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Nichols R.K.,Wildlife Preservation Canada | Steiner J.,Wildlife Preservation Canada | Woolaver L.G.,Wildlife Preservation Canada | Williams E.,Wildlife Preservation Canada | And 2 more authors.
ORYX | Year: 2010

The term field propagation and release refers to the breeding of captive adults in large field enclosures, allowing them to raise their young, and then releasing those young from that location. This technique is currently being implemented in Canada as one of several recovery tools for the endangered eastern loggerhead shrike Lanius ludovicianus migrans. During 2001-2007 a total of 360 shrike fledglings were produced in field propagation enclosures and 301 were released from these enclosures. Annual return rates of birds released since 2004 are 2-6.6%. Seventeen released birds have been re-sighted, including 10 birds that have returned to the breeding grounds the following season to produce young with wild mates. The high annual return rate of release birds and the successful integration of these birds into the wild breeding population represent important milestones for the recovery of this population. The management technique we describe here has the potential to be applicable to other species that require natural habitat for breeding and/or are reliant on a suite of parent-learned behaviours that cannot be accommodated for or adequately replicated within intensive close captive-breeding or hand-rearing conditions. Copyright © 2010 Fauna & Flora International.


Kerr J.T.,University of Ottawa | Pindar A.,University of Ottawa | Galpern P.,University of Calgary | Packer L.,York University | And 10 more authors.
Science | Year: 2015

For many species, geographical ranges are expanding toward the poles in response to climate change, while remaining stable along range edges nearest the equator. Using long-term observations across Europe and North America over 110 years, we tested for climate change-related range shifts in bumblebee species across the full extents of their latitudinal and thermal limits and movements along elevation gradients. We found cross-continentally consistent trends in failures to track warming through time at species' northern range limits, range losses from southern range limits, and shifts to higher elevations among southern species. These effects are independent of changing land uses or pesticide applications and underscore the need to test for climate impacts at both leading and trailing latitudinal and thermal limits for species. © 2015, American Association for the Advancement of Science. All rights reserved.


Woolaver L.G.,York University | Nichols R.K.,Wildlife Preservation Canada | Morton E.S.,York University | Stutchbury B.J.M.,York University
Journal of Tropical Ecology | Year: 2015

Patterns of social organization and mating systems have been shown to be functions of ecological factors such as resource allocation and breeding density. In some species, particularly birds, social organization and genetic mating systems differwithmolecular studies providing evidence of extra-pair young frequently occurring within broods of socially monogamous species. Herewe examine the social and genetic mating system of an ecologically little-known forest raptor endemic to the island of Hispaniola in the Caribbean. From 2005-2009, our field observations of over 60 breeding pairs verified a social mating system of monogamy for the species. During the same time period, we collected blood samples (n = 146 birds, 48 nests) and used microsatellite profiles from 10 loci to estimate genetic relatedness among nestlings in a brood and assign putative fathers. We found no evidence of extra-pair paternity in 41 broods.We had one instance where a socialmale was not assigned as the putative father, however, the confidence level of this assignment was not significant since the genotypes of the social and assigned males were very similar. Our results support our hypothesis that genetic monogamy would be exhibited by Ridgway's hawk, an island-endemic tropical raptor. © Cambridge University Press 2013.


Woolaver L.G.,York University | Woolaver L.G.,British Petroleum | Nichols R.K.,Wildlife Preservation Canada | Morton E.S.,York University | Stutchbury B.J.M.,York University
Bird Conservation International | Year: 2015

Ridgway's Hawk Buteo ridgwayi is a Critically Endangered forest raptor endemic to the island of Hispaniola in the Caribbean. The species is currently limited to a small area on the north-east coast of the island, with fewer than 110 pairs remaining. From 2005 to 2009 we studied its breeding ecology, finding that Ridgway's Hawks have a clutch size (2.0 ± 0.4 eggs) similar to other tropical raptors and island Buteo species. Fledging rate of 0.64 fledglings per active nest (fledgling nest-1) with pairs raising a single brood per year was also similar to that of other tropical Buteo species. Nest success was 40% (n = 151), with the majority of nest failures caused by human disturbance. The two significant predictors of nest success and fledging rate were related to human persecution: nest height and territory disturbance index. Pairs were able to tolerate human activity in their territory if there was no direct disturbance to the immediate nest area. Conservation planning for Ridgway's Hawk must focus on community awareness programmes targeting local user groups within Los Haitises National Park regarding the uniqueness and endangered status of the hawk, and effective protection of the remaining karst forest in Los Haitises. © 2014 BirdLife International.


Imlay T.I.,Wildlife Preservation Canada | Crowley J.F.,University of Guelph | Crowley J.F.,Mcfarlane | Argue A.M.,University of Guelph | And 4 more authors.
Biological Conservation | Year: 2010

Avian captive breeding programs pose a particular challenge with migratory birds due to natal dispersal and high mortality during migration. In Canada a captive breeding program for the eastern loggerhead shrike (Lanius ludovicianus migrans) has released over 400 juveniles since 2001, but the fate of almost all these birds is unknown. In 2007 and 2008, we used radio-telemetry of captive-reared juveniles to determine pre-migration survival and dispersal movements away from the release site. Overall, 76% (29 of 38) of shrikes survived from release to the initiation of migration and the daily survival rate was 0.987. Most deaths (78%) occurred in females, suggesting a possible sex-biased pre-migration mortality. Shrikes typically dispersed independently, there was little overlap between dispersal sites, and the average pre-migration dispersal distance from the release site was 4.2. km (SD 2.4). Release date was negatively correlated with time spent at the release site prior to dispersal, but did not have a significant effect on survival, time spent at dispersal sites or distance of dispersal. Migration initiation date ranged over 6. weeks and early-hatched juveniles were the first to begin migration. Using aerial telemetry, we located five of 29 birds that had begun migration at distances up to 180. km from the release site; no birds were found dead after initiating migration despite the extensive search area. High juvenile survival to migration for captive-reared juveniles suggests that the captive breeding and release program has high potential to augment wild populations of the eastern loggerhead shrike. © 2010 Elsevier Ltd.


Davy C.M.,University of Toronto | Davy C.M.,Royal Ontario Museum | Leifso A.E.,Wildlife Preservation Canada | Conflitti I.M.,University of Toronto | And 3 more authors.
Conservation Genetics Resources | Year: 2012

We use 454 ("shotgun") sequencing to obtain a partial genomic library for the snapping turtle (Chelydra serpentina). We characterize ten microsatellite loci from these sequences and test cross-amplification of loci originally developed for the alligator snapping turtle (Macrochelys temminckii). We genotype 127 individuals from Ontario at twelve loci. The number of alleles per locus ranges from 1 to 14; heterozygosity ranges from 0.157 to 0.850. These loci will be used to study population genetic structure in this long-lived reptile and may cross-amplify in two closely related species. © 2012 Springer Science+Business Media B.V.


Davy C.M.,Wildlife Preservation Canada | Davy C.M.,Trent University | Kidd A.G.,Ontario Ministry of Natural Resources | Wilson C.C.,Ontario Ministry of Natural Resources
PLoS ONE | Year: 2015

Environmental DNA (eDNA) is a potentially powerful tool for detection and monitoring of rare species, including threatened native species and recently arrived invasive species. Here, we develop DNA primers for a suite of nine sympatric freshwater turtles, and use it to test whether turtle eDNA can be successfully detected in samples from aquaria and an outdoor pond. We also conduct a cost comparison between eDNA detection and detection through traditional survey methods, using data from field surveys at two sites in our target area. We find that eDNA from turtles can be detected using both conventional polymerase chain reaction (PCR) and quantitative PCR (qPCR), and that the cost of detection through traditional survey methods is 2-10X higher than eDNA detection for the species in our study range. We summarize necessary future steps for application of eDNA surveys to turtle monitoring and conservation and propose specific cases in which the application of eDNA could further the conservation of threatened turtle species. Copyright: © 2015 Davy et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.


Davy C.M.,Wildlife Preservation Canada | Davy C.M.,University of Toronto | Paterson J.E.,University of Ottawa | Leifso A.E.,Wildlife Preservation Canada
Animal Behaviour | Year: 2014

Fitness proxies such as performance measures are used to quantify relative fitness in systems where direct measurements are unobtainable. To provide meaningful results at the individual level, fitness proxies must demonstrate not only repeatability, as measured by high intraclass correlation coefficients, but also rank repeatability. Here we illustrate the importance of rank repeatability in fitness proxies using a commonly employed example: righting time in hatchling turtles. Our results show that individual righting time varies strongly among trials and is not replicable enough to provide repeatable rankings of individuals or clutches. To illustrate the potential implications of this finding, we use our data to test the predication that larger turtles have faster righting times, using three consecutive trials of righting time. The resulting conclusions vary substantially among trials. Thus, we conclude that righting time does not meet the criterion of rank repeatability required for estimates of relative individual fitness, performance or phenotypic quality. Researchers employing similar proxies should assess the rank repeatability of a proxy before applying it to questions of relative individual fitness. If a measure shows satisfactory repeatability, the final test for a fitness proxy is to demonstrate a correlation with actual fitness, ideally in the organism's natural habitat. © 2014 The Association for the Study of Animal Behaviour.


Brace S.,Royal Holloway, University of London | Barnes I.,Royal Holloway, University of London | Powell A.,University College London | Pearson R.,Imperial College London | And 4 more authors.
Molecular Ecology | Year: 2012

Hispaniola is a geotectonically complex island consisting of two palaeo-islands that docked c. 10 Ma, with a further geological boundary subdividing the southern palaeo-island into eastern and western regions. All three regions have been isolated by marine barriers during the late Cenozoic and possess biogeographically distinct terrestrial biotas. However, there is currently little evidence to indicate whether Hispaniolan mammals show distributional patterns reflecting this geotectonic history, as the island's endemic land mammal fauna is now almost entirely extinct. We obtained samples of Hispaniolan hutia (Plagiodontia aedium), one of the two surviving Hispaniolan land mammal species, through fieldwork and historical museum collections from seven localities distributed across all three of the island's biogeographic regions. Phylogenetic analysis using mitochondrial DNA (cytochrome b) reveals a pattern of historical allopatric lineage divergence in this species, with the spatial distribution of three distinct hutia lineages biogeographically consistent with the island's geotectonic history. Coalescent modelling, approximate Bayesian computation and approximate Bayes factor analyses support our phylogenetic inferences, indicating near-complete genetic isolation of these biogeographically separate populations and differing estimates of their effective population sizes. Spatial congruence of hutia lineage divergence is not however matched by temporal congruence with divergences in other Hispaniolan taxa or major events in Hispaniola's geotectonic history; divergence between northern and southern hutia lineages dates to c. 0.6 Ma, significantly later than the unification of the palaeo-islands. The three allopatric Plagiodontia populations should all be treated as distinct management units for conservation, with particular attention required for the northern population (low haplotype diversity) and the south-western population (high haplotype diversity but highly threatened). © 2012 Blackwell Publishing Ltd.


Lagios E.L.,Wildlife Preservation Canada | Robbins K.F.,Wildlife Preservation Canada | Lapierre J.M.,Wildlife Preservation Canada | Steiner J.C.,Wildlife Preservation Canada | Imlay T.L.,Wildlife Preservation Canada
ORYX | Year: 2015

High post-release survival, low dispersal and the recruitment of captive-reared individuals into the wild population are critical to the success of any reintroduction programme. Reintroducing a migratory species poses an additional challenge as success also depends on the return of captive-reared individuals to breeding grounds in subsequent years. We investigated the effects of seven husbandry and management factors on the return rate of captive-reared eastern loggerhead shrikes Lanius ludovicianus migrans and documented the recruitment of returning individuals. During 2004-2010, 564 juveniles were released in Ontario, Canada, as part of a field propagation and release programme and there were 27 confirmed sightings of returning birds during 2005-2011. Returning birds were significantly more likely to have been released in large groups of juveniles (9-10 birds) at 5.5 weeks post-fledging from the Carden field propagation site. Comparisons of the number of young fledged and survival to 2 weeks post-fledging revealed similar results for pairs comprising one captive-reared and one wild-reared individual and pairs comprising two wild individuals. These results highlight the contribution of captive-reared shrikes to the recovery of the wild population and the importance of monitoring outcomes and evaluating techniques. Copyright © Fauna & Flora International 2014.

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