirpation by indiscriminate harvesting by the late 1800s and seals only began to recolonise this site in the 1990s. This study describes the recolonisation process from 2000 to 2009, exploring within- and between-year variation in the number of seals using the site. Numbers increased over the study period from less than 300 animals to over 3 100. Year and month were important in explaining variability in seal counts, whereas sea condition, time of day and lunar phase had minimal explanatory power. Within-year variation in seal counts decreased during the study period, which may indicate an increasing proportion of resident (as opposed to transient) seals in the colony. However, the colony is currently still in a transition phase with a low ratio of breeding to non-breeding animals and low numbers of pups born on the colony (currently still < 100 per year). The influx of seals to the Robberg area may be associated with an increase in prey availability in the area. The relative protection afforded by the Nature Reserve status of the Robberg Peninsula and the existence of a Marine Protected Area adjacent to it are likely to contribute to the growth of this colony. However, human interference associated with fishing and/or ecotourism on the Peninsula may prevent the colony from developing into a breeding colony. Faecal (scat) sampling was employed to study the diet of this increasing seal population at Robberg. Species composition and size of prey were determined, temporal variation in the diet was explored, and the potential for competition between seals and the fisheries around Plettenberg Bay was investigated. Of the 445 scats collected, 90 % contained hard prey remains. These comprised of 3 127 identified otoliths representing 15 teleost prey species, 25 cephalopod beaks representing three 6 species and three feathers representing two bird species. The seals' most important prey species in terms of numerical abundance and frequency of occurrence in the diet were anchovy, sardine, horse mackerel, sand tongue-fish and shallow-water hake (in decreasing order of importance). The proportion of anchovy in the diet increased during the study period, while sardine decreased. Sardine was the only species that increased significantly in the diet during the upwelling season. Little evidence was found of direct competition between seals and linefisheries in Plettenberg Bay, both in terms of prey species composition and quantities consumed. Scat sampling in seals holds promise as a method to track long-term changes in prey species availability. The conservation and management of this colony are discussed in light of the research findings.

Bibliography: pages 168-180.
This thesis adopts an holistic approach to evaluation of the "seal problem", which encompasses the operational and biological interactions between the South African fur seal and fisheries in the Benguela Ecosystem. The operational interactions are examined using a qualitative assessment, and speculative, single-species simulation models are developed to improve understanding of seal population dynamics, present options for seal management and explore seal-fishery interactions. The models show that the probability of a seal living longer than 20 years is 14%; that the population has increased at a rate of 5.1 % p.a. since the last major census in 1983; that in 1988 there were an estimated 1.5 million seals that consumed over 2 million tons of fish; that although seal population size is usually estimated by multiplying the number of pups by a factor of 4, this factor is very variable and under different culling regimes is usually greater than 4; that historically, the mean population : pup ratio is 4.55. The most effective means of reducing the population is to cull both pups and bulls (the population decrease resulting mainly from reduced pup production caused by disturbance during bull culling). Culling pups is the least effective means of population control. Culling cows alters the population sex ratio drastically and is considered undesirable. To achieve a small or negative population growth rate, more bulls and pups need to be culled than have been taken historically. Each of the fisheries is found to be subject to operational interactions with seals, this being most severe for the purse-seine fishery. The per capita consumption of fish by seals is similar under any management regime so it is not justified to adopt a particular culling strategy to reduce overall consumption. When either seal predation or fishing mortality is reduced, the model simulates an increase in fishery yield of Cape hakes. But there is inadequate understanding of hake population dynamics at present, and depending on the interactions between species, decreased predation may result in increased or decreased fishery yields. This study shows that operational interactions are a real problem and this biases the opinion of fishermen towards seals as competitors for fish resources.

[For the Abstract, please see the PDF files below, namely "front.pdf"] CONTENTS. Chapter 1 Introduction. Chapter 2 Gross and microscopic visceral anatomy of the male Cape fur seal with reference to organ size and growth. Chapter 3 Age determination and growth in the male Cape fur seal: part one, external body. Chapter 4 Age determination and growth in the male Cape fur seal: part two, skull. Chapter 5 Age determination and growth in the male Cape fur seal: part three, baculum. Chapter 6 Suture age as an indicator of physiological age in the male Cape fur seal. Chapter 7 Sexual dimorphism in the adult Cape fur seal: standard body length and skull morphology. Chapter 8 Reproduction in the male Cape fur seal: age at puberty and annual cycle of the testis. Chapter 9 Diet and foraging behaviour of the Cape fur seal. Chapter 10(a) The Impact of the fur seal industry on the distribution and abundance of Cape fur seals. Chapter 10(b) South African Airforce wildlife rescue: Cape fur seal pups washed from Black Rocks, Algoa Bay, during heavy seas, December 1976. Chapter 11(a) Operational interactions between Cape fur seals and fisheries: part one, trawl fishing. Chapter 11(b) Operational interactions between Cape fur seals and fisheries: part two, squid jigging and line fishing. Chapter 11(c) Operational interactions between Cape fur seals and fisheries: part three, entanglement in man-made debris. Chapter 12 Concentrations of heavy metals (Cd, Cu, Pb, Ni & Zn) and organochlorine contaminants (PCBs, DDT, DDE & DDD) in the blubber of Cape fur seals. Chapter 13 Endoparasites of the Cape fur seal. Chapter 14(a) Preliminary investigations of shark predation on Cape fur seals. Chapter 14(b) Aggressive behaviour of an adult male Cape fur seal towards a great white shark Carcharodon carcharias. Chapter 15 Conclusions and future directions.

The sense of smell in marine mammals is traditionally thought to be poor. However, increasing evidence suggests that pinnipeds may use their sense of smell in a variety of behavioral contexts including communication, foraging, food selection, and reproduction. Using a food-rewarded two-choice instrumental conditioning paradigm, I assessed the ability of South African fur seals, Arctocephalus pusillus, to discriminate between 12 enantiomeric odor pairs, that is, between odorants that are identical in structure except for chirality. The fur seals significantly discriminated between eight out of the twelve odor pairs (according to p < 0.05, with carvone, dihydrocarvone, dihydrocarveol, limonene oxide, menthol, beta-citronellol, fenchone, and alpha-pinene), and failed with only four odor pairs (isopulegol, rose oxide, limonene, and camphor). No significant differences in performance were found between the animals (p > 0.05). Cross-species comparisons between the olfactory performance of the fur seals and that of other species previously tested on the same set of odor pairs lend further support to the notion that the relative size of the olfactory bulbs is not a reliable predictor of olfactory discrimination abilities. The results of the present study suggest that sense of smell may play an important and hitherto underestimated role in regulating the behavior of fur seals.

Dyer Island is thought to host one of the most abundant populations of white sharks on the planet; this is often credited to the large (55 – 60,000) Cape fur seal colony at Geyser Rock. Yet relatively little work has ever been produced from the area. This may be attributed to the harshness in its location as a study site, exposed to wind and swell from west to east which limits research periods. This study accounts for over 220 hrs of manual tracking at Dyer Island with a further 68 added from the inshore shallow areas of the bay. Sharks focused their movements and habitat use to reefs or channels that allowed access to Cape fur seals. Movement- Based Kernel Estimates (MKDE) were used to compute home range estimates for shark movements through and around the heterogeneous structures of Dyer Island and Geyser Rock. Inshore two core areas were revealed, one being the major reef system at Joubertsdam and the other at a kelp reef where the tracked shark had fed on a Cape fur seal. At Dyer Island one core area was identified in a narrow channel, ‘Shark Alley’, here a second tracked shark foraged for entire days within meters of rafting Cape fur seals. Rate of Movement (ROM) and Linearity (LI) of tracks were low during daytime and movements were focused around areas such as Shark Alley or other areas close to the seal colony before moving into deeper water or distant reefs with higher rates of ROM and LI at night. If moonlight was strong foraging would take place to the south of Geyser Rock but with higher ROM and LI than observed during the day. Foraging patterns in this study contrast studies from other sites in South Africa and home range and activity areas were comparatively much smaller than observed in Mossel Bay. It has been established that several known white sharks forage at Dyer Island and the other studied aggregation sites, such differences in foraging would suggest that they are able to adapt their foraging behaviour to suit the environment they are in; making them site specific in their foraging ecology. Both satellite and acoustic telemetry are revealing aggregation hotspots of white sharks in South Africa. It is important that such information is used to assist the recovery of the species which has been protected since 1991, yet is rarely considered in planning of coastal developments.
Dissertation (MSc)--University of Pretoria, 2012.
Zoology and Entomology
MSc
Unrestricted

Includes bibliographical references (leaves 161-202).
How predators affect the behaviour of their prey is one of the most studied subjects in behavioural ecology, with many hypothesis and models explaining how animals should behave and even more descriptive studies detailing how they do. The unification of the empirical with the theoretical, however, remains limited. The overall aim of my thesis was to address this paucity at Seal Island, South Africa, where recently quantified patterns of predation pressure by white sharks Carcharodon carcharias on Cape fur seals Arctocephalus pusillus pusillus suggested a landscape of fear particularly apposite to this.

Odor discrimination ability was tested in four female South African fur seals (Arctocephalus pusillus pusillus) using a food-rewarded two-choice instrumental conditioning paradigm. The seals’ ability to distinguish between members of homologous series of aliphatic ketones (2-butanone to 2-heptanone) and alcohols (1-butanol to 1-heptanol) was assessed. The results showed that three out of four seals successfully discriminated between all of their stimulus combinations in both classes of odorants. One seal succeeded to reach the discrimination criterion with all 2-ketones but failed with all 1-alcohols. No significant correlation between odor discrimination performance and structural similarity of the odorants in terms of differences in carbon chain length was found in either of the two chemical classes. Furthermore, it was found that the 2-ketones were significantly better discriminated than the 1-alcohols. The fact that both classes of odorants are known to be present in the natural environment of seals provides a possible explanation as to why most of the seals were able to successfully discriminate between them. The results of the present study support the notion that the sense of smell may play an important role in behavioral contexts such as social communication, foraging and reproductive behavior of fur seals.

Bibliography : leaves 59-65.
Competition for pelagic fish resources was investigated by assessing the overlap in the food base of three land-based predators: Cape gannet (Morus capensis), Cape fur seal (Arctocephalus pusillus pusillus) and humans operating via a purse-seine fishery. Multivariate analysis the diet composition of gannets and seals and the catch composition of the pelagic fishery indicated that there were three ""feeding regimes"" during the 21-year study period: (1978-1998), an anchovy-dominated regime (1978-1983), an intermediate regime (1984-1990) and a sardine-abundant regime (1991-1998). It further showed that anchovy (Engraulis capensis) and sardine (Sardinops sagax) contributed substantially to the catches of all three top predators. Analysis of size-distributions of catches showed that the three predators generally caught the same sizes of anchovy and sardine, reflecting very little resource partitioning. The analysis demonstrated stronger competition between gannets and the purse-seiners than between gannets and seats, especially during seasons of poor recruitment. Furthermore, seasonal differences in the catches of the three predators are related to the recruitment, growth and migration of the prey species. The study confirmed previous observations that gannets prefer sardine to anchovy by showing gannet exploitation of sardine in the early 19905, when anchovy was still abundant. The gannets, which are species-specific feeders, may be impacted by substantial removals of pelagic fish resources by a large seal population and a large fishery.

Assessment of trophic interactions between increasing populations of New Zealand fur seals (Arctocephalus forsteri) and fisheries in southern Australia is limited due to a lack of species specific demographic data and an understanding of the factors influencing population growth. To establish species specific demographic parameters a cross-sectional sample of New Zealand fur seal females (330) and males (100) were caught and individually-marked on Kangaroo Island, South Australia between 2000 and 2003. The seals were aged through examination of a postcanine tooth, which was removed from each animal to investigate age-specific life-history parameters. Annual formation of cementum layers was confirmed and accuracy in age estimation was determined by examination of teeth removed from individuals of known-age. Indirect methods of assessing reproductive maturity based on mammary teat characteristics indicated that females first gave birth between 4-8 years of age, with an average age at reproductive maturity of 5 years. Among reproductively mature females, age-specific reproductive rates increased rapidly between 4-7 years of age, reaching maximum rates of 70-81% between 8-13 years, and gradually decreased in older females. No females older than 22 years were recorded to pup. Age of first territory tenure in males ranged from 8-10 years. The oldest female and male were 25 and 19 years old, respectively. Post-weaning growth in females was monophasic, characterised by high growth rates in length and mass during the juvenile growth stage, followed by a gradual decline in growth rates after reproductive maturity. In contrast, growth in males was biphasic and displayed a secondary growth spurt in both length and mass, which coincided with sexual and social maturation, followed by a rapid decline in growth rates. Age-specific survival rates were high (0.823-0.953) among prime-age females (8-13 yrs of age) and declined in older females. Relative change in annual pup production was strongly correlated with reproductive rates of prime-age females and adult female survival between breeding seasons.

>Magister Scientiae - MSc
Sea anemones (Order Actinaria) are a diverse order from the Class Anthozoa. They are found in all marine habitats at all depths and their symbiotic relationships play an important role in energy transfers especially in the benthic-pelagic community. The evolutionary background and phylogenetics of the class is poorly understood due to a lack of correspondence between taxonomic and molecular data (Daly et al. 2008). Therefore, a deeper exploration into Cnidarian molecular biology is needed to establish these as an evolutionary model organism. Gene discovery from various marine invertebrates has facilitated the recovery of anti-cancer drugs, antibiotics and reporter genes (Faulkner, 2000; Allen and Jaspars, 2009). The most commercially lucrative products from sea anemones are fluorescent and chromoproteins (FP/CP), which are used as non-invasive real-time reporter genes. The applications for these proteins are extensive and range from monitoring cellular processes such as protein localisation and interactions to imaging (Alieva et al. 2008). Therefore, novel FP and CPs have potential for commercialization. The aims of the project were to analyze basic molecular diversity of the sea anemones Pseudactinia varia, Pseudactina flagellifera and Bunodosoma capensis and evaluate a new screening method to isolate novel FP and CPs. To assess the basic molecular diversity, of the sea anemones and their associated symbionts 16S rRNA and 18S rRNA clone libraries were generated. The sea anemones used in this study clustered together with those of the Family Actiniidae. The bacterial associations observed based on the closest relative BLAST analysis were dominated by Proteobacteria (gamma, alpha and epsilon) as well as Bacteroides. The associate bacterial symbionts possibly produce compounds that range from polyunsaturated fatty acids, polyhydroxyalkanoates to anti-microbial compounds that aid the host in various processes. In order to screen for FPs and CPs from sea anemones three types of cDNA libraries were generated to be screened either by sequence based or activity based approaches. Novel primers were designed which could be applied for the screening of a variety of Anthozoans. A positive control was also designed and synthesised in order to test the capability of the designed primers and optimise the amplification. Although amplicons were generated from gDNA and cDNA libraries from each of the sea anemones they were found to be non-specific products. The detection limit is likely to be the limiting factor. The construction of an activity based library was not achieved due to technical constraints, which highlights the need for new molecular tools in this field or improvements to the existing ones.
National Research Foundation (NRF)

Thesis (MMil)--Stellenbosch University, 2014.
ENGLISH ABSTRACT: Since the beginning of naval power, navies have been used by their states as instruments of foreign policy. In South Africa, the political transition since 1994 originated the evolution of the country’s foreign policy. Accordingly, foreign policy has implications for the South African Navy (SAN). Traditionally, navies have three main roles, namely: military, policing and diplomatic, roles. This study only focuses on the diplomatic role of the navy, termed naval diplomacy. In this regard, the SAN is the custodian of South African naval diplomacy. The purpose of this study is to investigate and theoretically appraise the nature and scope of South African naval diplomacy since 1994. The study has two objectives: firstly, it seeks to outline the most salient features of South Africa’s foreign policy, post-1994, as the framework for naval diplomacy; and secondly, it seeks to analyse and describe how the SAN has utilised naval diplomacy, namely: maritime coercion, naval cooperation, international maritime assistance, and international conflict resolution and management, in pursuit of South Africa’s foreign policy objectives. The research methodology is a qualitative descriptive analysis, using a literature study, factual data sources, and interviews, as techniques. Both primary and secondary sources are consulted. This study makes an original contribution to the gap in the literature on South African naval diplomacy. In this regard, with the procurement of the recent ships and submarines, South African naval diplomatic capabilities have improved significantly. It is for this reason that the SAN is currently instrumental in maritime coercion in the region, particularly deterrence against piracy and other maritime insecurity issues. The SAN is also immensely involved in naval cooperation. In terms of international maritime assistance, the SAN does not only assist other countries in search and rescue missions, but also empower them. It also plays a vital and evolving role in international conflict resolution and management. The, however, SAN faces several hindrances including ageing equipment and ships (such as strike craft and hydrographic survey vessel); lack of patrol vessels and sea lift capability; loss of skilled personnel; and other challenges.
AFRIKAANSE OPSOMMING: Sedert die ontstaan van vlootmagte het state vlote as buitelandse beleidsinstrumente aangewend. Die politieke oorgang in Suid-Afrika in 1994 het tot ʼn evolusie in die land se buitelandse beleid aanleiding gegee, wat ook gevolge vir die Suid-Afrikaanse Vloot (SAV) ingehou het. Tradisioneel het vlote drie hooffunksies, naamlik ʼn militêre, ʼn polisiëring en ʼn diplomatieke funksie. Hierdie studie fokus slegs op die diplomatieke funksie van die vloot, waarna verwys word as vlootdiplomasie, en die SAV se rol as die ‘bewaarder’ van Suid-Afrikaanse vlootdiplomasie. Die doel van hierdie studie is om ondersoek in te stel na die aard en omvang van Suid-Afrikaanse vlootdiplomasie sedert 1994 en dit aan die hand van relevante teoretiese beginsels te beoordeel. Hieruit voortspruitend is twee doelwitte: eerstens om die wesenskenmerke van Suid-Afrika se buitelandse beleid na 1994 as raamwerk vir vlootdiplomasie te gebruik; en tweedens om die wyse waarop vlootdiplomasie ter ondersteuning van Suid-Afrikaanse buitelandse beleidsdoelwitte aangewend is, te beskryf en te ontleed met spesifieke verwysing na maritieme dwang, samewerking tussen vlootmagte, internasionale maritieme hulpverlening, en internasionale konflikresolusie. Die navorsingsmetodologie is 'n kwalitatiewe beskrywende ontleding, gegrond op 'n literatuurstudie, feitlike bronne, en onderhoude. Beide primêre en sekondêre bronne is in die proses geraadpleeg. Hierdie studie is 'n oorspronklike bydrae om die leemte in die literatuur oor die Suid-Afrikaanse vlootdiplomasie aan te spreek. Na die onlangse aanskaffing van nuwe skepe en duikbote, het die SAV se diplomatieke vermoëns aansienlik verbeter. Die gevolg is dat die SAV tans ʼn wesenlike bydrae met betrekking tot maritieme dwang in die streek speel, veral wat teen-seerowery en ander maritieme veiligheidsbedreigings betref. Die SAV is ook baie betrokke in maritieme samewerking. Wat internasionale maritieme hulp betref, het die SAV ander lande met soek en reddingsoperasies bygestaan en ook bemagtig. Die SAV lewer ook ‘n groeiende bydrae tot internasionale konflikresolusie en bestuur. Maar die SAV staar ook verskeie uitdagings in die gesig wat die volgende insluit: verouderde toerusting en skepe (soos aanvalsvaartuie en die hidrografiese opmetingskip); 'n gebrek aan patrollievaartuie en 'n see-verplasingsvermoë; verlies van opgeleide personeel, en verskeie ander uitdagings.

Thesis (MA)--Stellenbosch University, 2003.
ENGLISH ABSTRACT: Saving the life of another person cannot be measured in monetary terms. It is also impossible to describe the satisfactiori of carrying out a successful rescue to anybody. However, the disappointment and sense of failure when a rescue mission fails and a life is lost, is devastating. Many rescue workers, including those of the National Sea Rescue Institute (NSRI), have experienced this overwhelming sense of failure. Rescue workers often dwell on failed rescue attempts, wishing that they could have arrived on the scene earlier or knew where to start looking for people. The fact that lives are still lost, despite the best efforts of rescue workers, points to the need to improve on life saving techniques, procedures, equipment and technology. Providing the NSRI with a workable tool to help them manage and allocate resources, plan a rescue, determine drift speed and distance or create search patterns, may one day be just enough to save one more life. With this goal in mind, a search and rescue application, called RescueView, was developed utilising ArcView 3.2a. This application was specifically designed for use by the NSRI, and it will be used as a command centre in all NRSI control rooms and for all rescue efforts.
AFRIKAANSE OPSOMMING: Om die lewe van 'n ander persoon te red, kan nie in geldwaarde gemeet word nie. Dit is ook onmoontlik om aan enige iemand die bevrediging van 'n suksesvolle redding te beskryf. Die terleurstelling en gevoel van verlies is egter baie groot wanneer 'n reddingspoging misluk en 'n lewe verloor word. Menige reddingswerkers, insluitend dié van die Nasional Seereddingsinstituut (NSRI), het al hierdie oorweldigende gevoel van mislukking ervaar. Reddingswerkers tob dikwels oor onsuksesvolle reddingspogings en wens dat hulle vroeër op die toneel aangekom het of geweet het waar om vir mense te begin soek. Die feit dat lewensverlies steeds plaasvind, ten spyte van reddingswerkers se beste pogings, dui op die behoefte om lewensreddingstegnieke, -prosedures, -toerusting en -tegnologie te verbeter. ( Deur die NSRI met 'n werkbare instrument te voorsien, wat hulle kan help om hulpbronne te bestuur en toe te wys, 'n redding te beplan, dryfspoed en -afstand te bepaal of soekpatrone te skep, mag eendag dalk net genoeg wees om nog 'n lewe te red. Met hierdie doel in gedagte is RescueView, 'n soek- en reddingsapplikasie, deur middel van ArcView 3.2a ontwikkel. Hierdie applikasie is spesifiek ontwerp vir gebruik deur die NSRI en dit sal as beheersentrurn in alle NSRI kontrolekamers en vir alle reddingspogings gebruik word.

In South Africa the need to protect and manage the national water resource has led to the development of the Reserve as a basic right under the National Water Act (1998). The Ecological Reserve relates to the quality and quantity of water necessary to protect the sustainable functioning of aquatic ecosystems. The geomorphological contribution to setting the Reserve has focussed on three groups of information requirements: the spatial and temporal availability of habitat, the maintenance of substratum characteristics, and the maintenance of channel form. This thesis focusses on the second and third information requirements. The thesis has attempted to achieve this by adding value to the theoretical and applied understanding of the magnitude and frequency of channel forming discharge for selected southern African rivers. Many of the eastern sea-board rivers are strongly influenced by bed rock in the channel perimeter, and by a highly variable hydrological regime. This has resulted in characteristic channel forms, with an active channel incised into a larger macro-channel being a common feature of eastern seaboard rivers. Within the active channel inset channel benches commonly occur. This alluvial architecture is used to provide clues as to the types of flows necessary to meet the Reserve. Three river basins are considered : the Mkomazi, Mhlathuze and Olifants. The Mkomazi is a relatively un-impacted perennial eastern-sea board river and forms the research component of the study. The Mhlathuze and Olifants rivers are highly regulated systems and form the application component of the study. Utilising synthesised daily hydrological data, bed material data, cross-sectional surveys, hydraulic data and relevant bed material transport equations, channel form was related to dominant discharge and effective discharge in an attempt to identify the magnitude and frequency offlows that can be considered to be ' effective'. Results from the Mkomazi River indicate that no single effective discharge exists, but rather that there is a range of effective discharges in the 5-0.1% range on the 1-day daily flow duration curves that are responsible for the bulk (>80%) of the bed material transport. Only large floods (termed 'reset'discharges) with average return periods of around 20 years generate sufficient stream power and shear stress to mobilise the entire bed. The macro-channel is thus maintained by the large ' reset' flood events, and the active channel is maintained both by the range of effective discharges and the ' reset 'discharges. These are the geomorphologically 'effective' flows. Results from the Mhlathuze River have indicated that the Goedertrouw Dam has had a considerable impact on the downstream channel morphology and bed material transport capacity and consequently the effective and dominant discharges. It has been suggested that the Mhlathuze River is now adjusting its channel geometry in sympathy with the regulated flow environment. Under present-day conditions it has been demonstrated that the total bed material load has been reduced by up to three times, but there has also been a clear change in the way in which the load has been distributed around the duration curve. Under present-day conditions, over 90% of the total bed material load is transported by the top 5% of the flows, whereas under virgin flow conditions 90% of the total bed material load was transported by the top 20% of the flows. For the Olifants River there appears to be no relationship between the estimated bankfull discharge and any hydrological statistic. The effective discharge flow class is in the 5-0.01% range on the 1-day daily flow duration curve. It has also been pointed out that even the highest flows simulated for the Olifants River do not generate sufficient energy to mobilise the entire bed. It is useful to consider the Olifants River as being adapted to a highly variable flow regime. It is erroneous to think of one ' effective' discharge, but rather a range of effective discharges are of significance. It has been argued that strong bed rock control and a highly variable flow regime in many southern African rivers accounts for the channel architecture, and that there is a need to develop an ' indigenous knowledge' in the management of southern African fluvial systems

Thesis (MBA)--Stellenbosch University, 1998.
ENGLISH ABASTRACT: The techniques for animal reproduction and husbandry for both abalone and sea turtle farming have been well established and researched over the last decade. Although market related data seems to be scarce, marketing analysis reviewed and conducted as part of this study suggests that extensive markets exist for live cocktail size abalone and sea turtle products, especially in the East Asian countries. A decline in natural resources and increased demand resulted in a fast expanding niche market for these products. This study shows that development of an abalone farm in South Africa for the production of cocktail size (±80 mm; ±100 g) is a highly profitable venture. Economic feasibility analysis indicated that the development of an abalone farm capable of producing 150 tons annually should result in a rate of return in excess of 50% over a seven-year investment period. On the other hand, sea turtle farming is a less profitable investment with Green turtle farming yielding a return of approximately 25% and Hawksbill farming yielding a return closer to 30% over a seven-year investment period. According to the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES), all sea turtle species have been listed as endangered or threatened. Currently all countries who are members of CITES are prohibited from international trade in sea turtles or sea turtle products. Prospective entrepreneurs wishing to establish a sea turtle farming venture have to adhere to stringent regulatory and control measures, a major obstacle in the development of a profitable enterprise. Both abalone and sea turtle farming have long payback periods, due to the slow growth-rates of the investigated species. In order to produce animals in a time frame that is economically viable, artificially formulated feeds have to be used. The usage of artificially formulated feeds proved to be a major expense, especially in the case of sea turtle farming.
AFRIKAANSE OPSOMMING: Die tegnieke vir die reproduksie, onderhoud en groei van beide perlemoen en seeskilpad akwakultuur boerderye is goed gevestig en nagevors oor die afgelope dekade. Alhoewel mark verwante data skaars is, dui bemarking analises aan dat 'n enorme mark bestaan vir lewendige "cocktail" grootte perlemoen en seeskilpadprodukte, veral in Oos Asie. 'n Afname in natuurlike hulpbronne en 'n toename in aanvraag, het 'n vinnige "nis" mark vir die produkte tot gevolg gehad. Die ontwikkeling van 'n perlemoen boerdery vir die produksie van "cocktail" grootte (±80 mm; ±100 g) perlemoen kom voor as 'n hoogs winsgewende onderneming. 'n Ekonomiese winsgewindheidsanalise het getoon dat die ontwikkeling van 'n perlemoenplaas, met 'n produksie van sowat 150 ton perlemoen jaarliks, 'n opbrengs van oor die 50% oor 'n sewe jaar investeringsperiode teweeg sal bring. Seeskilpad boerdery, aan die ander kant, kom as 'n minder winsgewende belegging voor, waar Groen seeskilpad boerdery 'n opbrengs van ongeveer 25% en Hawksbill boerdery 'n opbrengs van min of meer 30% oor 'n sewe jaar beleggings periode toon. Volgens CITES (Convention on International Trade in Endangered Species of Wild Fauna and Flora) is alle seeskilpaaie gelys as bedreig. Alle lande wat huidiglik lede is van CITES, word van die reg voorbehou om internasionale handel te dryf in seeskilpaaie of seeskilpadprodulcte. Voorgenome entrepeneurs met die begeerte om 'n seeskilpadboerdery te begin, sal voor streng maatreels en beheer- maatstawwe te staan kom, wat 'n groot stuikelblok is in die ontwikkeling van 'n winsgewende seeskilpadplaas. Beide perlemoen- en seeskilpadboerderye het lang terugbetalingsperiodes, 'n waameming wat verduidelik kan word aan hand van die stadige groei-tempo's van die bestudeerde spesies. In orde om diere in 'n spesifieke tydsperiode te produseer wat ekonomies winsgewend is, moet daar van artifisieel geformuleerde voeding gebruik gemaak word. Die gebruik van geformuleerde voeding. is egter duur, veral in die geval van seeskilpadboerderye.

O lobo-marinho-sul-americano (Arctocephalus australis) membro da Ordem Carnivora, é comumente visto nos períodos de outono e inverno na costa brasileira do Rio Grande do Sul até o Rio de Janeiro, porém, sem colônias reprodutivas estabelecidas. A espécie pertence ao grupo dos pinípedes, carnívoros com membros em forma de nadadeiras que vivem em ambiente aquático e terrestre. Estudos sobre a morfologia da pele em pinípedes são raros e antigos, destes procederam muitos relatos divergentes, em virtude da colheita da pele sem referências anatômicas. O objetivo desta pesquisa foi descrever o sistema tegumentar da espécie Arctocephalus australis, utilizando animais que vieram a óbito por causas naturais de uma colônia reprodutiva do Uruguai. As áreas corporais colhidas dorso-ventralmente foram identificadas anatomicamente. Essas regiões foram examinadas por microscopia óptica, segundo critérios histológicos, histomorfométricos, histoquímicos e imuno-histoquímicos nas diferentes estruturas que constituem o sistema tegumentar. A pele do Arctocephalus australis apresentou diferenças entre as regiões de epiderme delgada e espessa. A epiderme delgada apresentou maior quantidade de pêlos do que a epiderme espessa, a qual em algumas regiões era destituída destes. Como os demais mamíferos, a pele do lobo-marinho-sul-americano apresentou glândulas sebáceas, glândulas sudoríparas apócrinas e merócrinas. As nadadeiras apresentaram o maior número de especializações entre as regiões do corpo estudadas, especialmente vinculadas à termorregulação, como o maior volume de glândulas sudoríparas e secções vasculares. Esta pesquisa apontou os aspectos morfofuncionais relacionados à biologia da espécie em ambientes distintos, e esclareceu alguns dados controversos na literatura sobre o sistema tegumentar em pinípedes.
The South American fur seal (Arctocephalus australis) members of the Order Carnivora is usually seen during the autumn and winter season in the Brazilian coast from Rio Grande do Sul to Rio de Janeiro, however, there are no reports of reproductive colonies established. The species belongs to the group of pinnipeds, carnivorous with limbs fin-shaped that inhabits both terrestrial and aquatic environments. Studies of the skin morphology are rare and ancient; these studies have arisen many divergent reports, due to sampling of the skin without anatomical references. The purpose of this research was to describe the integumentary system of the species Arctocephalus australis, using animals that came to death by natural cases from reproductive colonies from Uruguay. The body dorsal and ventral regions were identified anatomically. These regions were examined by light microscopy, according to the histological, histomophometric, histochemical and immunohistochemical criteria in the different structures constituting the integumentary system. The skin of the Arctocephalus australis showed differences between the thin and thick epidermis. The thin epidermis showed larger amount of hair follicles than the thicker epidermis, which in some regions was devoid of hair. As well as the other mammals, the South-american-fur-seal skin showed sebaceous glands, apocrine and eccrine sweat glands. The limbs showed the largest number of the specialization among the regions of the body examined, particularly related to thermoregulation, as well as the largest volume fraction of sweat glands and vascular sections. This research pointed the morphofunctional aspects related to biology of the species in different environments, and elucidated some controversial data in the investigation about the integumentary system in pinnipeds.

Predators and the risk associated with their presence may affect group composition, group size, movement patterns, and habitat use of prey species. The removal of predators, or their reintroduction following long periods of absence, equally can have profound impacts on their prey, triggering ecological cascades and ultimately shaping the biota of entire landscapes. While such processes are well documented in terrestrial ecosystems, similar results are absent in the marine realm, largely due to logistical difficulty. One exception to this is the study of white shark and seal interactions at coastal island rookeries, where white shark presence is seasonal, and seals exhibit marked behavioural differences between seasons. What is lacking from these studies, however, is how subsurface habitat around the islands, specifically refugia, may influence the behaviour of seals and their interactions with white sharks. I address this challenge by comparing both seal movement patterns and shark-seal interactions at Geyser Rock, Gansbaai with the established seal and shark patterns at Seal Island, False Bay. White sharks aggregate at both islands during the austral winter and seals encounter these aggregations when commuting to and from their respective rookeries to offshore foraging areas. The seascape around Geyser Rock is comparably more featured, including kelp beds and extensive shallow (5-10m depth) reef systems, whereas Seal Island is largely featureless, with neither extensive kelp nor reefs. At Geyser Rock, predations by white sharks were rarely observed (0.1 predations/hour) compared to Seal Island (1.24 predations/hour) and lacked the focused spatiotemporal peak at sunrise to the south of the island. Seals at Geyser Rock did not show a relationship between group formation and season, which was clearly demonstrated at Seal Island. This suggests that seals at Geyser Rock may be less reliant on group formation (safety in numbers) and selfish herd tactics within such groups to reduce predation risk. Rather, seals at Geyser Rock avoided deep open water patches during winter and shifted their movement patterns to and from the island to sectors with greater subsurface habitat heterogeneity. While I was limited in quantifying spatiotemporal patterns of predation risk around Geyser Rock (predation events were rare and widely dispersed), these results strongly suggest that seals actively avoid deep open water and show a preference for high structural complexity sectors during the risky winter months when shark presence is highest. This finding represents a habitat-escape tactic unidentified in previously studied white shark/pinniped systems. Together these results provide empirical support for both the risk-allocation hypothesis and refugia hypotheses within marine predator-prey systems.

The Knysna seahorse Hippocampus capensis is South Africa’s only endemic seahorse species, and is found in only three adjacent estuaries along the southern coast. The conservation of this endangered species is important on a national and international level. This study presents the first research on this species within the Knysna estuary since 2001 and specifically focuses on aspects of its ecology within a residential marina estate (Thesen Islands Marina). The physico-chemical and habitat features of the marina were described and the population ecology, habitat use, and behaviour of the Knysna seahorse were investigated. Physico-chemical conditions within the western section of the marina, characterised by high water current velocities, were similar to that of the adjacent estuary. The eastern section of the marina was characterised by lower water current velocities and higher turbidity. Four major habitat types were identified within the marina canals: (I) artificial Reno mattress (wire baskets filled with rocks); (II) Codium tenue beds; (III) mixed vegetation on sediment; and (IV) barren canal floor. Seahorse densities within the marina were significantly higher compared to densities found historically within the estuary. Highest seahorse densities were specifically found within the artificial Reno mattress structures and within the western section of the marina. Seahorse density varied spatially and temporally and the type of habitat was an important predictor for seahorse occurrence. An experimental investigation found that H. capensis chooses artificial Reno mattress habitat over Zostera capensis when given a choice. GoPro cameras were used successfully to investigate daytime seahorse behaviour within the Reno mattress habitat. Seahorses were more active during the morning, spent most of their time (> 80 %) feeding, and morning courting behaviour for this species were confirmed. However, during the summer holiday period (mid-December to mid-January) few seahorses were observed on camera, which suggests that the increase in motor boat activity and the related increase in noise had a negative effect on H. capensis feeding and courting behaviour. The marina development, and in particular the Reno mattresses, created a new habitat for this endangered species within the Knysna estuary. In addition to the protection and restoration of natural habitats in which H. capensis is found, the conservation potential of artificial structures such as Reno mattresses should be realised.

Environmental fluctuations in the eastern Pacific Ocean are reflected in the tissues of some of its most vulnerable apex predators, the Peruvian fur seal (PFS) Arctocephalus australis ssp.and the South American sea lion (SASL) Otaria byronia.These large pinnipeds live in sympatry along the Pacific coastline of South America and forage within the neritic waters over the continental shelf. The coastal waters off Peru are a region of great environmental fluctuations due to periodic, oscillating El Niño- La Niña- Southern Oscillation (ENSO) events, which result in ecosystem-wide food web changes. Pinniped vibrissae (whiskers) are continuously growing keratinous tissues and reflect the incorporation of prey from the region. Fine resolution sampling along their length provided trophic information on a weekly to monthly time scale over several years. Vibrissae were obtained from 2010-2016 from female (n=47), male (n=17) and newborn pup (n=6) fur seals and male (n=6) sea lions collected during pinniped rookery health assessments. Stable isotope ratios (δ13C and δ15N) in vibrissae infer temporal primary production and dietary variations in individuals. ENSO conditions were dictated by the sea surface temperature anomaly (SSTA) recordings from the Niño 1+2 Index region over 12 years. Fluctuations in vibrissae δ15N were correlated to varying SSTA readings (p15N (p15N signatures (p13C revealed minor fluctuations ranging from -18.13 to -13.17‰over the 12-year period, δ13C did reveal a significant depletion and enrichment oscillation during specific points in time, such as the 2014-2016 El Niño event, which ranged from -15.09 to -13.83‰(p=0.040). Stable isotope signatures varied between genders, but not by species. Female fur seal stable isotope signatures were significantly more depleted in both δ13C and δ15N than males (p13C and δ15N were inversely correlated to each other from 2014 to 2016; this was during the strongest El Nino-Southern Oscillation event on record (p=0.002). As δ13Csignatures became more enriched, δ15N signatures depleted from 2014 until 2016. This suggests that when ENSO warm phase conditions occur, the environments resources change in historic foraging grounds, possibly forcing pinnipeds to travel farther distances offshoreto forage or altering what they feed on throughout these stressful conditions.This study serves to help understand of the impact of oceanographic influences on these pinnipeds.ENSO conditions influence the trophic dynamics and resultant survival adaptations in both of these vulnerable Peruvian marine mammals.

Sea urchin aquaculture for human food is a major industry, and there are prospects for the industry in South Africa. Feeding preferences of the sea urchin Tripneustes gratilla were tested by two different methods; a touch-preference test and a 48-hour consumption test. A touchpreference is established when the sea urchins' lantern teeth touched an algal species. The 48-hour consumption test was performed with paired combinations using four species of fresh algae. It was hypothesized that the preferred species would be similar in the touch-preference test and the consumption test. Five algal species were used in the touch-preference test; namely, Ecklonia maxima (kelp), Gigartina polycarpa, Grateloupia capensi, Porphyra capensis, and U/va rigida. Four of these species were used in the paired consumption test; namely, E. maxima, G. polycarpa, P. capensis and U. rigida. We found that E. maxima was most preferred in the touch-test followed by P. capensis and U. rigida. This result did not correlate with our consumption test. Here, U. rigida was significantly most preferred followed by E. maxima. Overall, the result is significant in relation to the prospect of echinoculture in South Africa as Ulva may provide a valuable alternate feed or supplement to this new industry. Due to the increase in time provided for the paired consumption test, we found that the paired consumption test was more conclusive in providing a preference for Tripneustes gratilla. Our results agree with literature which suggests that Tripneustes gratilla is a genera list feeder; however, Tripneustes gratilla shows definite preferences. Ulva spp. has been grown on a number of abalone farms in South Africa. Integrated aquaculture using T. gratilla and U. rigida as a biofilter and alternate feed is a very promising idea for echinoculture in South Africa.

The thesis investigates the development of short-sea shipping (SSS) in the Southern African Development Community (SADC) region by studying the determinants of SSS, the stated choice preference of shippers and freight forwarders and the stated intentions of maritime carriers for SSS. It is purported the introduction of SSS in SADC could reduce socio-environmental problems currently faced such as road damage, road congestion, pollution and transport related accidents. Discrete choice modeling (DCM) is employed as the main methodology to study shipper and carrier behavior. Discrete choice modeling permits the construction of general utility functions incorporating various decision maker characteristics and choice attributes to elicit preference of respondents. The general postulate in DCM is that utility is derived from the properties of things rather than the actual thing per se. A particular benefit of DCM in this study is the elicitation of preference for services and interventions that have not been introduced by SSS. The first step in the study is a theoretical investigation of the potential of SSS in the SADC region. It highlights the policy initiatives, the barriers and enablers related to the development of SSS. The proposed SSS system would have three main roles: to offer an alternative mode of freight transport service between port cities, to serve as the main leg in an intermodal transport network, and to serve feeder services between hub-and-spoke ports. The findings reveal that, SSS has the theoretical potential to work in the SADC region, given the large geographic region, projected freight volumes and customs and trade policies the SADC region is pursuing. The second step in the study involves an a-priori study conducted to develop a general understanding of freight transport in SADC. For this purpose, a uniquely developed online survey was conducted across the SADC region to ascertain in particular: who the decision maker is in terms of freight mode choice; and what the significant attributes that influence freight mode choice are. The results reveal that both the shipper and the freight forwarder are involved in mode choice decisions, however the shipper being the dominant decision maker. Furthermore, the results of the exploded logit model reveal that the top five modal attributes that shippers consider most important are: reliability, transport cost, risk of damage, frequency of service and transit time. These results were subsequently employed to inform the shipper and carrier behavior studies. The third step entails the assessment of shipper behavior, where trip specific mode choice decisions are studied along five intra-urban origin-destination (O-D) paired routes (which would form the study corridors). Three of these corridors considered unimodal SSS, and the two considered intermodal SSS. Unimodal SSS was studied along the following corridors: Cape Town (South Africa)~ Walvis Bay (Namibia), Walvis Bay (Namibia) ~ Luanda (Angola) and Durban (South Africa) ~Beira (Mozambique); and intermodal SSS was studied along the following corridors: Durban (South Africa) ~ Harare (Zimbabwe) and Cape Town (South Africa) ~ Windhoek (Namibia). To develop the choice scenarios, d-efficient stated choice experiments were uniquely developed for each of the corridors with the following key modal attributes systematically varied and analyzed across respondents: service frequency, reliability in terms of arriving on time, expected delay, transport cost and transport time. Subsequently, the following choice models were developed: Binary Logit, Mixed Logit and Integrated Choice and Latent Variable Structure models for the unimodal corridors; and Multinomial Logit, Nested Logit and Cross Nested Logit models for the intermodal corridors. The results highlight that in addition to the modal attributes, mode choice decisions are driven by shipper characteristics and situational characteristics. Moreover, the unimodal SSS study reveals that underlying latent perceptions also influence freight mode choice decisions; while the intermodal SSS study reveal strong correlations in the intermodal SSS alternatives, which requires improved intermodal capability if SSS is to become competitive. The fourth step in the study entail the assessment of maritime carriers preference for SSS given varying levels of maritime conditions that include: dedicated freight volumes, income from freight, port dues discount, terminal handling fees discount and ship registration requirements. The results of an ordered logit model reveal that ship registration provisions and terminal handling charges are the most important to the development of SSS from a carrier side. Moreover, ship registration and maritime cabotage provisions require visitation to boost the participation of carriers in SSS. The last step of the study revisits the modeling results and considers their implications through the estimation of willingness-to-pay and attribute elasticities. The results were then employed to suggest policy actions and interventions to develop SSS.

Thesis (MScEng)--Stellenbosch University, 2012.
ENGLISH ABSTRACT: Chip and spray surfacing seals has been widely used in South Africa as the preferred surface treatment for rural roads. The design of these seals has also experienced renewed interest and continuous development in several other countries over the past two decades. In South Africa seals are continually used as increasing attention is given to the periodic maintenance of existing surfaced roads. There is also a significant increase in the use of surfacing seals in North America as the need to develop more energy and resource efficient surfacing options becomes a priority. Despite this growing use of surface seals, the seal design and especially the selection of binder type and grade does not always follow scientific processes. Seals are often designed based on client preference, previous experience, material availability and industry trends. With an ageing road network and limited funding to ensure timeous maintenance, the focus in South Africa is moving towards more stringent and scientific design processes. The USA and Europe, forced by increasing traffic volumes and heightened performance demands, are moving towards performance- based specification to account for deficiencies in their current surface seal design methods. One of the major failure mechanisms of surface seals is ravelling which takes place when the binder and the aggregate bond becomes weak and are broken by the forces generated by traffic. This leads to loose aggregate on the road which in turns leads to bare surface patches and broken windscreens. To prevent and address this as part of the development of performance-based specifications, the need for a simple and inexpensive technique for evaluating bitumen and bitumen emulsion bond strength development over time, as well as binder-aggregate compatibility, was identified. Although various tests exist for investigating adhesion between bituminous emulsions and aggregate chips most of the tests does not deliver the level of information required by the performance-based specifications. The Bitumen Bond Strength (BBS) test method was therefore developed with the aim to address some of the limitations encountered in evaluating bond strength between binders and aggregates. The BBS test (AASHTO TP-91, 2011) was developed by the University of Wisconsin – Madison (UWM) in partnership with the University of Ancona – Italy (UAI) and the University of Stellenbosch – South Africa (US) specifically for evaluating bond strength between aggregates and hot applied binders and emulsions, respectively. US became involved in BBS test efforts in 2008 to assist in the development and practical evaluation of the BBS test method. UAI contributed significantly to the development of the test apparatus through their work in conjunction with UWM. Due to time and resources available, the involvement of the US was limited to various discussion sessions, a study tour, the evaluation of the BBS test, and conducting a series of control tests. By using the Bitumen Bond Strength test it was possible to evaluate the practicality and repeatability of the developed procedure and the results measured was successfully used to evaluate the bond strength development of modified and unmodified bitumen emulsions on tillite and granite aggregates. It was also possible to correlate the results achieved at the University of Stellenbosch with results from the University of Wisconsin-Madison due to the fact that testing took place at both institutions. The development of the test and the inter-laboratory test results in essence reinforced the hypothesis that the BBS test protocol can be used to effectively evaluate bond strength of different emulsion types and aggregate types. Except for the loading rate which is a known critical influence, the emulsion type and curing intervals are both identified as the most significant other factors contributing to bond strength development. Aggregate type is also identified as a significant factor that will influence the bond strength development. Interactions between emulsion type and curing interval are identified as the most significant interaction. A lot of further validation test on the BBS test method is still required for the test to be integrated into a performance-based specification system for surface seals.
AFRIKAANSE OPSOMMING: “Chip and Spray” oppervlak seëls is die verkose seël tipe vir gebruik op Suid Afrikaanse plattelandse paaie. Die ontwerp van hierdie tipe seëls is ook tans besig om hernude aandag te trek in heelwat lande. In Suid Afrika word die tipe seël al meer gebruik soos die behoefte na herseël projeke op die verouderde pad netwerk groei . Daar is ook heelwat groei in die gebruik van “Chip en Spray” seëls in Noord Amerika aangesien daar n behoefte is om n meer energie en materiaal effektiewe seëls te gebruik. Ten spyte van die groeiende gebruik van hierdie seëls het daar min wetenskaplike ontwikkeling plaasgevind in the ontwerp daarvan. Seëls word meestal ontwerp gebaseer op klient voorkeur , ondervinding, materiaal beskikbaarheid en ook industrie norms. ‘n Verouderde pad netwerk dwing die Suid Afrikaanse industrie om meer deeglike en wetenskaplike ontwerp prosedures te volg. Die VSA en Europa word deur vinnig groeiende verkeersvolumes en verhoogte kwaliteits behoeftes gedwing om prestasie gebaseerde spesifikasies te ontwikkel. Een van die hoof defekte op seëls is klipverlies wat plaasvind as die verbinding tussen die bitumen en aggregaat verswak en gebreek word deur die kragte wat deur verkeer oorgedra word. Dit lei tot los klip op die pad wat weer tot skade aan voertuie lei. Om dit te voorkom en aan te spreek het die behoefte laat ontwikkel vir n maklike en goedkoop tegniek om te meet hoe sterk die verbinding is wat ontwikkel tussen verskillende bitumen, bitumen emulsies en aggregaat monsters. Alhoewel daar alreeds toetse bestaan wat kan toets hoe sterk die verbinding is , gee die meeste van die toetse nie die informasie wat benodig word deur die voorgestelde prestasie gedrewe spesfikasies nie. Die “Bitumen Bond Strength” (BBS) toets metode is daarom ontwikkel om die tekortkoming in die toets van die bitumen en aggregaat verdindinge aan te spreek. Die BBS toets (AASHTO TP-91, 2011) is ontwikkel by die Universiteit van Wisconsin – Madison (UWM) in vennootskap met die Universiteit van Ancona – Italy (UAI) en die Universiteit van Stellenbosch (US) , spesifiek om die die sterkte van die verbinding wat vorm tussen aggregaat en bitumen te meet. Die US het in 2008 betrokke geraak by die BBS toets studie om hulp te verleen met die ontwikkeling en praktiese evalueering van die BBS toets metode. As gevolg van tyd en personeel tekorte is die betrokkendheid by die US beperk tot verskeie besprekings sessies, n studie toer, die evalueering van die BBS toets sowel as die voltooing van n uitgebreide stel toetse. Deur die voltooing van eksperimente met die BBS toets was dit moontlik om die uitvoerbaarheid en herhaalbaarheid van die ontwikkelde prosedure te toets. Die resultate van die toetse is suksesvol gebruik om die ontwikkeling van die verbinding sterkte tussen gemodifiseerde en ongemodifiseerde bitumen emulsies en tilliet en graniet te definïeer en te evalueer. Dit was ook moontlik om die resultate van die Universiteit Stellenbosch en die Universiteit of Wisconsin-Madison suksesvol met mekaar te vergelyk aangesien toetse by beide die instansies voltooi is. Die ontwikkeling van die toets en die inter laboratorium toets resultate het dit moontlik gemaak om die hipotese te bevestig dat die BBS toets prosedure effektief gebruik kan word om die bitumen en aggregaat verdindinge te toets en te evalueer. Behalwe vir die tempo van die lading waarteen die aftrek sterkte getoets word , is die emulsie tipe en die nabehandeling tydperk beide geidentifiseer as die mees beduidende invloede wat bydrae tot die ontwikkeling van die verbinding sterkte. Die aggregaat tipe is ook geidentifiseer as n belangrike faktor wat die verbinding sterkte ontwikkeling sal beïnvloed. Die interaksie tussen die emulsie tipe en nabehandeling tydperk was geïdentifiseer as die mees beduidende interaksie. Daar sal wel nog heelwat eksperimente voltooi moet word met die BBS toets prosedure voordat dit volkome geïntegreer kan word as deel van n prestasie gebaseerde spesifikasie stelsel vir die ontwerp van seëls.

This research project investigated the impact of predation by the Cape fur seals Arctocephalus pusillus pusillus on the conservation status of seabirds at islands off the coast of South Africa and at the Prince Edward Islands. At Malgas Island, the impact of predation was investigated over three breeding seasons (2000/01, 2003/04 and 2005/06), and at Dyer Island over two breeding season (2004 and 2006/07). At Marion Island (Prince Edwards Islands) and at other South African islands, such as Dassen Island, Bird Island at Lambertâs Bay and Robben Island, observations were collected opportunistically. Cape fur seals were estimated to have killed some 6 000 Cape gannet Morus capensis fledglings around Malgas Island in the 2000/01 breeding season, 11 000 in 2003/04 and 10 000 in 2005/06. This amounted to an estimated 29%, 83% and 57% of the overall production of fledglings at the island in these breeding seasons respectively. Preliminary modelling suggests this predation is not sustainable. There was a 25% reduction in the size of the colony, the second largest of only six extant Cape gannet colonies, between 2001/02 and 2005/06. At Dyer Island, it was estimated that seals killed up to 7% of African penguin Spheniscus demersus adults annually. The present mortality attributable to seals is considered unsustainable. Seals also killed a substantial proportion, 4â8%, of Cape cormorant Phalacrocorax capensis fledglings as they left the island. Although this level of mortality may be sustainable for Cape cormorants, this species have also been affected by disease. iv Predation on seabirds by Cape fur seals was demonstrated to occur at several other localities in southern Africa but observations were insufficient to enable the effect of such predation to be quantified. Several hundred Cape gannet fledglings were killed annually at Bird Island (Lambertâs Bay) and threatened penguins and cormorants were attacked at other localities. At subantarctic Marion Island, Antarctic fur seals A. gazella fed on king Aptenodytes patagonicus and macaroni Eudyptes chrysolophus penguins. However, predation there on seabirds by subantarctic fur seals A. tropicalis has not yet been observed. King penguins were mostly killed in winter and macaroni penguins (which are absent from the island in winter) in summer. Predation of seabirds by seals has recently increased in southern Africa and may be doing so at Marion Island. In both regions fur seal populations are expanding. The influences of environmental factors on the rate of predation were investigated at both Malgas and Dyer Islands. Of environmental factors considered, time of the day had the most important influence on predation by Cape fur seals on fledglings of Cape gannets and Cape cormorants and adult African penguins. Fledglings of gannets and cormorants were mainly killed between mid morning and late afternoon, coinciding with the time they left the islands and were in the water. Most adult African penguins were killed as they returned in the evening from foraging at sea. Wind speed and direction, sea state and tide had a variable and lesser influence on predation rates. Although these variables might be used to interpolate predation rates through periods when observations are not conducted, their contribution is limited and there will remain considerable uncertainty in the estimate of actual numbers of fledglings killed. Uncertainty will best be decreased by extending the period of observations so as to reduce the amount of days for which predation rates are interpolated. v In six years between 1999 and 2008, 141 Cape fur seals that were feeding on, or thought to be feeding on, Cape gannet fledglings as they left Malgas Island, South Africa, were shot and collected. Examination of the stomachs of 93 of these seals showed that Cape gannets contributed an average of 70% by mass to the diet, and known prey items of Cape gannets, which may have been obtained from the alimentary tract of the fledglings, a further 5%. Hence, when the seals were culled, they were subsisting mainly on the fledglings. Other prey items of the seals included rock lobster Jasus lalandii and common octopus Octopus vulgaris. All the collected seals were bulls. Their ages were estimated from measures of their total length and previously published information on ages at length. All were 10 years old or less, and their mean age was 4.5 years. The hunting behaviour of Cape fur seals feeding on seabirds at Malgas and Dyer Islands was investigated in 2003/04 and 2005/06; and 2004 and 2006/07 respectively. At these islands, attacks on seabirds were identified mainly through the presence of other birds overhead and sometimes by the thrashing of a victim in, or throwing of it from, the water. Most attacks occurred beyond the surf zone at distances of 20â100 m from the island. Seals hunted in groups or solitarily and usually attacked birds from underneath or behind. Usually most, or a substantial portion of the carcass was utilized but some surplus killing was observed. On average, attacks lasted 11 min for both Cape gannets and Cape cormorants and 16 min for African penguins. Due to the increase in seal predation, interventive management such as culling individual fur seals seen preying on seabirds was implemented at Malgas Island. It was anticipated that removal of the small number of individual seals which target seabirds would reduce vi mortality on the seabirds because this is a learned behaviour. In the 2006â07 breeding season of Cape gannets at Malgas Island, the removal of 61 Cape fur seals that preyed on gannet fledglings when they left to sea significantly reduced the mortality rate of these fledglings in the short term. However, because seals learned to avoid the boat used for their removal, it was not possible to remove all the seals that killed gannet fledglings and some mortality continued. There was a decrease over time in both the maximum and the mean age of seals culled. Sustained removal of these animals may reduce this feeding behaviour.

Thesis (MScEng)--Stellenbosch University, 2014.
ENGLISH ABSTRACT: As the world finds itself increasingly unable to avoid the negative impacts of the physical phenomena associated with climate change, adaptation to climate change has been brought to the forefront of the international agenda. The range of adaptation technologies available can be categorized into three basic strategies (IPCC, 1990): Protection, (managed) Retreat, or Accommodation. The practice of adapting existing developments and infrastructure in the coastal zone by the process of accommodation has not yet seen wide implementation as a formalised adaptation strategy. In order for a community to accept and successfully implement accommodation strategies, all community stakeholders are required to accept and live with a certain level of managed risk, and to also rethink the concept of failure. As a result, accommodation practices implemented globally have been closely related to fields such as risk - and disaster management. Structural innovations in the field of accommodation measures include advanced technologies to elevate existing buildings safely above flood levels, and even “amphibious” houses. In Cape Town, South Africa, the choice between protection, retreat or accommodation as an adaptation measure remains complex. Not much discussion has yet been generated concerning accommodation measures that could be implemented to reduce the risk to existing properties that are already inappropriately located in the risk zone (e.g. seaward of the coastal hazard line), by accommodating the dynamic coastal processes taking place. Accommodation has been found to be most feasible in Cape Town at case study sites with a stable, non- or slowly eroding shoreline, which are also subject to flooding. The elevation of buildings and the alteration of buildings for flood-proofing, in unison with proactive risk and disaster management, could be implemented to accommodate the impacts of flooding on affected infrastructure. Located on Cape Town’s Atlantic Seaboard, Bakoven serves as a case study sample of such a site where an accommodation-based adaptation solution could be feasible. Both global and regional downscaled climate models have been found to deliver a large range of future climate conditions. Assuming best estimate future predictions, Bakoven properties have been found vulnerable to extreme flooding during both status quo and future extreme events. Environmental conditions at Bakoven are favourable for the construction of piled foundations. Stringent environmental and heritage constraints imposed by local government would, however, render accommodation strategies unviable. It is recommended that government at all levels be willing to adopt a more flexible approach to governing coastal areas, to ensure that the regulations they impose remain as dynamic as the environments which they govern. The viability and possible benefits of accommodation measures, rather than protection or retreat approaches should be carefully considered on an individual case-by-case basis, in unison with the local community.
AFRIKAANSE OPSOMMING: Wêreldwyd is gemeenskappe besig om toenemend te ervaar dat hul nie die nadelige gevolge van klimaatsverandering kan vryspring nie. Juis daarom, is aanpassing tot klimaatsverandering noodsaaklik. Die verskeidenheid van beskikbare benaderinge tot klimaatsverandering aanpassing kan in drie hoof kategorieë ingedeel word, volgens die IPCC (1990): Beskerming, (stelselmatige) Retireer of Akkomodasie. Die aanpassing van bestaande infrastruktuur d.m.v. akkomodasie is nog nie wyd geïmplementeer as ‘n amptelike aanpassings strategie nie. Ten einde die sukses van ‘n akkommodasie strategie te verseker, sal gemeenskappe genoodsaak wees om ‘n sekere vlak van residuele risiko te aanvaar en die konsep van die ‘faling’ te herdefinieer. Akkommodasie oplossings wêreldwyd is daarom nouliks verwant aan risiko- en rampsbestuur. Innovasies in die struktuurindustrie om die risiko van klimaatsverandering te akkommodeer, sluit onder andere in die fisiese oplig van geboue na ‘n hoër, veilige vlak, en ook die bou van sogenaamde “amfibiese” huise. In Kaapstad is die bepaling van die mees gepaste en voordelige aanpassings oplossing, net soos in die res van die wêreld, kompleks. Die moontlikheid van die gebruik van akkommodasie benaderinge en tegnologieë, eerder as beskermingsstrategieë, is nog nie welbekend of algemeen geïmplementeer nie. Daar bestaan wel ‘n geleentheid om hierdie tegnologieë toe te pas in die geval van bestaande strukture wat seewaarts van die dinamiese kusproses lyn, geleë is. Hierdie studie het bevind dat akkommodasie oplossings moontlik suksesvol kan wees by spesifieke gevallestudies langs Kaapstad se kuslyn waar die kuslyn grootendeels stabiel is. Die oplig en verandering van geboue om vloedbestand te wees, tesame met proaktiewe risiko- en rampsbestuur maatreëls, word by sommige van hierdie gevallestudies aanbeveel om die impak van klimaatsverandering te akkomodeer. Bakoven, ‘n klein gemeenskapsbuurt op Kaapstad se kuslyn, is ‘n voorbeeld van ‘n geval waar ‘n akkommodasie oplossing moontlik goed kan werk. Globale klimaatsmodelle lewer ‘n wye reeks van toekomstige klimaatsvoorspellings vir die jaar 2063. Tydens die toets van die mees waarskynlike toekomstige klimaats-scenario, is bevind dat Bakoven kwesbaar is vir die verwagte vloeding a.g.v. seevlakstyging verwag teen 2063. Daar is ook bevind dat selfs tydens huidige storms, sommige strukture aan Bakoven se kus kwesbaar is. Die omgewingstoestande by Bakoven word beskou as voordelig vir die konstruksie van heipale as fondasies om die geboue hoër op te lig. As gevolg van streng munisipale regulasies met omgewings- en geskiedkundige bewaring as doel, is hierdie opsie egter nie moontlik nie. Dit word aanbeveel dat die regulasies wat deur regeringsamptenare daargestel word, aanpasbaar genoeg moet wees om die veranderende kusomgewing in ag te neem. Die moontlikheid en volhoubaarheid van ‘n akkommodasie oplossing, eerder as ‘n beskermings- of opgee benaderinge, moet deeglik ondersoek word vir elke ‘n individuele geval, in samewerking met die betrokke gemeenskap.

South Georgia is renowned for the abundance of Antarctic krill (Euphausia superba) and a range of krill predators. Variability in krill availability at a range of scales, and the consequences of this for predator-prey interactions, mean that quantifying the spatially explicit demand for krill by those predators is essential to understanding the mechanisms underlying ecosystem changes in the region. In this thesis demand within a distinct study box to the northwest of the island has been assessed. The thesis has three sections; (1) the number of predators; (2) the distribution of predators; and (3) the demand for krill by those predators. (1) Predator densities with confidence intervals were determined from appropriately designed shipboard transect survey; counts of Antarctic fur seals (Arctocephalus gazella), macaroni penguins (Eudyptes chrysolophus), gentoo penguins (Pygoscelis papua), and Antarctic prions (Pachyptila desolata) were adjusted for sea state, distance from observer and dive behaviour. Providing the first at-sea predator density estimates for the region. (2) A comparison of the distribution of female Antarctic fur seals engaged in pup-rearing (using satellite telemetry) and the whole population that were not restricted to a single part of the population (from shipboard transect survey) was undertaken. Using two general additive models based on the relationship between seal distribution (one derived from transect and the other from telemetry) and the physical environment indicated that the spatial distribution of lactating females is representative of the general population. (3) Using the derived predator density, the local krill demand estimate was 2581 tonnes krill per day, a consumption rate of 0.45% per day of the concurrently estimated krill biomass (using shipboard acoustics). Antarctic fur seals accounted for 75% of this demand. This level of demand was less than the increase in biomass resulting from krill growth. However, based on the length-specific demand, determined from concurrent predator diet samples demand exceeded growth for krill >48mm.

Chapter 1 Introduction. Chapter 2 Gross and microscopic visceral anatomy of the male Cape fur seal with reference to organ size and growth. Chapter 3 Age determination and growth in the male Cape fur seal: part one, external body. Chapter 4 Age determination and growth in the male Cape fur seal: part two, skull. Chapter 5 Age determination and growth in the male Cape fur seal: part three, baculum. Chapter 6 Suture age as an indicator of physiological age in the male Cape fur seal. Chapter 7 Sexual dimorphism in the adult Cape fur seal: standard body length and skull morphology. Chapter 8 Reproduction in the male Cape fur seal: age at puberty and annual cycle of the testis. Chapter 9 Diet and foraging behaviour of the Cape fur seal. Chapter 10(a) The Impact of the fur seal industry on the distribution and abundance of Cape fur seals. Chapter 10(b) South African Airforce wildlife rescue: Cape fur seal pups washed from Black Rocks, Algoa Bay, during heavy seas, December 1976. Chapter 11(a) Operational interactions between Cape fur seals and fisheries: part one, trawl fishing. Chapter 11(b) Operational interactions between Cape fur seals and fisheries: part two, squid jigging and line fishing. Chapter 11(c) Operational interactions between Cape fur seals and fisheries: part three, entanglement in man-made debris. Chapter 12 Concentrations of heavy metals (Cd, Cu, Pb, Ni & Zn) and organochlorine contaminants (PCBs, DDT, DDE & DDD) in the blubber of Cape fur seals. Chapter 13 Endoparasites of the Cape fur seal. Chapter 14(a) Preliminary investigations of shark predation on Cape fur seals. Chapter 14(b) Aggressive behaviour of an adult male Cape fur seal towards a great white shark Carcharodon carcharias. Chapter 15 Conclusions and future directions.

Tese de mestrado. Biologia (Biologia da Conservação). Universidade de Lisboa, Faculdade de Ciências, 2012
A otária Sul-Africana (Arctocephalus pusillus pusillus) é uma subespécie encontrada em zoos por todo o mundo, que se adapta geralmente bem a condições de cativeiro, reproduzindo-se com frequência. Não se encontra ameaçada pelo que, tal como a maioria dos pinípedes, é mantida em zoos principalmente por ser emblemática e ter um papel importante na atração e sensibilização dos visitantes. Apesar de potencialmente controversa, a manutenção de animais em cativeiro é o que permite aos zoos desenvolverem o seu papel na conservação, através da educação, investigação e envolvimento em projetos de conservação in situ e/ou ex situ. De qualquer modo, as condições em cativeiro estão longe de ser ideais, o que levou a uma preocupação em relação ao bem-estar destes animais nas últimas décadas. O bem-estar é geralmente avaliado em termos de saúde física, sucesso reprodutivo e bem-estar mental. Um dos indicadores mais comuns de baixos níveis de bem-estar mental é a ocorrência de estereotipias, que se definem como comportamentos repetitivos, invariáveis e sem nenhuma função aparente. Estes comportamentos desenvolvem-se como forma de lidar com instalações inadequadas e/ou um maneio inapropriado, quer no presente quer em fases cruciais da ontogenia do animal. As condições em cativeiro são frequentemente estéreis, excessivamente previsíveis e pouco complexas, podendo diferir bastante do ambiente em que a espécie evoluiu. Em cativeiro, o comportamento estereotipado mais comum em pinípedes é a natação circular, que pode chegar a representar 50% da atividade diária de alguns indivíduos. Na natureza, as otárias Sul-Africanas vivem na costa sudeste de África. A sua vida divide-se em três fases: acasalamento na primavera, renovação do pelo no verão e longos períodos de alimentação no outono e no inverno. No mar, conseguem mergulhar até mais de 200 m (embora a maioria dos mergulhos seja por volta dos 50 m). Durante a época de acasalamento, os machos estabelecem e defendem territórios e haréns. As fêmeas dão à luz quando chegam a terra e acasalam durante os dias seguintes. Fora da época de acasalamento não há territórios delimitados e não existe muita interação entre os animais, embora vivam vulgarmente em grupos quando em terra. Em zoos, as otárias não conseguem expressar todo o seu reportório comportamental, não podem caçar nem comer livremente e têm pouca escolha e controlo em relação ao ambiente em que se encontram. Estas condições são geralmente associadas a baixos níveis de bem-estar, sobretudo quando associadas a elas se diagnostica a exibição de comportamentos estereotipados. Um dos métodos mais comuns para contrariar estas condições é a utilização de técnicas de enriquecimento ambiental. Enriquecimentos frequentemente utilizados em pinípedes incluem presas vivas, blocos de gelo com peixe congelado, dispensadores de comida, objetos manipuláveis, mistura de mais do que uma espécie na mesma instalação e treino. Neste projeto foram aplicadas técnicas de enriquecimento ambiental a duas otárias Sul- Africanas (um macho e uma fêmea) mantidas em cativeiro no Aquário Vasco da Gama (Lisboa, Portugal). Os objetivos eram determinar 1) alterações no comportamento dos animais como resultado dos enriquecimentos e 2) o efeito de diferentes técnicas de enriquecimento. Foi previsto que ambos os animais interagiriam com os enriquecimentos, o que levaria a uma diminuição da natação circular, a um aumento de outros padrões comportamentais e à promoção de uma utilização mais equilibrada do espaço disponível (duas piscinas e duas plataformas interiores e uma instalação exterior). Todos estes resultados seriam indicadores de uma melhoria do bem-estar destes animais. O design experimental consistiu num período de quatro dias de amostragem antes, durante e após cada enriquecimento. As fases pós-enriquecimento funcionavam como baseline para o enriquecimento seguinte. Em cada dia ocorria uma sessão de amostragem de uma hora. O primeiro enriquecimento, “Random Fish”, consistiu em atirar peixes (quatro vezes, três peixes de cada vez) para diferentes áreas da instalação, sem nenhum aviso. O segundo, “Felt Curtain”, baseou-se na colocação de uma estrutura com tiras de feltro numa abertura através da qual os animais nadavam, criando uma cortina análoga a algas a flutuar. O terceiro enriquecimento foi a combinação dos dois anteriores. O quarto, “Textured Rugs”, consistiu em dois tapetes de plástico com pequenos pinos de um dos lados, criando uma textura diferente. Um foi preso a um local tipicamente usado para comportamentos de manutenção do pelo e o outro foi deixado livremente a flutuar. Para o quinto enriquecimento, “Fish in Ice”, utilizaram-se peixes congelados dentro de blocos de gelo. O último enriquecimento usado foi a combinação dos dois anteriores. Os resultados foram comparados através da interpretação de gráficos e análise estatística. As proporções de tempo passado em diferentes comportamentos e áreas antes, durante e após cada enriquecimento foram comparadas através de um teste de Friedman. A primeira e última baseline foram comparadas através de um teste Wilcoxon Signed Ranks, Em ambos os testes foi também calculado o p-value exato através de testes de permutações, uma vez que esta é a abordagem recomendada em estudos com pequenas amostras. Neste caso os animais foram analisados em separado e, devido às limitações estatísticas, este projeto foi considerado apenas como um caso de estudo, não pretendendo extrapolar em relação à espécie ou outros animais. Durante a baseline inicial, os dois animais passaram a maior parte do tempo em natação estereotipada na piscina direita. Este comportamento foi o mais frequente durante todo o estudo. A natação estereotipada nestes animais é realizada de uma forma circular e (quase sempre) no sentido dos ponteiros do relógio. O macho utiliza apenas a piscina direita mas a fêmea alterna entre usar só a piscina direita ou ambas as piscinas para cada volta. Os enriquecimentos “Random Fish” e “Fish in Ice” aumentaram comportamentos desejáveis, como a natação normal e comportamentos de alerta. Além disso, também promoveram uma utilização mais equilibrada do espaço da instalação. O macho monopolizava toda a comida, revelando uma clara hierarquia. Mesmo quando o macho não estava perto dos enriquecimentos alimentares a fêmea hesitava antes de interagir com eles. De uma maneira geral, estes foram os enriquecimentos mais eficazes e tiveram um efeito mais forte no macho do que na fêmea, tendo sido os únicos que tiveram algum efeito na diminuição da natação estereotipada Os enriquecimentos não alimentares, “Felt Curtain” e “Textured Rugs”, não causaram nenhuma alteração significativa no comportamento dos animais ou no uso do espaço. Os resultados sugeriram até que os animais os evitavam um pouco, mas nunca de um modo suficientemente intenso para serem considerados enriquecimentos negativos. A colocação da cortina levou à criação de uma rota alternativa na natação estereotipada da fêmea. Este resultado é positivo, uma vez que introduziu variabilidade num comportamento que geralmente tem um padrão fixo. A combinação de diferentes enriquecimentos mostrou que, para o macho, o efeito positivo dos enriquecimentos alimentares foi mais forte que um eventual desejo de evitar os não alimentares. Na fêmea observou-se o oposto. Este projeto mostra, assim, que o mesmo enriquecimento pode ter diferentes efeitos quando é apresentado sozinho ou em combinação com outro. É, por isso, importante testar todos os enriquecimentos individualmente e em associações antes de serem incorporados num plano de enriquecimento, assim como ter em conta a variação individual na resposta aos enriquecimentos. Por fim, não se observou nenhuma diferença entre a primeira e a última baseline, sugerindo que os resultados observados durante os enriquecimentos não tiveram um efeito duradouro. Estes animais estão sozinhos há bastante tempo, com pouca variabilidade na sua rotina diária e numa instalação muito pequena, estéril e com dois tanques circulares e pouco profundos. O evidente contraste com as condições naturais sugere que a natação circular seja o comportamento mais parecido com o reportório natural que os animais podem fazer nesta instalação. É também possível que a elevada ocorrência destes comportamentos estereotipados já não seja inteiramente reversível, por se tratarem de mecanismos de adaptação há muito estabelecidos. Nestas condições, o enriquecimento ambiental assume uma particular importância na introdução de variabilidade, como mecanismo de forçar a interrupção do padrão estereotipado da natação, substituindo-o por outros comportamentos. É também importante para estimular os animais a usarem o pouco espaço disponível de forma mais equilibrada. Baseado nos resultados deste estudo, com recomendações adicionais, pode ser aplicado um plano de enriquecimento sobretudo relacionado com alimento no maneio diário destes animais. Estes enriquecimentos demoram menos de cinco minutos a preparar, o que significa que não ocupam muito tempo do horário, geralmente sobrecarregado, dos tratadores. Adicionalmente, novos enriquecimentos devem ser testados para aumentar a variabilidade e evitar a habituação aos enriquecimentos atuais. Potenciais fontes de inspiração para novos enriquecimentos são a instalação exterior (raramente usada pelos animais neste momento) e o uso de técnicas de treino. O treino, baseado em princípios de reforço positivo, é uma das técnicas de enriquecimento ambiental mais usadas em mamíferos marinhos e é considerado bastante eficaz na estimulação cognitiva, física e social dos animais. Este projeto demonstrou que o enriquecimento ambiental teve efeitos benéficos no aumento de comportamentos desejados, na promoção de um uso mais equilibrado do espaço e na diminuição de comportamentos estereotipados, mesmo que apenas residualmente. Estas alterações têm um grande potencial na melhoria do bem-estar destes animais, que é uma obrigação ética essencial para a manutenção destes animais em cativeiro. O enriquecimento ambiental é, também, importante para garantir que estes animais sejam apresentados de forma adequada aos visitantes, de modo a transmitir uma mensagem apropriada. Como membro da EAZA (European Association of Zoos and Aquaria), o Aquário Vasco da Gama está envolvido em práticas conservacionistas, organizando frequentes visitas guiadas para escolas locais. Devido ao seu estatuto emblemático, torna-se então importante que estes dois indivíduos sejam percecionados pelos visitantes como representantes dos seus conspecíficos na natureza. Em conclusão, este projeto junta-se à já existente literatura que mostra que a relação custos/benefícios do enriquecimento ambiental é largamente compensatória para que seja aplicado como ferramenta na rotina de maneio de otárias em parques zoológicos.
South-African fur seals have been held at various zoos around the world, mostly due to their appeal to visitors. Captivity conditions differ from nature, leading to concerns over captive animals’ welfare. A common behavioural indicator of poor welfare is the occurrence of stereotypies, and a common method used to attempt to decrease them is environmental enrichment. In this project, enrichment techniques were applied to two South-African fur seals. There were two feeding enrichments (unpredictable fish thrown into the enclosure and ice blocks with frozen fish), two nonfeeding (an algae-like felt curtain and textured plastic rugs), and two combinations of the above. During the initial baseline, both animals spent the majority of time in stereotypical swimming, and in only one pool. The feeding enrichments increased non-stereotypical locomotion and alertness, and promoted a more balanced use of area. The non-feeding enrichments didn’t cause major changes but the curtain created a new stereotypical route for the female. Despite the tendency to reduce stereotypical swimming overall, enrichments did not reduce it significantly. There were no differences between the first and last baseline, suggesting that the effects didn’t outlast the enrichment periods. This is probably due to two concurrent reasons: the importance of swimming in their natural behavioural repertoire and their living conditions in captivity. These animals have been kept alone for a long time, with little variation in their daily routine and in an enclosure too small and barren. This project demonstrated that environmental enrichment had beneficial effects even if it only decreased stereotypical swimming marginally and can be developed in future studies, further exploring foodrelated enrichments, especially in their appetitive component. Adding this to the multitude of other positive studies, it seems that environmental enrichment has high enough benefits and low enough costs, to be applied as a common and mandatory husbandry tool.

The New Zealand fur seal (Arctocephalus forsteri) is the most abundant fur seal species in the Australian-New Zealand region. Approximately 85 % of Australia’s population of New Zealand fur seals reside in the state of South Australia. As a result of their abundance and size, it has been estimated that the New Zealand fur seal population in South Australia consumes the greatest biomass of resources of all marine mammal and seabird species. However, despite the importance of New Zealand fur seals as top predators, our understanding of their foraging ecology in South Australia is limited. In order to better understand the habitat utilized and the diet of New Zealand fur seals, this study explores the foraging ecology of lactating seals from four primary colonies in South Australia, which account for ~ 78 % of the Australian population. These colonies are Cape Gantheaume (36о04’S, 137о27’E) and Cape du Couedic (36о03’S, 136о42’E) on Kangaroo Island; North Neptune Island (35о13’S, 136о03’E) and Liguanea Island (34о59’S, 135о37’E). I start this study by assessing the seasonal variation in foraging location and dive behaviour of lactating New Zealand fur seals from Cape Gantheaume. 18 seals were fitted with satellite transmitters and time depth recorders (TDRs). The presence of thermoclines (derived from TDRs), were used as a surrogate measure of upwelling activity in continental shelf habitats. During the austral autumn 80 % of lactating fur seals foraged on the continental shelf (114 ± 44 km from the colony), in a region associated with a seasonal coastal upwelling system, the Bonney upwelling. In contrast, during winter months seals predominantly foraged in oceanic waters (62 %), in a region associated with the Subtropical Front (460 ± 138 km from the colony). Results suggested that lactating New Zealand fur seals shift their foraging location from continental shelf to oceanic habitats, in response to a seasonal decline in continental shelf productivity, attributed to the cessation of the Bonney upwelling in autumn. To study inter-colony differences in foraging locations, 21 New Zealand fur seals were satellite tracked from four colonies within close proximity (46 km – 200km apart). Seals initiated foraging trips on a colony-specific bearing (Cape Gantheaume 141 ± 33º, Cape du Couedic 186 ± 12º, North Neptune Island 200 ± 23º and Liguanea Island 234 ± 69º), and recorded little overlap between colony-specific foraging areas. The distribution of colony-specific foraging grounds appeared to be influenced by the proximity of colonies to predictable local upwelling features, as well as a distant oceanic frontal zone, the Subtropical Front. Foraging site fidelity and route-choice was further assessed by comparing site fidelity between continental shelf and oceanic habitats. Data from 31 lactating females, satellite tracked over 107 consecutive foraging trips indicated that females foraging on the continental shelf recorded a significantly greater overlap in foraging area between consecutive foraging routes, when compared to females that foraged in oceanic waters (55.9 ± 20.4 % and 13.4 ± 7.6 %, respectively). Findings suggest that seals learn the direction of travel to a predictable foraging region, and initiate a foraging trip on that bearing. However, actual foraging routes are likely to be influenced by a number of factors including previous foraging trip experience and prey encounter rate, which is related to prey density and the spatial scale of the patch exploited. The final chapter integrates scat analysis with milk fatty acid (FA) analysis to investigate dietary differences between continental shelf and oceanic waters. Milk FA composition was determined for 29 satellite-tracked fur seals, that were known to forage in either shelf or oceanic habitats. Based on FA compositions, I predicted the likelihood that milk samples collected at random (n = 131) represented individual seals having foraged either on the continental shelf or in distant oceanic waters. FA analysis and satellite tracking results contrasted with scat analyses, from which only 6 % of scats by frequency of occurrence contained prey remains from oceanic waters. The results suggest that scats were biased toward females foraging on the continental shelf. This study highlights the importance of two predictable ocean features utilised by New Zealand fur seals; (1) a nearby and seasonally predictable coastal upwelling system, the Bonney upwelling and; (2) a distant but permanent oceanic front, the Subtropical Front.
http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1347312
Thesis (Ph.D.) - University of Adelaide, School of Earth and Environmental Studies, 2008

New Zealand fur seals (Arctocephalus forsteri) show pronounced inter-sexual differences in adult body size, and males will potentially mate with many females. Consequently, selection is thought to act differently upon pups during growth. Little is known about how male and female fur seal pups conserve energy, and use milk for growth especially as they fast for significant periods. There has been a plethora of studies that have viewed pinnipeds as ideal models for the differential investment theory, but the evidence remains equivocal. This study investigated a species that has shown some support for differential investment in the past, in the form of pup growth and maternal attendance behaviour, and looked at the potential that these intersexual differences are due to differential utilisation of maternal resources (different body compositions) and/or differential fasting strategies by pups, which may be determined by fasting mass loss rates. This study hopes to encompass both aspects of differential investment, such as maternal attendance, as well as differential fasting strategies of pups by looking at their fasting mass loss rates. This study found that males were larger and longer throughout the lactation period, yet grew at the same rate as females. There was no detectable intersexual difference in the maternal provisioning provided by mothers, in the form of attendance. There was some evidence that males and females have different fasting strategies, in that females, from a subset of pups exhibited significantly higher mass specific mass loss rates. This finding should be treated with caution however, as sample size was low, and cross sectional samples revealed no significant differences. Furthermore, study of the activity rates of the same pups over the duration of the fast, found no significant intersexual differences in activity rates. These results suggest that further studies are needed that encompass both aspects of differential investment theory, as well as differential utilisation by pups.

M.Comm.
Du Plessis (1993:649) states that the most common reasons for business failure are the lack of understanding of the market and inferior products. The first point in Timmons' criteria list focuses on the industry and market. This is of utmost importance as no correct analysis of a new venture's viability can be done if there is not a full understanding by the potential investor of the exact market that he/she intends to venture into. Timmons does not highlight the importance of the product as such in his criteria list although inferior products are one of the most common reasons for failure. Timmons' fatal flaw aspect, point six, is however very important as it is an "abort checkpoint". If the venture has a fatal flaw, regardless of everything else being perfect, it could cancel the potential venture. This fatal flaw aspect is in line with Cartland's "subjective determination" criteria. Various probabilities are difficult or impossible to quantify accurately. If the entrepreneur is not totally convinced of the probability of success, it should be seen as a fatal flaw and the venture abandoned. Timmons' list of eight criteria is seen to incorporate the broadest and most appropriate checklist. Chapter three will concentrate on the industry, market and product in more detail, thus ensuring a thorough understanding of the market and product, avoiding one of the weaknesses in Timmons' criteria. In chapter four the business opportunity for echinoderms in South Africa will be evaluated against the eight factors as outlined especially by Timmons in this chapter.

This research is centred on designing a framework for application of systems engineering in non-conventional application areas. It uses the manufacturing – small and medium enterprises (SMEs) as a framing case. The system engineering approach (SEA) application and the value it brings is greatly appreciated in the traditional application areas like defence and aerospace industries, however, the SEA application in other industries particularly manufacturing has been very low. This has led to the mind-set that the formal systems engineering approach application is more practical and viable in high technology systems. The research focused on exposing the structural elements of the SEA combining the two systems engineering extremes (soft and hard systems) and proposing a framework tailored to the sophistication levels of the targeted manufacturing SMEs. The aim of the study was to illustrate that the SEA can be applied in other non-conventional applications areas. The Delphi study was used as the front-end primary research instrument to get input to build the conceptual framework. This involved a pilot study and a two round Delphi iteration exercise. Sixteen (16) expert‟s participated in round 1 while twelve (12) participated in round 2. This represents a response rate of 20% in the first round and 80% in the second round. An acceptable convergence of opinion of over 67% was achieved on most of the proposed SEA process activities targeted for the manufacturing SMEs. The tools required to validate the conceptual framework and frame the final implementation framework were then extracted. The study then proposed a conceptual implementation framework targeting the low to medium technology manufacturing SMEs. A sustainable hybrid SE framework is proposed in Chapter 7 which acknowledges the limitations and the constraints in the manufacturing SMEs in particular. This study adds to the body of knowledge of systems engineering by showing that a methodical approach can be followed in structuring a hybrid SEA for specific applications. The report concludes by recommending validating the proposed framework in pilot case study companies to provide useful comments and applicability levels within the targeted SMEs context.

Text in Afrikaans. Abstracts in Afrikaans, English and Zulu
This study explored how nine adolescent learner-participants with cerebral palsy or other physical disabilities responded to an emotional support programme (EOP) of 20 intervention sessions, aimed at developing their emotional intelligence. The research study highlighted the utilisational value and importance of emotional intelligence, which is associated with problem-solving skills, career success, selfactualisation, stress management and the like. The rationale for compiling the EOP was in accordance with the rationale for the research study, being embedded in diverse learning needs, support for learners, and the design of learner opportunities. The study focused among others on the development and implementation of an EOP based on Bar-On as conceptual model (2000), together with the five core competencies of social and emotional learning (SEL), namely: responsible decision-making, emotional self-awareness, self-management, social awareness, and relationship skills. The Lions Quest SEL-programme, Skills for Adolescence, formed the basis of the EOP, although the researcher had to adapt it for her learner-participants’ special educational needs. The EOP was further extended with the knowledge obtained through the literature study regarding emotional intelligence and adolescence, and was aligned with the aims of the South African school curriculum in respect of emotional intelligence skills, as stated in the aims of the subject Life Skills. The researcher’s embedded, mixed-method research design allowed the larger qualitative component to include the smaller quantitative component, so that the specific phenomenon could be understood from different participants’ perspectives. Qualitative data was collected by means of metaphor interviews and collage activities. The quantitative research component of the study refers to the standardised Bar-On Emotional Quotient Inventory: Youth Version (EQ-i:YV) together with the researcher’s own structured questionnaire. The researcher did not interpret the data obtained from the quantitative data collection instruments in isolation, but used it to expand and verify the results of her qualitative generated data. The integrated data results of the learner-participants brought the answer to the research problem: most of the adolescent learner-participants with special educational needs who had participated in the EOP, did indeed benefit through their involvement, and their emotional intelligence (the phenomenon under scrutiny) had improved.
Die studie ondersoek hoe nege adolessente leerder-deelnemers met serebrale en fisieke gestremdhede op ’n emosionele ondersteuningsprogram (EOP) van 20 intervensiesessies reageer met die doel om hulle emosionele intelligensie te ontwikkel. Die benuttingswaarde en belangrikheid van emosionele intelligensie word deur die navorsingstudie uitgelig. Hoë emosionele intelligensie word geassosieer met probleemoplossingsvaardighede, werksukses, selfverwesenliking en streshantering, onder andere. Die rasionaal vir die samestelling van die EOP stem ooreen met die rasionaal vir die navorsingstudie en is gevestig in uiteenlopende leerbehoeftes, ondersteuning aan leerders, en die skep van leergeleenthede. Die studie fokus op die samestelling en implementering van ’n emosionele ondersteuningsprogram (EOP) gebaseer op Bar-On (2000) se konstruk van emosionele intelligensie as konseptuele model van die studie saam met die vyf kernbevoegdhede van sosiale en emosionele leer (SEL), naamlik: verantwoordelike besluitneming, emosionele selfbewussyn, selfbestuur, sosiale bewussyn en verhoudingsvaardighede. Die Lions Quest SEL-program, Skills for Adolescence, vorm die grondslag van die EOP, alhoewel die navorser baie aanpassings vir haar leerder-deelnemers se spesiale onderwysbehoeftes moes maak. Die EOP is verder uitgebrei deur die kennis wat die navorser tydens die literatuurstudie ingewin het ten opsigte van emosionele intelligensie en adolessensie, en sluit aan by die Suid-Afrikaanse skoolkurrikulum-doelwitte wat verband hou met emosionele intelligensie-vaardighede soos uiteengesit in die doelwitte vir die vak Lewensvaardighede. Die navorser se ingebedde, gemengdemetode-navorsingsontwerp laat toe dat die groter kwalitatiewe komponent die kleiner kwantitatiewe komponent insluit, sodat die spesifieke fenomeen vanuit verskillende deelnemers se perspektiewe verstaan kon word. Kwalitatiewe data is deur middel van die metafooronderhoud en collage-aktiwiteit ingesamel. Die kwantitatiewe navorsingskomponent van die studie verwys na die gestandaardiseerde Bar-On Emotional Quotient Inventory: Youth Version (EQ-i:YV) tesame met die navorser se eie gestruktureerde vraelys. Die navorser het die data wat sy uit die kwantitatiewe datainsamelingsinstrumente verkry het, nie net in isolasie geïnterpreteer nie, maar dit ook gebruik om die resultate van haar kwalitatief-gegenereerde data uit te brei en te verifieer. Die geïntegreerde data-resultate van die leerder-deelnemers bied die antwoord op die: die meerderheid van die adolessente leerderdeelnemers met spesiale onderwysbehoeftes wat aan die EOP deelgeneem het, het inderdaad gebaat by hulle deelname, en hulle emosionele intelligensie (die fenomeen wat ondersoek is) het verbeter.
Ucwaningo luhlola ukuthi ngabe ukuzibandakanya kwabafundi abangabadlalindima abayisishiyagalolunye abasesigabeni sobubhungu/sobutshitshi abakhubazeke ngokwengqondo noma ngayiphi indlela emzimbeni baphendule kanjani kuhlelo oluxhasa ngokommoya (emotional support programme) kumihlangano engama- 20 yokunceda, ehlose ekuqiniseni ubuhlakani bommoya. Isifundo socwaningo siveze ukubaluleka kokusebenzisa kanye nokubaluleka kobuhlakani bommoya, okuhambisana namakhono okuxazulula izinkinga, impumelelo yobizo lomsebenzi, ukuzibonakalisa, ukulawula ingcindezi yengqondo kanye nokunye. Isizathu sokuhlela i-ESP sasihambisana nenhloso yesifundo socwaningo, esitholakala kwizidingo zemfundo ezahlukahlukene, kanye nokuhleleka kwamathuba omfundi. Ucwaningo lubheke hlangana nokunye nokuthuthukiswa kanye nokusetshenziswa kohlelo lwe-ESP olususelwa ku-Bar-On njengemodeli yegama (2000), kanye namanye amacebo abalulekile amahlanu ohlelo lokufunda kwabantu kanye nokufunda ngokwemizwa (SEL), wona yilawa alandelayo: Ukumelana nezinqumo ozithethe, ukwazi imizwa yakho, ukuziphatha ngokwakho, ukuxwayiswa komphakathi kanye namakhono okwenza ubudlelwano. Uhlelo lwe- Lions Quest SEL, Skills for Adolescence, akha isisekelo se-ESP, yize umcwaningi kwakufanele aluguqule lolu hlelo ukwenzela ukuba luhambisane nezidingo ezikhethekile zemfundo yafundi abadlala indima. . Uhlelo lwe--ESP lwaqhubeka nokukhuliswa ngolwazi olwalutholakala ngocwaningo lombhalo wobuciko obumayelana nobuhlakani bokusebenzisa imizwa kanye nesigaba sobutshitshi/sobubhungu, kanti lolu hlelo lwaluhambisana nezinhloso zekharikhulami yezikole zaseNingizimu Afrika mayelana namakhono okusebenzisa obuhlakani bokusebenzisa imizwa, njengoba kushiwobkwizinhloso zesifundo samaKhono Empilo (Life Skills). Isakhiwo somcwaningi esequkethwe, sohlelo-oluvangene locwaningo siye savumela isigaba esikhulu socwaningo olugxile kukhwalithi (qualitative) ukuba sixube isigaba esincane esigxile kumanani (quantitative), ukuze kuzwisiseke uhlelo oluthize ngokwemiqondo yabadlalindima abehlukahlukene. Idatha yohlelo lwequalitative yaqoqwa ngokusebenzisa izinhlolombono zokungathekisa kanye nemisebenzi yokuhlanganisa imifanekiso eminingi. Isigaba socwaningo olugxile kumanani sichaza uhlelo olufanayo lwe--Bar-On Emotional Quotient Inventory: Youth Version (EQi:YV) kanye nemibhalo yemibuzo ehlelwe wumcwaningi. Umcwaningi akazange achaze idatha etholakele kumathuluzi okuqoqa idatha encike kumanani yodwa, kodwa le datha iye yasetshenziselwa ukukhulisa kanye nokuqinisekisa imiphumela yakhe eyakhiwe ngokwendlela yekhwalithi. Imiphumelo ehlangene yedatha yomfundi ongumdlalindima ilethe impendulo kwinkinga yocwaningo: Iningi labafundi abadlala indima abasesesigabeni sobubhungu/sobutshitshi abadinga imfundo ekhethekile abazibandakanye ohlelweni lwe-ESP, ngempela baye bazuza ngokuzibandakanya kwabo, kanti-ke izinga labo lokusebenzisa ikhono lobuhlakani bemizwa buye bathuthuka kakhulu (the phenomenon under scrutiny).
Inclusive Education
D. Ed. (Inklusiewe Onderwys)