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Arlt, Debora. "Habitat selection : demography and individual decisions /." Uppsala : Dept. of Ecology, Swedish University of Agricultural Sciences, 2007. http://epsilon.slu.se/200717.pdf.
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Cushman, Susan Flanders. "Fish movement, habitat selection, and stream habitat complexity in small urban streams." College Park, Md. : University of Maryland, 2006. http://hdl.handle.net/1903/3873.
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Thesis (Ph. D.) -- University of Maryland, College Park, 2006.Thesis research directed by: Marine-Estuarine-Environmental Sciences. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.
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Ignatiuk, Jordan B. (Jordan Blake). "Breeding biology and habitat selection of American crows in Saskatchewan parkland habitat." Thesis, McGill University, 1991. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=60454.
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The breeding biology and nest-site selection of American crows (Corvus brachrhynchos) was studied in 2 areas of aspen parkland habitat in Saskatchewan in 1987 and 1988.Overall, density of nests at St. Denis averaged twice that found at Elstow and clutches were initiated earlier at St. Denis than at Elstow. Clutch size and hatching success did not differ between years or areas, but in 1987, nests at St. Denis produced nearly twice as many young as at Elstow.
Crows nested in willow, aspen, and other trees. Nest trees were larger than randomly-selected trees in both years and areas. At St. Denis, the area near active crow nests had, on average, more permanent wetlands, a greater proportion of pasture and wetland, and less area of cultivation than areas adjacent to random sites. At St. Denis, successful nests were closer to permanent water and had more permanent wetlands nearby than depredated nests, but discriminant function analysis could not correctly distinguish successful nests in either area. Selection of nest characteristics to evade predators does not appear to provide predictable advantages to breeding crows.
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Koskela, A. (Anni). "Wolverine habitat selection, diet and conservation genetics." Doctoral thesis, Oulun yliopisto, 2013. http://urn.fi/urn:isbn:9789526202273.
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Abstract Rare and elusive species are difficult to study, because they are usually secretive, solitary, occur at low densities and have large home ranges. Wolverines (Gulo gulo) can both hunt and scavenge for food. In Fennoscandia, wolverines co-exist with either wild or semi-domesticated reindeer, which constitute their most important winter food. Approximately half of the 180–220 Finnish wolverines are found in northern Finland within the reindeer management area. However, the other half of the population is distributed in eastern and central Finland, and the ecology of wolverines especially in this area is poorly known. This research examined the habitat selection, diet and population genetics of wolverines in northern and eastern Finland. The results suggest that wolf presence is one of the most important variables influencing the habitat selection of wolverines. This finding supports the speculative idea that wolverines might benefit from being sympatric with wolves through increased scavenging opportunities. Furthermore, both the reproductive status of wolverines and the availability of different prey items were found to affect the wolverine diet. In northern Finland, semi-domesticated reindeer and mountain hare were the most frequently utilized prey species for breeding female wolverines. In eastern Finland, the most important food source for breeding females was moose carrion, whereas males and non-breeding females heavily utilized mountain hares. These results support the predictions of the optimal foraging theory, suggesting that wolverines opportunistically utilize the food source that is most energy-efficiently available. In areas with a low density of medium-sized ungulates, scavenging of wolf- and human-killed carrion plays an essential role in food acquisition by wolverines. According to the results of a population genetics investigation, two wolverine subpopulations exist in Finland: a northern and an eastern one. The overall genetic variability was found to be low, and signs of a recent population bottleneck were detected in both populations. It is likely that the wolverine populations in Finland would benefit from improved connectivity between them, but also with neighbouring populations in Scandinavia and north-eastern RussiaTiivistelmä Ahma (Gulo gulo) tunnetaan sekä haaskansyöjänä että keskikokoisia hirvieläimiä ja pienriistaa saalistavana petona. Fennoskandian alueella peuran kesy tai villi muoto on ahman merkittävin saalislaji. Noin puolet Suomen 180–220 ahmasta elää Pohjois-Suomessa poronhoitoalueella, ja loput Itä- ja Keski-Suomessa. Poronhoitoalueen ulkopuolella elävien ahmojen ekologiaa on tutkittu erityisen vähän. Väitöstyössäni tarkastelin ahman habitaatinvalintaa, ruokavaliota ja populaatiogenetiikkaa pääasiassa Pohjois- ja Itä-Suomen alueilla. Tutkimukseni tulokset osoittivat, että suden läheisyys oli yksi tärkeimmistä ahman habitaatinvalintaan vaikuttavista tekijöistä. Tämä havainto tukee hypoteesia, jonka mukaan ahma saattaisi hyötyä susien läheisyydestä suuremman haaskatiheyden ansiosta. Todennäköisesti ahmat elävät mielellään samoilla seuduilla susien kanssa, mutta kaihtavat läheistä kanssakäymistä välttääkseen killansisäisen saalistuksen. Tutkimusteni perusteella sekä ahman lisääntymistila että alueen saaliseläinten saatavuus vaikuttivat ahman ruokavalioon. Poro ja metsäjänis olivat lisääntyvien ahmanaaraiden tärkein ravintokohde Pohjois-Suomessa. Itä-Suomessa merkittävin lisääntyvien naaraiden ravintokohde oli hirvi, jota ahmat hyödyntävät lähinnä haaskojen muodossa, mutta urokset ja ei-lisääntyvät naaraat sen sijaan saalistivat eniten metsäjänistä. Ahmat siis näyttävät hyödyntävän opportunistisesti sitä ravintokohdetta, joka kullakin alueella on energiatehokkainta saavuttaa. Susien ja ihmisten jälkeensä jättämät haaskat ovat merkittävä ravintolähde ahmoille alueilla, joilla keskikokoisten hirvieläinten tiheydet ovat alhaisia. Ahman populaatiogeneettinen tutkimus osoitti, että Suomen ahmat ovat geneettisesti jakautuneet kahteen alapopulaatioon, pohjoiseen ja itäiseen. Ahmakannan geneettinen monimuotoisuus oli pientä, ja molemmissa alapopulaatiossa oli nähtävissä merkkejä äskettäisestä pullonkaulailmiöstä. Populaatioiden välisen geenivirran määrän tulisi olla nykyistä korkeampi, jotta ahmakannan elinvoimaisuuden voisi katsoa olevan turvattu tulevaisuudessa
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Knight, Thomas W. "Habitat selection in Brook Trout, Salvelinus fontinalis /." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape2/PQDD_0033/NQ62450.pdf.
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Rangeley, Robert W. (Robert William). "Habitat selection in juvenile pollock, Pollachius virens : behavioural responses to changing habitat availability." Thesis, McGill University, 1994. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=28648.
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This thesis demonstrates how tidal changes in the availability of intertidal zone habitats can affect the distribution and behaviour of juvenile pollock (Pollachius virens). Schools of pollock moved from the subtidal zone to the open habitat in the intertidal zone. On rising tides, pollock switched from the open habitat at low tidal stages to the dense algal habitat at high tidal stages. On falling tides, pollock rapidly schooled downshore in the open habitat. Pollock were rarely solitary in the open habitat and usually formed large schools. In the algal habitats, pollock were usually dispersed and preferred the dense algae over the sparse algae. Predation risk from birds was widely distributed among depths, habitats and stages of the tide, during the day. In a mesocosm experiment, pollock increased their use of the algal habitat and were more difficult to detect following a simulated bird predator threat. Preference for the algal habitat was density-dependent when either pollock abundance or algal habitat area were manipulated. Pollock responded to their potentially high density in the algae by schooling in the open habitat.
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Catton, Robert Bruce. "Winter use and habitat selection of moose in openings and adjacent upland forested habitats." Thesis, University of British Columbia, 2007. http://hdl.handle.net/2429/31919.
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Two designs were developed to model and compare the effects of scale on resource utilization by
moose in a managed lodgepole pine (Pinus contorta) forest. Statistical models, based on
population and individual design levels (using microsite and moderate polygon habitat scales,
respectively), were used to 1) test the hypotheses that moose track presence was increased i) in
openings of increasing shrub cover, ii) in forests adjacent to openings of increasing shrub cover,
2) model moose utilization of forest cover, based on distance-from-nearest-opening, to determine
appropriate leave strip widths adjacent to openings used by moose, 3) further understanding of
how different opening and forest cover types influence moose presence and utilization and 4)
compare these results from the different designs. Moose track occurrence and habitat attributes
were recorded on 55 snow track transects to model moose presence as a function of distance-from-
opening-edge and variation in vegetation cover. Over 15,000 UTM relocations were
obtained from 15 GPS collared cow moose over two winters, in the same area. Based on track
transect data, the model containing bog birch (Betula glandulosa), Salix species and mean shrub
height was the best predictor of moose presence. Resource utilization functions indicated natural
and forest management openings, up to 40 years old, were utilised more than older forest
habitats. Modeling at both scales confirmed the use of early seral openings (natural or
harvested) and indicated that forested distance-from-an-opening-edge does not influence resource
utilization or presence of moose. Track presence was greater in wetlands with average shrub
cover between 6 - 20% and > 20% than within adjacent forest cover but there was no difference
between wetlands with shrub cover < 6% and adjacent forest cover. Tracks were more numerous
in forest cover adjacent to wetlands with shrub cover > 20% than in forest cover adjacent to wetlands with shrub cover < 6% and 6 - 20%. The study implies that leave strips may have little
immediate effect on the use of early seral openings by moose in winter although, this does not
rule out that climate, predation or hunting pressure will influence habitat selection in the future.Forestry, Faculty of
Graduate
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Jones, Carys Wynn. "Habitat and rest site selection in polymorphic Lepidoptera." Thesis, University of Cambridge, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.358332.
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Smith, Dustin M. "Habitat selection and predation risk in larval lampreys." Morgantown, W. Va. : [West Virginia University Libraries], 2009. http://hdl.handle.net/10450/10493.
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Brockman, Julia C. "HABITAT SELECTION OF REINTRODUCED BISON IN NORTHERN ILLINOIS." OpenSIUC, 2017. https://opensiuc.lib.siu.edu/theses/2187.
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In one of the first reintroductions of a semi-wild population of bison (Bison bison) east of the Mississippi River, The Nature Conservancy reintroduced bison to the Nachusa Grasslands in northern Illinois in October 2014. Given the novelty of such efforts, questions remain regarding how human activity and prairie management affect bison habitat selection. My objective was to quantify bison habitat selection during 2014-16 to address literature gaps while investigating seasonal and annual changes. In October 2014, The Nature Conservancy collared 7 female bison with Lotek Iridium TrackM 3D and 4D collars programmed to take hourly locations. I randomly selected 1 bison location each hour to represent herd location and divided the resulting locations by season. Using resource selection functions, I compared the influence of land cover type, fire management, and concentrated human activity on habitat selection across seasons and at 2 scales: patch and enclosure. Land cover was consistently the best-fit model across seasons and scales with the exception of Winter 2016 at the enclosure scale. Bison strongly selected for partial restorations but showed no strong seasonal land cover selection trends. Bison selected for recently-burned prairie with the exception of Summer 2015 at the enclosure scale. At the patch scale, bison selected for areas closer to disturbed areas but did not show a strong trend at the enclosure scale. With a better understanding of how bison grazing is influenced by restoration management, wildlife managers can make better-informed decisions regarding bison restoration and public use.
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Scott, Cody B. "Behavioral Characteristics Affect Habitat Selection of Domestic Ruminants." DigitalCommons@USU, 1995. https://digitalcommons.usu.edu/etd/6488.
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I evaluated some of the factors affecting livestock distribution by conducting experimental (Chapters II and III) and observational (Chapter IV) studies. In Chapter II, I described the effect of locations of familiar foods and social interactions on choice of feeding location by lambs. Lambs were exposed to a pasture as subgroups of strangers and companions with different dietary habits (i.e., three lambs that preferred milo with three lambs that preferred wheat). Milo was placed on one end and wheat on the other, about 100 m apart. Strangers typically fed in different locations, reflecting dietary preferences. Conversely, companions fed in both single subgroups and in separate subgroups because both social interactions and dietary preferences affected choice of feeding location.
The objective of Chapter III was to evaluate the effect of experience with a pasture on choice of feeding location. Lambs with different levels of familiarity with the pasture were exposed as subgroups with different dietary habits. Lambs familiar with the pasture typically fed in separate locations, reflecting dietary preferences. Lambs naive to the pasture always fed in one subgroup and consumed both foods because social interactions overrode dietary preferences.
Results in Chapter IV describe cattle observations on a 1,030-ha grazing allotment. Cattle home ranges were similar in location (i.e., site fidelity) between 1990 and 1991, even though home ranges increased in size and (or) shifted in location in response to water availability. Moreover, forage availability did not account for changes in home range size or location. Site fidelity probably developed because of experiences early in life while foraging with mother and (or) peers.
Managers may be able to improve distribution by manipulating foraging experiences. Placing familiar foods/supplements in underutilized areas, controlling the amount of experience livestock have with different habitat types, and culling animals that spend a disproportionate amount of time in riparian zones may improve · distribution. Herding could also improve distribution. Herding integrates social interactions and experience with foods by controlling the exposure of social groups to particular foods and habitats. Nevertheless, livestock may still spend considerable time in riparian zones unless other watering points are available.
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Carrière, Suzanne. "Habitat selection by sympatric black ducks and mallards in Abitibi, Quebec." Thesis, McGill University, 1991. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=59984.
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Habitat use by sympatric black ducks (Anas rubripes) and mallards (A platyrhynchos) was studied in Abitibi, Quebec during May-August 1988 and 1989.Black duck broods preferred emergent and shrub-rich areas in both years. Mallard broods' habitat use differed from 1988 to 1989 (from emergent to shrub-emergent areas) when average water levels were higher. Diversity of habitats seems more important to rearing black ducks than to mallards. Rearing mallards seem to modify their use of habitats according to changing habitat availability. Daily survival rates differed only slightly between "species".
Telemetry was used to study wetland use by six mallard and three black duck non-breeding females. Swamps were preferred whereas ericaceous shrub wetlands were avoided by both "species". Beaver (Castor canadensis) ponds were extensively used during the moulting period. Home ranges averaged 302.7 ha for black ducks and 201.2 ha for mallards.
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Olovsson, Anders. "Habitat selection by moose (Alces alces) in southwestern Sweden." Thesis, Karlstad University, Faculty of Social and Life Sciences, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-1033.
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The moose (Alces alces) is very important both economically and ecologically, therefore all knowledge of moose is vital for future management of the moose population. Little is known about moose habitat selection in Sweden. In coastal southwestern Sweden growing human population and new infrastructure projects continuously threaten to fragment and isolate local moose populations. The habitat selection of 22 moose, 8 males and 14 females, in southwestern Sweden was studied from February 2002 until December 2005. The moose were captured and fitted with GPS-collars and positions were collected at 2-hour intervals. The number of moose positions totaled 71103 during the study period of 46 months. Data for individual animals were divided into four seasons: spring, summer, fall and winter based on climate and moose biology. A total of 125 moose seasonal home ranges were generated and habitat use within each of the generated home ranges was studied using Euclidean distance-based analysis. A reclassified digital landcover map was divided into the land use classes agriculture, clear-cut, coniferous forest, deciduous forest, mire and mountain. The results showed that there was a difference in habitat selection between males and females. Males were significantly closer to forest and clear-cuts compared to females. Both males and females selected clear-cuts and avoided agriculture within their home ranges.
Älgen är en viktig art, både ekonomiskt och ekologiskt, och all kunskap är viktig för att även i framtiden kunna sköta en sund älgstam. Trots flertalet studier finns det många frågetecken om älgens habitatval i Sverige. En ökad exploateringstakt och nya infrastrukturprojekt hotar att fragmentera och isolera populationer av älg. Habitatvalet hos 22 älgar, 8 tjurar och 14 kor, i sydvästra Sverige studerades mellan februari 2002 och december 2005. Älgarna sövdes och utrustades med GPS-sändare, deras positioner registrerades varannan timma och det totala antalet positioner under den 46 månader långa studietiden var 71103 stycken. Data från varje älg delades in i 4 säsonger; vår, sommar, höst och vinter, baserat på klimat och älgens biologi. Totalt genererades 125 hemområden baserade på säsong, och valet av habitat inom varje hemområde studerades med hjälp av Euclidean distance-based analysis. En omklassificerad digital marktäckedata användes som var indelad i 6 olika klasser; odlad mark, hygge, barrskog, lövskog, myrmark och berg i dagen. Resultaten visade att det var skillnad mellan könen i hur de väljer habitat. Tjurarna var signifikant närmare barrskog och hyggen än korna, men både tjurar och kor selekterade för hyggen och undvek odlad mark inom deras hemområden.
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Hartman, Patricia J. "HABITAT SELECTION OF THE CERULEAN WARBLER IN EASTERN KENTUCKY." UKnowledge, 2006. http://uknowledge.uky.edu/gradschool_theses/285.
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Successful forest management requires an understanding of the habitat requirements of individual species at multiple spatial scales. The cerulean warbler (Dendroica cerulea) is a neotropical migratory songbird that has recently gained widespread attention as a species of conservation and management concern. It breeds in mature, deciduous forests of eastern North America and has experienced precipitous range-wide declines over the last 40 years. Although Kentucky likely supports one of the largest breeding populations of the species, no information exists on cerulean warbler habitat selection within the state. The overall purpose of this study was to identify important habitat features associated with cerulean warbler distribution on breeding grounds in eastern Kentucky. In 2004 and 2005, I examined cerulean warbler distribution and associated vegetative characteristics within a hierarchical framework at the stand, territory, and nest-site levels. I used the Information-Theoretic approach to develop 2 sets of a priori models. The first set of models attempted to explain cerulean warbler site occupancy through presence and absence data obtained from point counts. The second set of models attempted to explain differences between preferred song perches and available habitat. Due to small sample size, nest-site information was not used in modeling efforts. Results from presence and absence modeling were inconclusive as no habitat-related differences were identified between occupied and unoccupied locations within the study area. However, territory modeling revealed three potentially important predictors of cerulean warbler habitat: large diameter trees, east-facing aspect, and increased shrub cover. This study reinforces general patterns observed throughout the cerulean warblers breeding range. Although the mechanisms causing cerulean warbler declines are still poorly understood, conservation and management efforts directed toward protecting and establishing large tracts of mature forest with large trees on mesic, sheltered sites should be a reasonable approach to managing cerulean warbler populations on the breeding grounds.
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Sands, Timothy. "Habitat preference and selection in a Bombina hybrid zone." Thesis, University of Edinburgh, 2005. http://hdl.handle.net/1842/14349.
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This thesis describes novel data about reproductive isolation between the toad species Bombina bombina and Bombina variegata in a mosaic hybrid zone at Apahida in north-west Romania. The hybrid zone at Apahida forms a fine-scaled mosaic, with the genetic composition of subpopulations varying with the aquatic habitat, even over small distances. I conducted a mark-recapture study which showed that adults move between sites at a high rate and move over distances greater than those separating different habitat types. Variation between sites could be maintained with this movement pattern if there is habitat preference. I use mark-recapture data to test for evidence that adult Bombina are choosing their sites with a preference that correlates with allele frequency at neutral loci; the conclusions vary depending on the assumptions of the analysis. An adult habitat preference for mating site can result in the continuation of the habitat association in the next generation. I test for evidence of this in the genotypes of the resulting eggs, and find no evidence that habitat preferences create habitat associations. Morphology also varies between habitats. I examine the distribution and association of quantitative traits across the hybrid zone. This demonstrates that considerable dispersal occurs from sites whose populations are most similar to the pure species to sites of intermediate phenotype. It also provides some evidence that pure species combinations of these traits are favoured over mixed combinations. These results show that the habitat association of adult Bombina may not be as important in preventing introgression as it would first appear. However it also reveals that major changes to the composition of populations occur between egg laying and adulthood, changing the frequency of neutral alleles and generating linkage disequilibria and a deficit of heterozygotes.
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Berner, Louis Robert 1963. "Habitat selection by mountain sheep in Mojave Desert scrub." Thesis, The University of Arizona, 1992. http://hdl.handle.net/10150/278189.
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I identified habitat use by 12-18 mountain sheep (Ovis canadensis nelsoni) in a 320-ha enclosure between June 1990 and June 1991 on the Desert National Wildlife Refuge, Nevada. The enclosure included 9 vegetation associations and 5 slope classes. I used a non-mapping technique and line transects to determine availability of vegetation associations and slope classes, and species composition, respectively. I determined use of habitats by mountain sheep with instantaneous sampling. Mountain sheep used midslopes and draw associations on the west side of the study area, and slope classes of 36-80% more than expected based on availability. I tested Hansen's (1980) habitat evaluation model on the study area. The model was >98% accurate in predicting mountain sheep use of habitat. Habitat use by mountain sheep in the enclosure was similar to habitat use of free-ranging mountain sheep.
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Maletzke, Benjamin Thomas. "Winter habitat selection of lynx (Lynx canadensis) in northern Washington." Online access for everyone, 2004. http://www.dissertations.wsu.edu/Thesis/Summer2004/b%5Fmaletzke%5F081704.pdf.
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Pakanen, V. M. (Veli-Matti). "Linking demography with dispersal and habitat selection for species conservation." Doctoral thesis, Oulun yliopisto, 2011. http://urn.fi/urn:isbn:9789514296352.
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Abstract In conservation biology, informed and sound management decisions depend on target specific information about the life history and demography of the endangered populations. I used long-term, individual-based life history data (breeding and capture-recapture data) to examine life-history and demography in order to assess population viability and management. My study systems consist of metapopulations of two endangered, long-distance migratory wader species breeding on Baltic coastal meadows, the Temminck’s stint (Calidris temminckii) and the Southern Dunlin (Calidris alpina schinzii), whose breeding habitats are mainly managed by livestock grazing. Demographic models indicated that both study populations were sinks, which persist through immigration due to low local recruitment insufficient to compensate for adult mortality or emigration. Philopatric Temminck’s stints had higher nest and apparent adult survival compared to immigrants. Consideration of dispersal status in population models resulted in the most realistic estimates of population growth and revealed a low demographic impact of immigrants. Immigrants had low return rates after reproductive failure, suggesting that the difference in apparent survival was partly caused by different breeding dispersal strategies. Thus, management actions improving reproduction, and thus site fidelity, should also influence viability. An artificial nest experiment indicated high trampling rates under recommended stocking rates on managed meadows. This was attributed to similar space use of nesting Dunlin and cattle. Cattle presence did not affect nest predation. Young Dunlin preferred intensively grazed low sward habitat over high sward habitat. Reproductive success was also higher in low sward habitat. However, nests in the preferred habitat had the highest risk of being trampled if not artificially protected. Thus, low sward habitat was found to work as an ecological trap if grazing was started too early in the breeding season. Due to the sink nature of the Dunlin population even small reductions in reproductive success caused by trampling were detrimental to long term viability. The results encourage continuation of the use of cattle grazing as a management tool, but also highlight the need for more detailed consideration of local grazing practices, especially when sketching management plans for endangered speciesTiivistelmä Uhanalaisten lajien suojelussa tehokkaiden suojelutoimien suunnittelu edellyttää tietoa hoitokohteen elinkierron eri vaiheista ja niiden demografisesta merkityksestä. Käytän tutkimuksessani pitkäaikaisaineistoja (pesintä ja merkintä-takaisinpyynti) kuvatakseni tutkimuslajien demografiaa ja arvioidessani populaatioiden elinkykyä sekä hoitotoimia. Tutkimuskohteinani ovat lapinsirrin ja etelänsuosirrin, kahden uhanalaisen kahlaajan, Perämeren rantaniityillä pesivät metapopulaatiot. Näiden lajien elinympäristöjä hoidetaan pääosin laiduntamalla. Demografinen mallinnus osoitti molempien populaatioiden olevan nielupopulaatioita, joiden säilyminen on tulomuuton varassa sillä poikastuotto ei kompensoi aikuisten kuolleisuutta ja poismuuttoa. Tutkimusalueella syntyneiden ja sinne rekrytoituneiden lapinsirrien pesä- ja aikuissäilyvyydet olivat paremmat kuin tulomuuttajilla. Tämän huomioiminen populaatiomalleissa tuotti realistisimman kasvukertoimen arvion ja osoitti paikallisten rekryyttien olevan tulomuuttajia merkittävämpiä populaation kasvun kannalta. Pesinnässään onnistuneet tulomuuttajat palasivat seuraavina pesimäkausina epäonnistuneita todennäköisemmin. Paikallisilla rekryyteillä vastaavaa eroa ei havaittu. Ilmiö heijastellee tulomuuttajien muuttoalttiutta myöhemminkin ja voi kertoa erilaisista pesimädispersaalistrategioista. Lisääntymismenestyksen parantaminen voisi parantaa elinkykyä myös pienentämällä poismuuttoa. Tekopesäkokeen perusteella pesien tallausriski oli laidunnetuissa ympäristöissä korkea vaikka laidunnuspaine noudatteli hoitosuosituksia. Tämä johtunee ainakin osin laskennallista korkeammasta todellisesta laidunpaineesta, mikä puolestaan johtui lintujen ja karjan yhtäläisestä tilankäytöstä. Rekrytoituvat suosirrit suosivat voimakkaasti laidunnettuja matalakasvuisia niittyjä, joissa poikastuotto oli parempi kuin, laiduntamattomilla niityillä. Toisaalta, tallausriski on voimakkaasti laidunnetuilla niityillä suuri ja jo pienetkin pesätappiot uhkaavat suosirripopulaation elinkykyä. Täten laitumet voivat toimia ns. ekologisina loukkuina, jos laidunnus aloitetaan liian aikaisin suhteessa pesintään. Laidunnus on kuitenkin suositeltava hoitomuoto, sillä se näyttää tuottavan parhaita pesimäympäristöjä etelänsuosirrille. Tulosten mukaan laidunnuksen ajoitusta, laajuutta ja laidunnuspainetta on muokattava kohdekohtaisesti, jotta saavutetaan paras tulos uhanalaisten lajien suojelun kannalta
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Larter, Nicholas C. "Diet and habitat selection of an erupting wood bison population." Thesis, University of British Columbia, 1988. http://hdl.handle.net/2429/27976.
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In this study I examine diet and habitat selection of wood bison (Bison bison athabascae) in the Mackenzie Bison Sanctuary, Northwest Territories. This reintroduced population has increased exponentially since 1963 (r=0.21), and represents the only free-ranging population in existence. A 1987 total count showed at least 1718 animals. The aims of the study were to: 1) determine changes in forage quality and forage quantity amongst the different habitats, 2) determine dietary components on a seasonal basis, 3) determine what biotic and abiotic factors affected habitat selection, and 4) determine home ranges and describe seasonal movement patterns as they relate to the changing distribution of forage.
All forages except lichen demonstrated a linear decrease in percent nitrogen concentration and a linear increase in percent indigestible fiber concentration over the growing season. Lichen had consistentent low nitrogen and indigestible fiber concentrations. The ratio of percent nitrogen concentration to percent indigestible fiber concentration (N/ADF) was used as a measure of forage quality. Phalaris arundinacea and willow were better quality forages during summer, while lichen was a better quality forage in fall. The presence of alkaloids and silicates is proposed as the reason P. arundinacea is avoided by bison. Green biomass increased until mid-July, remained high until mid-August and decreased rapidly into September. Wet sedge meadows provided three times more green biomass than willow savannas, however wet sedge meadow forage was of inferior quality and was inaccessible. Forages from willow savannas and willow-aspen habitats were of consistently superior quality until fall when forested habitats provided superior quality forage, the most important of which was lichen. Willow savannas provided the highest available crude protein of all habitats during summer and fall.
Wood bison were catholic feeders, and showed pronounced seasonal changes in diet. Sedges, especially Carex atherodes. constituted 96.1-98.8% of the winter diet. During the summer growing season the diet became a more diverse mix of sedge, grass, and willow (Salix spp.). During fall lichen (Cladina mitis) became a major dietary component representing as much as 52.1% of the diet in October. The diet was more diverse at this time of year. There was a pronounced difference between summers in the amount of sedge in the diet. During 1987 the sedge proportion dropped to 30-40% from its 1986 value of 70-90%, while the grass and willow proportions rose. Willow represented as much as 38.7% of the diet during 1987, indicating browse as a viable alternative to monocotyledonous sedges and grasses. A decreased standing crop of sedge in 1987 is proposed as a factor causing the changes in summer forage proportions. Dietary crude was higher in 1986 than 1987. Dietary crude protein levels were intermediate to the levels found in the different forages.
Forage availability was the major factor determining habitat selection. Wet sedge meadows were preferred in winter, while willow savannas were preferred in summer. The lack of habitat preference in fall corresponded with the dispersion of animals into forested habitats and the increased use of lichen for forage. Group size and weather conditions had little effect on habitat selection. Snow characteristics affected forage availability. The deeper and denser snow of the 1987-88 winter caused a shift from almost exclusive use of wet sedge meadows to use of both wet sedge meadows and willow savannas.
Home ranges were calculated using the minimum convex polygon method. Wood bison home ranges were larger than those of other North American ungulates, ranging in size from 178.5km² to 1441.9km², and far exceeded those predicted by home range-body size relationships. Females had larger home ranges than males. Median daily travel (km/day) was generally greater for females than males. Females travelled more in summer than in fall or winter. Males travelled more during pre-rut and the rut than during post-rut. Forage distribution and availability are proposed as the main determinants of large home range size. Interspecific competition for forage is proposed as a reason for larger home ranges and greater daily travel in females than males. Competition for copulations is proposed as a reason for greater daily travel by males in the pre-rut and rut.Science, Faculty of
Zoology, Department of
Graduate
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Lindsell, Jeremy A. "Ranging behaviour and habitat selection in the Scaly-breasted Illadopsis." Thesis, University of Oxford, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.393380.
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Pettett, Carly E. "Factors affecting hedgehog distribution and habitat selection in rural landscapes." Thesis, University of Oxford, 2015. https://ora.ox.ac.uk/objects/uuid:7f88e459-4d9f-4e1f-ae8e-03f000295bce.
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The UK population of hedgehogs (Erinaceus europaeus) has halved in rural areas between 2005 and 2015, and hedgehogs select urban areas over arable land. Explanations for the unsuitability of arable land for hedgehogs include: high predation risk by badgers (Meles meles), low prey densities, cold microclimates and low availability of nest sites. I investigated the reasons for hedgehog avoidance of arable land by measuring hedgehog habitat use, ranging behaviour, daily energy expenditure (DEE) and diet along a gradient of habitats from rural villages to arable farmland, under varying predation threat and temperatures. I also examined which factors affected hedgehog presence and abundance nationally. Hedgehogs preferentially selected urban habitats for both foraging and nesting, including gardens and buildings. A hedgehog's mean distance to buildings over a season was positively correlated with home range size and DEE, conceivably due to higher prey availability in rural villages and the need for increased movement on arable land to achieve sufficient food intake. I found little evidence that the prey taxa hedgehogs consumed changed along the gradient from buildings to arable land, although all hedgehogs consumed pet food, suggesting that supplementary feeding is one reason hedgehogs are attracted to buildings. On sites where badgers were present hedgehogs stayed closer to edge habitats and buildings, had smaller home ranges, spent less time on arable land, and had a lower DEE. Badger presence is one likely cause of hedgehogs' avoidance of arable land and their selection of rural villages, where badgers are found at lower densities. Nationally, badger abundance and fox (Vulpes vulpes) abundance was negatively associated with hedgehog abundance. Landowners on farms under Higher Level Stewardship (HLS) were more likely to report having seen hedgehogs than landowners on farms not under HLS. I conclude that rural villages are a key habitat for sustaining hedgehog numbers in the countryside and the connectivity between these island populations should be enhanced through the implementation of agri-environment schemes. Higher-tier schemes may also increase habitat complexity, which could potentially reduce the predation pressure from badgers, as well as enhancing hedgehogs' invertebrate food supply.
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Cao, Wei. "Coexistence of three species of desert scorpions by habitat selection." Diss., The University of Arizona, 1993. http://hdl.handle.net/10150/186545.
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Coexistence is common in nature. Two fundamental conditions must meet for competitive species to coexist. First, at least one environmental dimension must be heterogeneous enough for various species to exploit it. Second, these species must show a certain degree of intrinsic potential to differentiate along this dimension. Organisms living and partitioning in mosaic habitats are often destined to coexist. Here, I propose that habitat selection is one of the major mechanisms promoting coexistence of desert scorpions. I tested this mechanism in a three-species community (Centruroides exilicauda, Vaejovis spinigerus, and Hadrurus arizonensis) in the Tucson Mountain area. The results show (1) Density-independently selected habitats allowed the scorpions to survive but not to coexist. (2) The dynamic nature of density-dependent habitat selection ensured the scorpions coexistence in various situations. The reckless behavior demonstrated by the subordinate species (i.e. foraging in the face of danger from large species) confirmed this point. (3) Life-history characteristics, especially the body size of the scorpions, play a momentous role in positioning the scorpions on the arena of species interaction. Large scorpions always preempt the best habitats and become the dominant species. And small scorpions have to adjust their habitat preferences in deference to the large. C. exilicauda, the smallest species, is the subordinate. Its habitat use was controlled directly by the density of V. spinigerus and indirectly by the density of H. arizonensis. V. spinigerus, the most abundant species, tolerates many habitats. Its habitat use was molded by the density of H. arizonensis. Being the largest and the dominant species, the habitat use of H. arizonensis depended exclusively on its own density. Thus, the correlation of their selective behavior and density fostered the scorpions' coexistence in an ever changing desert environment.
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Bult, Tammo Peter. "Distribution and habitat use by juvenile Atlantic salmon (Salmo salar) at multiple spatial scales, and implications for habitat modelling and fish-habitat management." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/NQ47493.pdf.
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Aiken, Robin A. "Determination of habitat preferences of pronghorn (Antilocapra americana) on the rolling plains of Texas using GIS and remote sensing." Thesis, Connect to this title online, 2005. http://www.unt.edu/etd/all/May2005/Open/aiken%5Frobin%5Fa/index.htm.
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Melaschenko, Natalie Christina. "Small mammal abundance, habitat selection, and movement patterns in shrub-steppe habitat in British Columbia's Okanagan Valley." Thesis, University of British Columbia, 2010. http://hdl.handle.net/2429/19940.
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This study determines the role of vegetation in shaping individual habitat use, tortuosity of movement patterns and patterns of population density of western harvest mice (Reithrodontomys megalotis), Great Basin pocket mice (Perognathus parvus) and deer mice (Peromyscus maniculatus) in British Columbia’s Okanagan Valley. The former two mice are considered at risk in British Columbia due to loss or alteration of native habitat by human development and invasive species such as cheatgrass (Bromus tectorum). The objectives of this study were: 1) to determine the effects of cheatgrass on small mammal abundance and habitat use; 2) to use fractal analyses of path tortuosity to assess the spatial scales at which mice perceive their environment and; 3) to determine the role of vegetation and population density in shaping movement patterns. Trapping and tracking were conducted in 2008 in the Okanagan Valley of British Columbia at the northern reaches of the Great Basin ecosystem on 12 sites spanning a gradient of cheatgrass cover. Habitat use and movement patterns were delineated by powdering mice with fluorescent pigment and following their trails.
In the fall, the average population density per 1-hectare site was 18.0 ± 4.5 Great Basin pocket mice, 0.21 ± 0.08 deer mice and 0.08 ± 0.02 western harvest mice, while in the summer only Great Basin pocket mice were trapped (8.71 ± 3.20). Cheatgrass invasion ranged from 1 to 18 % cover. Cheatgrass abundance was not correlated with the population density of any small mammal species. In the summer, bare ground and shrub cover best-predicted Great Basin pocket mouse density, while in the fall bare ground alone was the best predictor. Great Basin pocket mice selected bare, open habitat. Vegetation was avoided with the exception of annual grasses, mainly comprised of cheatgrass, which Great Basin pocket mice selected. Bare ground in combination with cheatgrass may have provided optimal habitat for movement. Great Basin pocket mouse path tortuosity increased with vegetation cover and population density and decreased with open habitat. The fractal dimension of movement pathways was consistent over the spatial scales measured in this study.
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Fontaine, Alain Jacques. "Habitat selection by red-tailed hawks (Buteo jamaicensis) in prairie landscapes managed for enhanced waterfowl recruitment." Thesis, McGill University, 2002. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=29434.
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In the Canadian prairies, native grasslands have been largely replaced by an agricultural landscape with a mosaic of habitats now better described as aspen parkland. Although habitat requirements of true prairie Buteo species, Swainson's (Buteo swainsoni) and ferruginous hawks (B. regalis), are relatively well identified, little is known about habitat use by red-tailed hawks (B. jamaicensis ) in this ecoregion. This study, evaluating productivity and habitat selection of red-tailed hawks breeding in aspen parkland, was conducted on Prairie Habitat Joint Venture (PHJV) assessment sites in central Saskatchewan in 1997 and 1998. Red-tailed hawk nesting densities and productivity were determined at three sites. Home ranges were mapped. Macrohabitat use and availability data were generated from digitized aerial photographs of PHJV assessment sites using a Geographic Information system. Microhabitat variables were measured in 0.04 ha plots centered on nests and random locations. (Abstract shortened by UMI.)
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Bell, Katie. "Habitat selection and population dynamics of selected herbivores on Sondela Nature Reserve, Limpopo." Diss., University of Pretoria, 2003. http://hdl.handle.net/2263/26204.
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Please read the abstract in the section 00front of this document. Copyright 2003, University of Pretoria. All rights reserved. The copyright in this work vests in the University of Pretoria. No part of this work may be reproduced or transmitted in any form or by any means, without the prior written permission of the University of Pretoria. Please cite as follows: Bell, K 2003, Habitat selection and population dynamics of selected herbivores on Sondela Nature Reserve, Limpopo, MSc dissertation, University of Pretoria, Pretoria, viewed yymmdd < http://upetd.up.ac.za/thesis/available/etd-07112007-094017 / >Dissertation (MSc (Wildlife Management))--University of Pretoria, 2003.
Animal and Wildlife Sciences
unrestricted
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Peterson, James T. "The evaluation of a hydraulic unit-based habitat system /." free to MU campus, to others for purchase, 1996. http://wwwlib.umi.com/cr/mo/fullcit?p9821340.
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Bilbao, Joshua Vicente. "Predicting feeding site selection of mule deer on foothill and mountain rangelands." Thesis, Montana State University, 2008. http://etd.lib.montana.edu/etd/2008/bilbao/BilbaoJ1208.pdf.
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Determining areas on the landscape selected by mule deer (Odocoileus hemionus) for foraging and the characteristics of selected feeding sites is a crucial step in managing mule deer and its habitat. Mule deer populations in much of western North America have been declining since the early 1990\'s, making management of mule deer increasingly difficult. Limited research has examined the characteristics of mule deer habitat that influence feeding site selection in foothill and mountain rangeland habitats during the winter and spring. The purpose of the study was to develop and validate models that incorporate the effects of important habitat variables that influence feeding sites chosen by mule deer in the winter and spring, including aspect, distance to forested cover, distance to hiding cover, distance to agricultural fields, distance to improved roads, distance to ranch roads, elevation, previous cattle grazing, and slope. Data collected in northwestern Wyoming between the summer of 1999 and spring of 2001 were used for model development, and data collected between summer 2001 and spring 2003 were used for temporal validation. Additionally, data collected in west-central Montana between summer 2001 and spring 2003 were used for temporospatial validation. Logistic regression was used to develop models for the winter, spring, and winter-spring seasons. Akaike\'s Information Criterion was used to determine the best models for each season. Models were validated on both a temporal and temporospatial scale. Six habitat variables (distance to improved roads, distance to ranch roads, distance to security cover, aspect, slope, and previous summer\'s cattle grazing) were included in model development after collinearity tests. Four models had a model sensitivity > or equal to 75% in both temporal and temporospatial validation. These models can be used to identify preferred mule deer feeding sites and assess potential impacts of land management practices on mule deer foraging habitat.
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Cheng, Yi-Ru. "Differential growth of body components among coexisting passerine species in response to nest predation risk." CONNECT TO THIS TITLE ONLINE, 2008. http://etd.lib.umt.edu/theses/available/etd-01132009-180702/.
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Larson, Kyle Blake. "Nest habitat selection of burrowing owls in relation to soils, burrow availability, and burrow temperature." Pullman, Wash. : Washington State University, 2009. http://www.dissertations.wsu.edu/Thesis/Summer2009/K_Larson_072409.pdf.
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Thesis (M.S. in environmental science)--Washington State University, August 2009.Title from PDF title page (viewed on Sept. 17, 2009). "School of Earth and Environmental Sciences." Includes bibliographical references (p. 35-42).
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Graf, Astrid. "Influencing habitat selection and use through conspecific attraction and supplementary feeding." Diss., Lincoln University, 2008. http://hdl.handle.net/10182/1061.
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Bellbirds (Anthornis melanura) are one of two endemic honeyeaters in New Zealand. They are still common in many parts of the country, but also rare and absent in some areas where they were abundant before. Together with tui (Prosthemadera novaeseelandia) bellbirds are responsible for avian pollination of several native plants in New Zealand. Habitat fragmentation and geographical constraints prevent bellbirds from re-occupying formerly inhabited areas. After translocations birds often disperse; some just disappear, some are thought to fly back to their source site and probably many die. Supplementary feeding provides energy rich food, which helps to ensure birds are well-nourished until they can discover natural food sources at the release sites. Conspecific song playback as an attractant for many bird species can be used as public information about high habitat value and additionally lure birds to good food sources and nest sites. Artificial feeding stations were set up at 18 locations in Kennedy's Bush, Port Hills, Canterbury, New Zealand. Feeders filled with sugar water were available for five to six consecutive days and during observation hours the effect of song playback was tested. Variation in bird numbers resulting from experimental treatments was recorded using five-minute bird counts prior to treatments and additional counts every minute of observation time. Bellbird numbers varied strongly with habitat types, showing highest numbers for dense and tall bush areas and close to creeks and lowest for open areas besides pasture and in post-flowering flax fields. Bellbird numbers increased when song was broadcast, with the strongest effect in areas where bellbird numbers were moderate or low, but not in areas where bellbirds were absent. Feeding stations were not observed to be used by bellbirds. The strong response in bellbird numbers to conspecific song playback proved the attractiveness of song for bellbirds. Nevertheless, its function as a lure for bellbirds to artificial feeding stations was not shown. This contrasting result indicates that the use of bellbird song as an enticement for bellbirds has to be investigated further.
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Hall, Anna Marie. "Foraging behaviour and reproductive season habitat selection of northeast pacific porpoises." Thesis, University of British Columbia, 2011. http://hdl.handle.net/2429/37218.
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Behavioural observations are fundamental to understanding and defining the habitat needs of animals. I compiled the behavioural repertoires reported for harbour (Phocoena phocoena) and Dall’s porpoise (Phocoenoides dalli) by classifying the life processes of phocoenids into 12 descriptive categories. This range-wide review revealed complex sexual and social behaviours, similar foraging behaviours and breeding site fidelity, as well as differences in habitat selection between these two northern hemisphere species. I also conducted a fine-scale field study of harbour porpoise foraging behaviour at two sites in Juan de Fuca Strait (British Columbia) using point transect survey data (2007–2008), and platforms of opportunity data (1995–1996, 1998–2008) to determine the physical conditions under which harbour porpoise foraged and the extent to which they displayed specialised behaviours. I examined harbour porpoise presence, density and group sizes relative to tidal currents, tidal variation, lunar phase, lunar position, solar position, diurnality, seasonality and presence of conspecifics—and found that greater numbers of harbour porpoise occurred on the ebb current during the spring tides. Numbers of porpoise increased three-fold between April and October, when calves and high-energy behaviours were also more prevalent. To identify porpoise breeding habitat in the inland waters of southern British Columbia and northwestern Washington, I used systematically and opportunistically collected sightings of harbour and Dall’s porpoise (1991–2008), and compared group sizes and frequency of occurrences for both species relative to bathymetry and tidal speeds. Overall, I found that both species selected bathymetrically differentiated habitats that were characterized by high rates of tidal mixing (with harbour porpoise preferring regions ≤100 m, and Dall’s porpoise preferring 151 – 250 m). Spatial analysis identified two separate areas that may be species-specific breeding habitats—the first to be identified for either species in this region. In summary, harbour porpoise maintained stable group sizes and used tidally well-mixed foraging sites on a temporary but predictable basis. Dall’s porpoise were associated with these same areas, but habitat partitioning associated with differences in bathymetry occurred in important breeding areas that may account for the coastal parapatric distribution of these two high trophic level predators.
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Basile, Cynthia. "Relative abundance and habitat selection by Cerulean warblers in southern Indiana." Virtual Press, 2002. http://liblink.bsu.edu/uhtbin/catkey/1236576.
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Weinman, Michelle L. "Grass pickerel diet and habitat selection in Indiana rivers and streams." Virtual Press, 2006. http://liblink.bsu.edu/uhtbin/catkey/1356256.
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Grass pickerel were collected in rivers and streams throughout Indiana for diet analysis. Frequency of occurrence, mean percent volume, and relative importance index were calculated for diet from all grass pickerel stomachs containing food. Grass pickerel were divided into three size classes (57-95mm, 96-150mm, >150mm) and stomach contents were divided into four groups (insects, fish, crayfish, and other). Grass pickerel in the small size class consumed mostly fish and crayfish while in the largest size class mostly crayfish were ingested. In addition, habitat selection was identified for grass pickerel. Macro and microhabitat were evaluated and described using the Qualitative Habitat Evaluation Index and visual assessment. Grass pickerel selected habitat with slow moving water and instream cover of either logs/woody debris or aquatic macrophytes.Department of Biology
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Lautenbach, Joseph Mark. "Lesser prairie-chicken reproductive success, habitat selection, and response to trees." Thesis, Kansas State University, 2014. http://hdl.handle.net/2097/18810.
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Master of ScienceDepartment of Biology
David A. Haukos
The lesser prairie-chicken (Tympanuchus pallidicinctus) is a species of prairie grouse native to the southwest Great Plains. Population declines and threats to populations of lesser prairie-chickens led U.S. Fish and Wildlife Service to list the species as “threatened” under the protection of the Endangered Species Act in May 2014. Lesser prairie-chickens are found within three distinct ecoregions of Kansas and Colorado and portions of the species’ range are affected by tree encroachment into grasslands. The effect of trees on lesser prairie-chickens is poorly understood. I evaluated habitat selection and reproductive success and across the northern portion of the species’ range. I captured female lesser prairie-chickens within the three different ecoregions in Kansas and Colorado to track nest and brood survival and measure nest and brood habitat. My findings show that there are regional and annual variations in nest and brood survival. Mean nest survival during 2013 and 2014 was estimated to be 0.388 (95% CI = 0.343 – 0.433) for a 35-day exposure period. Brood survival during 2013 and 2014 was estimated to be 0.316 (95% CI = 0.184 – 0.457) for 56 days. Chick survival was the lowest during the first week of life and is probably a limiting factor for population growth. Chick and brood survival decreased as Julian hatch date increased. Across the northern portion of the species’ range, females consistently select visual obstruction between 2-3 dm. Vegetation at the nest changes between regions and years to reflect environmental and regional conditions. Broods consistently selected habitats with greater percent cover of forbs than was expected at random across all study sites. Broods also selected against areas of bare ground. The threshold of lesser prairie-chicken use was 2 trees/ha throughout the year. No nests were located within areas with greater densities. Lesser prairie-chickens had a greater probability of use at greater distances from trees and at lower tree densities. To provide adequate nesting habitat managers should provide 2-3 dm of visual obstruction. Providing forb cover with visual obstruction between 2.5-5 dm near nesting habitat should provide adequate habitat for broods. Removing trees in core habitats and expand removal efforts outward should expand potential habitat for lesser prairie-chickens.
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Champneys, A. "Factors affecting distribution and habitat selection of water shrews Neomys fodiens." Thesis, Nottingham Trent University, 2012. http://irep.ntu.ac.uk/id/eprint/100/.
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The water shrew Neomys fodiens is one of Britain’s least known mammals and its habitat requirements are poorly understood. The purpose of this study was to determine occurrence and associated habitat preferences of water shrews, a species of conservation concern, by comparing populations in central England freshwater habitats. Bait tube surveys were undertaken at 32 freshwater sites to establish water shrew presence, half of which were found to contain water shrews. Habitat surveys were undertaken and, in addition to water shrew presence/absence data, were used to develop habitat suitability index models by means of artificial neural networks. Management intensity (occasional or frequent bankside management) was identified as the most important predictor of water shrew presence and, when combined with dissolved oxygen (0-2.99mg l-1) and water depth (<25cm), created the highest performing model. These models will allow sites to be rapidly assessed for water shrew presence without labour intensive and costly live-trapping techniques. Prey availability was investigated by undertaking invertebrate surveys at four water shrew-positive sites, as well as at an additional four sites with unknown water shrew presence with which to compare. Overall, there was no significant difference between the total numbers of terrestrial and aquatic invertebrates at sites with known/unknown water shrew presence although there were differences in composition of potential prey. POPAN abundance of water shrews was estimated, and its relationship with other small mammal species investigated, using live trapping at the four water shrew positive sites. Negative relationships were found between water shrews and the terrestrial shrew species although these were not significant. Individually identifying captured water shrews using traditional fur-clipping marking methods is difficult. Therefore, buccal swab samples were taken to identify individuals via genetic profiling. Determining numbers of water shrews via genetic profiling was found to be more accurate than through fur-clipping which overestimated populations. Furthermore, buccal swab sampling is a new, minimally invasive method of identifying individuals which can be used to give accurate information about water shrew population densities and dynamics across seasons. This is the first in-depth study of factors affecting the occurrence and habitat selection of water shrews in central England and has made some important contributions to the understanding of habitat analysis and species identification.
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Becker, Scott. "Habitat selection, condition, and survival of Shiras moose in northwest Wyoming." Laramie, Wyo. : University of Wyoming, 2008. http://proquest.umi.com/pqdweb?did=1799711361&sid=1&Fmt=2&clientId=18949&RQT=309&VName=PQD.
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Hall, Linnea Suzanne. "Habitat selection by the elegant trogon (Trogon elegans) at multiple scales." Diss., The University of Arizona, 1996. http://hdl.handle.net/10150/187497.
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In this dissertation I discuss several facets of the ecology of the elegant trogon (Trogon elegans). In Chapter 1, I assessed habitat selection by the trogon from 1993 to 1995 at three spatial scales (those of the mountain and canyon, home range, and microsite scales). At the broadest (inter-mountain and inter-canyon) scale, trogons were positively associated with cover by sycamore, pinyon, and juniper vegetation, and the abundances of three bird species. At the intermediate scale, radio-tagged trogons in the Huachuca and Santa Rita mountains used both upland and riparian areas, and selectively used sites with dense vegetation within those areas. At the microsite scale, nest sites of trogons were primarily located in sycamore trees in riparian areas. Successful nests could be discriminated from unsuccessful nests on the basis of three variables. Adult trogons used trees that were mostly dead for several behaviors besides nesting, and males foraged from sycamore and oak trees. Across all three scales, trogons were associated with variables describing sycamores, junipers, pines, and oaks, indicating that these trees were important to elegant trogon habitat use in Arizona. In Chapter 2, I discussed the behavior and phenology of nesting elegant trogons in the Chiricahua, Huachuca, and Santa Rita mountains in 1993-1994. I described the average durations and characteristics of nest advertisement, incubation, brooding, nestling attendance, and fledgling attendance behaviors. Elegant trogons in Arizona had different behaviors from other members of Neotropical Trogonidae, especially in regards to their durations of incubation and feeding. In Chapter 3, I present analyses of disturbance records collected while observing trogons in 1993-1995, and the finding that elegant trogons did not react strongly to most contacts with humans. However, on some occasions trogons reacted long enough to humans to potentially impact their productivity at nest sites. Therefore, some protection of nesting trogons may be warranted. In general, management of trogons in Arizona will require consideration of whole watersheds, including the condition of riparian water tables and upland vegetation.
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Dodd, Jane. "Topographic learning and memory in habitat selection by Lipophrys pholis L." Thesis, Bangor University, 1998. https://research.bangor.ac.uk/portal/en/theses/topographic-learning-and-memory-in-habitat-selection-by-lipophrys-pholis-l(65cf5889-e075-4b3b-a268-06e3484ce380).html.
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Experiments were carried out to test the ability of L. pholis to learn and remember the position of a food reward in a hierarchical maze during daily trials. This task was completed in 9 days in the presence of LegoTM landmarks. Learning did not take place in the presence of a white screen clue or in the absence of any obvious visual clues after 15 days. An attempt was made to identify the effect of a change in conditions on L. pholis who had already learned to successfully navigate the hierarchical maze, and to identify the clues utilised in learning, by altering the intra and extramaze clues. Geomagnetic, olfactory / gustatory and current direction clues were eliminated as the source of spatial information, as was the use of a cognitive map (Tolman 1948, O'Keefe & Nadel 1978). Rather, evidence suggested that the fish were learning a specific route through the hierarchical maze using the LegoTM towers as beacons, and as a prompt as to which direction to turn at important stages in the journey. This memory was retained for a period of at least 30 days. A hierarchy of clue use was suggested by the fact that the subjects used the direction of entry to the experimental arena, or the direction by which the experimenter left the arena just prior to a daily test, as a directional clue to the position of the reward box in the absence of Lego towers. These experiments suggested that in the wild L. pholis uses the position of local landmarks, such as rocks and clumps of algae, to direct movements towards feeding patches. A study of behaviour of L. pholis placed in a novel artificial habitat was also carried out. L. pholis moved along the edges of the objects placed in the arena, followed regularly used paths between refuges, and explored the arena from a series of "base" refuges. In the more active individuals, each refuge was investigated until the subject took up residence in a preferred refuge. This adopted shelter was often centrally placed and commanded a good view of a large area of the arena. Activity was concentrated in the more complex half of the arena and experienced fish directed their movement towards this area 24 hours after 6 hours exploration of the novel habitat. There was also evidence to suggest that certain individuals learned the position of a specific preferred refuge after the 6 hour exploratory period. Finally, the ability of L. pholis to remember the position of a refuge was tested in an artificial habitat under the influence of different clues. L. pholis learned the position of the refuge in the presence of an A4 sized black screen clue only. They responded to this clue by moving towards it and pressing themselves up against it while LegoTM towers and a white screen clue did not provoke such a response. L. pholis continued to respond to the black screen in this way even when it was moved to another location further from the refuge. After 12 days L. pholis learned to use the black screen as an indirect clue and navigate to the refuge directly without first touching it. These results suggested that when placed in a novel habitat the immediate reaction of L. pholis is to move quickly towards the first dark area they see. Later, they systematically explore all available shelters and choose a preferred one according to complexity of the surrounding habitat. With experience, they can use the position of objects around them to navigate quickly and efficiently to their preferred refuge or the nearest suitable refuge depending on the severity of the threat.
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Peck, Riley D. "Seasonal Habitat Selection by Greater Sage Grouse in Strawberry Valley Utah." BYU ScholarsArchive, 2011. https://scholarsarchive.byu.edu/etd/3180.
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This study examined winter habitat use and nesting ecology of greater sage grouse (Centrocercus urophasianus) in Strawberry Valley (SV), Utah located in the north-central part of the state. We monitored sage grouse with the aid of radio telemetry throughout the year, but specifically used information from the winter and nesting periods for this study. Our study provided evidence that sage grouse show fidelity to nesting areas in subsequent years regardless of nest success. We found only 57% of our nests located within the 3 km distance from an active lek typically used to delineate critical nesting habitat. We suggest a more conservative distance of 10 km for our study area. Whenever possible, we urge consideration of nest-area fidelity in conservation planning across the range of greater sage grouse. We also evaluated winter-habitat selection at multiple spatial scales. Sage grouse in our study area selected gradual slopes with high amounts of sagebrush exposed above the snow. We produced a map that identified suitable winter habitat for sage grouse in our study area. This map highlighted core areas that should be conserved and will provide a basis for management decisions affecting Strawberry Valley, Utah.
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Edgel, Robert John. "Habitat Selection and Response to Disturbance by Pygmy Rabbits in Utah." BYU ScholarsArchive, 2013. https://scholarsarchive.byu.edu/etd/3928.
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The pygmy rabbit (Brachylagus idahoensis) is a sagebrush (Artemisia sp.) obligate that depends on sagebrush habitats for food and cover throughout its life cycle. Invasive species, frequent fires, overgrazing, conversion of land to agriculture, energy development, and many other factors have contributed to recent declines in both quantity and quality of sagebrush-steppe habitats required by pygmy rabbits. Because of the many threats to these habitats and the believed decline of pygmy rabbit populations, there is a need to further understand habitat requirements for this species and how they respond to disturbance. This study evaluated habitat selection by pygmy rabbits in Utah and assessed response of this small lagomorph to construction of a large-scale pipeline (i.e. Ruby pipeline) in Utah. We collected habitat data across Utah at occupied sites (pygmy rabbit occupied burrows) and compared these data to similar measurements at unoccupied sites (random locations within sagebrush habitat where pygmy rabbits were not observed). Variables such as horizontal obscurity, elevation, percent understory composed of sagebrush and other shrubs, and sagebrush decadence best described between occupied (active burrow) and unoccupied (randomly selected) sites. Occupied sites had greater amounts of horizontal obscurity, were located at higher elevations, had greater percentage of understory comprised of sagebrush and shrubs, and had less decadent sagebrush. When considering habitat alterations or management these variables should be considered to enhance and protect existing habitat for pygmy rabbits. The Ruby pipeline was a large-scale pipeline project that required the removal of vegetation and the excavation of soil in a continuous linear path for the length of the pipeline. The area that was disturbed is referred to as the right of way (ROW). From our assessment of pygmy rabbit response to construction of the Ruby pipeline, we found evidence for habitat loss and fragmentation as a result of this disturbance. The size of pygmy rabbit space-use areas and home ranges decreased post construction, rabbits shifted core-use areas away from the ROW, and there were fewer movements of collared rabbits across the ROW. Mitigation efforts should consider any action which may reduce restoration time and facilitate movements of rabbits across disturbed areas.
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Schumaker, Nathan H. "Habitat connectivity and spotted owl population dynamics /." Thesis, Connect to this title online; UW restricted, 1995. http://hdl.handle.net/1773/5524.
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Jansson, Camilla. "Habitat selection and oviposition of the endangered butterfly Scolitantides orion in Sweden." Thesis, Linköpings universitet, Institutionen för fysik, kemi och biologi, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-94649.
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Detailed knowledge about the habitat requirements of butterflies is vital for successful conservation. The aim of the present study was to examine the habitat requirements of the endangered butterfly Scolitantides orion on 15 sites in Östergötland, Sweden. The requirements of adults and ovipositing females were studied with regard to several environmental variables measured at three scales; small, transect and large scale. The probability of finding adults increased with decreasing tree cover at the small scale, and adult numbers increased with the proportion of bare rock at the large scale. In contrast, ovipositing females mainly responded to the small scale. The main finding was that females oviposited in areas with higher tree cover (< 70 %) than that preferred by dwelling adults (< 20 %). However, there was a greater probability of finding eggs when tree cover was less than 50 %. Furthermore, egg numbers on host plants increased with the number of leaves on the stem and with the proportion of surrounding bare rock or bare ground. At the transect scale, females oviposited in areas with a higher density of host plants. To conclude, S. orion predominately inhabits open areas with warm microclimatic conditions for dwelling and oviposition. To conserve this species, suitable areas containing nectar plants and high densities of host plants with large leaf numbers and surrounded by large proportions of bare rock or bare ground, should be preserved. The areas should be maintained by selective clearing at regular intervals to uphold canopy openness and heterogeneity.
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Figueroa, Omar Antonio. "Nesting habitat selection and habitat associations of juvenile Jabiru storks (Jabiru mycteria) in Belize, Central America implications for conservation /." [Gainesville, Fla.] : University of Florida, 2005. http://purl.fcla.edu/fcla/etd/UFE0012000.
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Frey, Sarah. "Metapopulation Dynamics and Multi-Scale Habitat Selection of a Montane Forest Songbird." ScholarWorks @ UVM, 2008. http://scholarworks.uvm.edu/graddis/86.
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Variations in species occurrence and distribution across the landscape over time provide fundamental information concerning population dynamics. How this relates to habitat characteristics at multiple scales can elucidate the process of habitat selection. I evaluated these processes for a montane fir (Abies) forest specialist, Bicknell’s Thrush (Catharus bicknelli) in Vermont. This species is threatened by a suite of anthropogenic disturbances on its breeding grounds and quantifying the effects of environmental change at the population level for this songbird has not been addressed. The naturally fragmented breeding habitat of varying size, quality, and connectivity warranted a metapopulation approach and a robust occupancy analysis. Detection/non-detection data was collected for Bicknell’s Thrush across 88 sites during the breeding seasons in 2006 and 2007. Local habitat characteristics were measured for each site and landscape-level features were calculated using a predictive habitat model. The six local habitat variables were combined using a principal component analysis. Principal component 1 (PC1) described a gradient of increasing coniferous shrub density and proportion of coniferous dominated forest with decreasing canopy height. The landscape covariate was calculated by dividing patch size by patch isolation creating a continuum of small, isolated patches to large, less isolated patches. Thus each site was characterized by a single local habitat (PC1) and landscape metric. From these data, 67 models considering all combinations of landscape and local habitat scores (univariate, additive and interaction) were evaluated for individual estimates of the following parameters: (1) probability of detection, (2) probability of initial site occupancy, (3) probability of site colonization, and (4) probability of local site extinction. AIC model selection techniques were used to rank the models, which represented ecologically plausible hypotheses that compared the strength of local habitat characteristics to large-scale landscape features. Models within 4 AICc points of the top model were considered plausible. The top eight models were all plausible. Landscape characteristics alone were not significant in driving population dynamics. The relative importance of landscape + local habitat was highest for both probability of initial occupancy and local site extinction. Probability of occupancy increased and extinction decreased with the combination of increased patch size and decreased patch isolation (landscape) and increased coniferous shrub density, proportion of coniferous dominated forest and decreased canopy height (local habitat). Probability of site colonization was driven mainly by local habitat features and increased with increasing habitat quality. These results indicate a complex system with intricate links between landscape and local scales. Preserving large tracts of habitat may not be sufficient in assuring future species persistence, but could minimize local extinction risk. Careful consideration should be given to local habitat features within habitat fragments, particularly to maintain adequate colonization rates. Because important features from both scales are correlated, in intact montane forest patches, landscape-scale attributes alone may serve as a surrogate for identifying quality breeding habitat, assuming processes of natural disturbance can be maintained.
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Stanek, John R. "Breeding habitat selection by rosy-finches in the San Juan Mountains, Colorado." Laramie, Wyo. : University of Wyoming, 2009. http://proquest.umi.com/pqdweb?did=1939351891&sid=1&Fmt=2&clientId=18949&RQT=309&VName=PQD.
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Hewitson, Stacy. "Habitat selection by breeding American black ducks (Anas rubripes) in northeastern Nova Scotia." Thesis, McGill University, 1994. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=22739.
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Habitat selection by breeding black ducks (Anas rubripes) was studied in Antigonish County, Nova Scotia during April-September 1990 and 1991.Black duck pairs selected deciduous shrub ponds and sparsely vegetated ponds and avoided estuarine marsh and large lake habitat. Hens with broods preferred the deciduous shrub habitat while they avoided large lakes.
Black duck pairs appeared to use the distance to a brood-rearing pond as a cue in site selection. The closer a pond was to a suitable rearing pond the more likely it was occupied by a pair, regardless of food or cover resource availability. Black ducks, however, likely used site attributes such as the perimeter of the pond, the availability of aquatic invertebrates and the relative abundance of alder, willow and dead timber as cues in the selection brood-rearing habitat.
Black duck duckling survival, an estimate of recruitment, was the highest on preferred deciduous shrub ponds. Duckling survival was also higher on ponds with only one brood as opposed to ponds with several broods.
The most productive habitat for black ducks in the Antigonish study area were isolated, deciduous shrub ponds influenced by beaver activity. Black duck population numbers can be enhanced by managing local beaver populations.
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Baum, Elizabeth M. "Monitoring Domestic Sheep Energy Requirements and Habitat Selection on Summer Mountain Range Using Low-Cost GPS Collar Technology." BYU ScholarsArchive, 2021. https://scholarsarchive.byu.edu/etd/9177.
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With the advent of global position system (GPS) collar technology, we have developed a much greater understanding of the temporal and spatial distribution of livestock and their associated grazing patterns. While significant research using GPS collars has been reported for cattle, little research is available describing collar use in understanding the behavior of domestic sheep. The purpose of our research was to evaluate the energy requirements of sheep with the use of GPS collars. To accomplish this, we adapted a low-cost i-gotU GPS tracking device that is typically designed for cattle and modified it to fit sheep. Each collar was programmed to record sheep movements within four grazing habitat types during different times of the year. Habitat types included spring pasture (SP), spring low hill habitat (SH), summer mountain habitat (MH) and winter desert habitat (DH). We divided our research into two studies: 1) to track and compare energy expenditure of domestic sheep between four habitats using collars for recording sheep movements, and 2) to model summer mountain selection by sheep using the collar derived coordinate positions and environmental variables in an RSF model process. We hypothesized that there would more energy expended while out on desert habitat in comparison to other range habitats and sheep would select for sites on summer mountain habitat that were close to water, gentle in terrain, and higher in elevation. We used sheep energy equations to determine the energy requirement. Collar derived coordinates were used to measure the horizontal distance traveled on flat terrain or vertical distances both upslope and downhill across variable terrain. Our results found that total distance traveled was not different between SP, SH and MH at 6.7, 7.1 and 6.9 km/d, respectively, however, total movement was different (P<0.05) on DH at 10.5 km/d. Sheep movement was greater (P<0.05) on slopes (altitude change in 3m between waypoints) versus flat terrain (movement between waypoints >20m). For example, sheep spent 65% of movement on slope and 39% on flat movement for SH, 86% of movement was spent on slope and 16% on flat terrain for MH, and 89% of movement was spent on slope and 11% movement was on flat for DH. Total energy required between the four habitats was different (P<0.05) at 5.9, 8.6, 7.1 and 13.9 Mcal ME/d for SP, SH, MH and DH respectively. While on summer MH sheep avoided slopes and rugged terrain, but selected for sites close to water, northern facing aspects and areas higher in elevation. We found that sheep expend the most energy on DH and sheep on MH will select for gentle terrain, areas close to water, northern facing slopes, higher elevation and avoid slopes. With this insight, sheep managers can better meet energy requirements needs and understand habitat utilization of their flocks.
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Wolfe, Scott Adrian. "Habitat selection by calving caribou of the central arctic herd, 1980-95." PURL, 2000. http://www.arlis.org/docs/vol1/76789631.pdf.
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