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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Reintroduction biology of yellow-footed rock wallabies (petrogale xanthopus celeris and P. x. xanthopus

Lapidge, Steven James January 2002 (has links)
Based on the recommendations of both the 1993 Reintroduction biology of Australasian Fauna Conference and the 1994 Rock Wallaby Symposium, captive-bred Yellow footed rock wallabies were reintroduced into areas of their former ranges in both South Australia and Queensland
22

The effects of release techniques on the reproductive performance and post-fledging juvenile survival of captive-bred Western Burrowing Owls (Athene cunicularia hypugaea) in the Nicola Valley, British Columbia

Mitchell, Aimee Marie 05 1900 (has links)
Reintroduction of captive-bred Western Burrowing Owls (Athene cunicularia hypugaea) in the Nicola Valley, British Columbia, has had limited success in increasing the local breeding population. Traditionally, yearling captive-hatched Burrowing Owls that were paired and released into artificial burrows in the field, held overnight, and provided with supplemental food throughout the breeding season (hard release) have had high post-release dispersal and mortality. In 2005 and 2006, I used an alternative soft-release technique to test for an improvement upon the hard-release technique. The soft release followed the same procedure as the traditional hard release but also included enclosures around burrow entrances to contain the owls for a 2-week period in the field prior to release. I compared immediate post-release dispersal, seasonal survival, and reproductive success for 37 hard-released and 30 soft-released pairs. I radio-tagged 39 of these released owls in order to accurately monitor their activities, regardless of whether they remained at release sites or dispersed. The soft-release technique led to 20% more owls remaining at the release sites, 14% more owls surviving the breeding season, and 20% more owl pairs fledging juveniles. In addition to investigating adult survival and reproductive success, I examined post-fledging juvenile survival, local recruitment, and habitat use, and adult prey consumption behaviour in order to assess the potential of these aspects to limit the success of the reintroduction. Survival and local recruitment rates of the juveniles of captive-bred adults released with two different techniques were similar to that of juveniles of wild adults in the same study area or in other parts of the Burrowing Owl's range. Juvenile habitat-selection analyses identified the importance of rangeland, and comparisons of prey consumption revealed the rapid development of foraging abilities by captive-bred Burrowing Owls. I concluded that these aspects of the owl's ecology were not negatively affected by a captive upbringing, and therefore not likely limiting the success of the reintroduction. Overall, the use of an enclosure-based soft-release technique addresses major limitations to the success of releases, and shows promise for increasing the breeding population in this region. This approach can also be applied to recovery efforts throughout the Burrowing Owls' range, and provide guidelines for other species' reintroduction programs.
23

Leadership and Management of Wildlife Reintroduction Programs

Sutton, Alexandra E. 2009 August 1900 (has links)
Wildlife reintroduction programs are a type of conservation initiative meant to preserve biodiversity through the restoration of damaged areas and the reintroduction of extirpated species. Unfortunately, such reintroductions have a history of limited success, ad hoc procedures, and little focus on hypothetico-deductive design. This study sought to identify some of the trends in the leadership, management, and structure of wildlife reintroduction programs through the use of a case study and survey. The survey was distributed to reintroduction practitioners and biologists worldwide in an attempt to identify patterns of organizational behavior within the field. Some general trends indicated that most reintroductions had active and monitoring phases of 4 or more years (59% and 75% of respondents respectively), adhered closely to World Conservation Union (IUCN) Reintroduction Guidelines (43% of respondents), had a somewhat hierarchical structure (50% of respondents), held annual long-term goal-setting meetings (56%), observed annual employee evaluations (63%), and underwent project evaluations annually, using both internal (74%) and external (39%) evaluative instruments. Opinion questions regarding the ultimate performance of the project indicated that although 75% of researchers felt that their project had made good progress, only 63% said that a formal evaluation had confirmed this statement.
24

THE INTRODUCTION OF NATIVE FOREST FLOOR PLANT SPECIES INTO THE INDUSTRIALLY DISTURBED FORESTS OF SUDBURY, ONTARIO, CANADA

Santala, Kierann R. 17 March 2014 (has links)
This study investigated the transplantation of understory plants within the Cu-Ni smelterdamaged urban forest of Sudbury, Ontario, Canada, to increase plant biodiversity in an area where natural colonization of understory species is delayed. The goal of my study was to evaluate establishment of 16 m2 vegetation mats along a gradient of smelter disturbance and to relate successful establishment to abiotic and biotic site characteristics. Specific investigations were conducted to determine whether soil quality influenced root growth and transplant establishment. Variables associated with smelter emissions and soil temperature were the best predictors of successful transplant establishment of understory plant species, but relationships were species specific. Also, root growth was not limited to organic soils of the transplant mat and roots were able to grow into receptor site soil. Knowledge of environmental factors influencing establishment will help to determine site locations and to select species to introduce when transplanting understory species in future reclamation projects.
25

A Metapopulation Approach to Recovery of the Five-Lined Skink Using Rehabilitated Aggregate Extraction Sites

Cameron, Melissa 03 March 2009 (has links)
Protecting existing habitat for species-at-risk is an important conservation measure; however, many populations occupy highly fragmented habitat patches to the extent that population persistence is unlikely without the creation of new habitat patches. This research examines the potential for clusters of rehabilitated aggregate extraction sites to be used as reintroduction sites for species-at-risk. Using a method combining GIS and metapopulation modeling, I evaluated the success of establishing metapopulations of the Five-Lined Skink, Eumeces fasciatus, in 137 clusters of aggregate extraction sites using three hypothetical recovery scenarios. Patch abundance and patch clustering had a significant negative effect on metapopulation extinction risk. Increasing the quality of a single patch relative to other patches of suitable quality had little effect on extinction risk and patch occupancy. Introducing all individuals into a single patch decreased extinction risk and patch occupancy. Rehabilitated aggregate sites could play a role in the protection of species-at-risk in Ontario.
26

STATUS OF A REINTRODUCED BLACK BEAR POPULATION IN THE BIG SOUTH FORK AREA OF KENTUCKY

Murphy, Sean McCarthy 01 January 2011 (has links)
Large carnivores have been subjected to overexploitation and extensive habitat loss for centuries. Reintroduction has become an increasingly used tool for recovering and reestablishing large carnivore populations; however, most reintroductions have either failed or resulted in small populations that are vulnerable to deleterious demographic, environmental, and genetic effects that can lead to population loss or extinction. Longterm monitoring of small, reintroduced populations is critical to population persistence and viability. To evaluate long-term reintroduction success and current status of a recently reintroduced, small black bear (Ursus americanus) population in the Big South Fork area of Kentucky, I used non-invasive hair sampling in a systematic, closedpopulation capture-mark-recapture study design. I used ≥ 20 microsatellite loci to identify individual bear, quantify genetic diversity, investigate genetic relatedness, estimate population abundance and density, and investigate patterns of range expansion. The Big South Fork population is comprised of closely-related individuals, is small (N = 40; 95% CI: 30-113), of low density (0.03 bear/km2), has experienced minimal range expansion, and exhibits decreased genetic diversity (HE = 0.698). Because of prolonged isolation from nearby subpopulations, the Big South Fork population remains vulnerable and requires immediate and continued monitoring.
27

Reintroduction biology of yellow-footed rock wallabies (petrogale xanthopus celeris and P. x. xanthopus

Lapidge, Steven James January 2002 (has links)
Based on the recommendations of both the 1993 Reintroduction biology of Australasian Fauna Conference and the 1994 Rock Wallaby Symposium, captive-bred Yellow footed rock wallabies were reintroduced into areas of their former ranges in both South Australia and Queensland
28

Grizzly bear reintroduction understanding stakeholder interests in the Selway-Bitterroot ecosystem south of the Salmon River /

Teevin, Colleen Elizabeth. January 2008 (has links) (PDF)
Thesis (M.S.) --University of Montana, 2008. / Title from author supplied metadata. Description based on contents viewed on May 15, 2009. ETD number: etd-12302008-135445. Author supplied keywords: Grizzly ; stakeholder ; Idaho ; Bitterroot ; reintroduction. Includes bibliographical references.
29

The rewilding of New York's north country beavers, moose, canines and the Adirondacks /

Aagaard, Peter Miles. January 2008 (has links)
Thesis (M.A.)--University of Montana, 2008. / Title from title screen. Description based on contents viewed Aug. 7, 2008. Includes bibliographical references (p. 110-123).
30

Tamanho populacional, razão sexual e uso do habitat por uma população de mutum-do-sudeste (Crax blumenbachii Spix, 1825) reintroduzida em Ipaba, MG / Population size, sex ratio and habitat use of a Red-billed Curassow (Crax blumenbachii Spix, 1825) population reintroduced in Ipaba, MG, Brazil

Joana Carvalhaes Borba de Araujo 25 September 2015 (has links)
A fragmentação e a redução do habitat são as principais causas do declínio populacional e de biodiversidade no mundo, seguidas pela sobrecaça. Essas perturbações levaram a família Cracidae ao posto de família de aves mais ameaçada das Américas. Diversos programas de reintrodução já foram conduzidos com cracídeos no Brasil, a começar pela reintrodução do mutum-do-sudeste (Crax blumenbachii Spix, 1825) na Fazenda Macedônia (FM) em Ipaba, MG. O objetivo deste trabalho foi estimar o tamanho e a densidade populacional e a razão sexual dos mutuns existentes na FM e analisar o uso da paisagem pela espécie. Os dados foram coletados ao longo de 6 meses por transecção linear (esforço amostral: 280 km) e analisados segundo protocolos de amostragem por distância linear e ocupação. O tamanho populacional foi estimado em 34 (10 111) indivíduos e a densidade em 2,36 (1,58 7,79) indivíduos/km². Entretanto, a proporção de área utilizada foi estimada em 21%, indicando que a densidade para as áreas realmente ocupadas pode ser mais alta. A intensidade de uso da área parece estar correlacionada principalmente à densidade do sub-bosque e à oferta de suplementação alimentar. A taxa de crescimento populacional foi estimada em -0,047 (-0,137 0,018), o que indica um declínio. É possível que este declínio esteja ligado ao tamanho reduzido da população, que a torna mais susceptível à estocasticidade demográfica, ambiental e genética e ao efeito Allee. Os mesmos fatores também podem estar provocando um desvio na razão sexual, estimada em 0,35 (0,20 0,47). / Fragmentation and habitat loss are the two main causes of population and biodiversity decline, followed by overhunting. Such impacts made the Cracidae family the most endangered bird family in American continents. In Brazil, many reintroduction programs focused on cracids. The first one reintroduced the Red-billed Curassow (Crax blumenbachii Spix, 1825) in Ipaba, MG, Brazil. This work aimed to estimate the population size and density, the sex ratio and the landscape use of the Red-billed Curassow population reintroduced in Ipaba. We collected the data along 6 months through line-transects, totalizing 280 km of effort. The analysis followed distance sampling and occupancy protocols. We estimated the population size in 34 (10 111) birds and the density was 2.36 (1.58 7.79) birds/ha. However, we estimated the proportion of area effective used in 21%, what means that the density for such area might be higher. Apparently, the intensity of habitat use is mostly correlated to the understory density and to food supplementation. We estimated the population growth rate in -0.047 (-0.137 0.018), what indicates a decrease. Its possible that the population is declining due to its size, once small populations are more likely to suffer because of demographic, environmental and genetic stochasticity and Allee effect. The same factors might explain the skewed sex ratio, estimated in 0.35 (0.20 0.47).

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