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USGS2016

Can captive populations function as sources of genetic variation for reintroductions into the wild? A case study of the Arabian oryx from the Phoenix Zoo and the Shaumari Wildlife Reserve, Jordan

The Arabian oryx ( Oryx leucoryx ) historically ranged across the Arabian Peninsula and neighboring countries until its extirpation in 1972. In 1963–1964 a captive breeding program for this species was started at the Phoenix Zoo (PHX); it ultimately consisted of 11 animals that became known as the ‘World Herd’. In 1978 – 1979 a wild population was established at the Shaumari Wildlife Reserve (SWR), Jordan, with eight descendants from the World Herd and three individuals from Qatar. We described the mtDNA and nuclear genetic diversity and structure of PHX and SWR. We also determined the long-term demographic and genetic viability of these populations under different reciprocal translocation scenarios. PHX displayed a greater number of mtDNA haplotypes ( n = 4) than SWR ( n = 2). Additionally, PHX and SWR presented nuclear genetic diversities of N ¯ A N¯A = 2.88 vs. 2.75, H ¯ O H¯O = 0.469 vs. 0.387, and H ¯ E H¯E = 0.501 vs. 0.421, respectively. Although these populations showed no signs of inbreeding ( F ¯ IS F¯IS ≈ 0), they were highly differentiated ( G ′ ′ ST GST′′ = 0.580; P < 0.001). Migration between PHX and SWR ( Nm = 1, 4, and 8 individuals/generation) increased their genetic diversity in the short-term and substantially reduced the probability of extinction in PHX during 25 generations. Under such scenarios, maximum genetic diversities were achieved in the first generations before the effects of genetic drift became predominant. Although captive populations can function as sources of genetic variation for reintroduction programs, we recommend promoting mutual and continuous gene flow with wild populations to ensure the long-term survival of this species.

Conservation Genetics↗

USGS2013

Oryx callotis (Artiodactyla: Bovidae)

Oryx callotis O. Thomas, 1982 (fringe-eared oryx) is a relatively large, long-bodied bovid, with an appropriate common name because of its distinguishing tufts of hair extending from the ends of the ears. It occupies arid lands in Kenya and Tanzania. O. callotis can go up to a month without drinking water if succulent vegetation is available. Some herds have been semidomesticated, and 60% of the presumed 17,000 wild individuals exist in wildlife reserves, currently receiving some protection from settlement and poaching. O. callotis is considered “Vulnerable” by the International Union for Conservation of Nature and Natural Resources but as a subspecies of O. beisa , which is listed as “Near Threatened.”

Mammalian Species↗

USGS2003

Evidence of three new members of malignant catarrhal fever virus group in Muskox (Ovibos moschatus), Nubian ibex (Capra nubiana), and gemsbok (Oryx gazella)

Six members of the malignant catarrhal fever (MCF) virus group of ruminant rhadinoviruses have been identified to date. Four of these viruses are clearly associated with clinical disease: alcelaphine herpesvirus 1 (AlHV-1) carried by wildebeest (Connochaetes spp.); ovine herpesvirus 2 (OvHV-2), ubiquitous in domestic sheep; caprine herpesvirus 2 (CpHV-2), endemic in domestic goats; and the virus of unknown origin found causing classic MCF in white-tailed deer (Odocoileus virginianus; MCFV-WTD). Using serology and polymerase chain reaction with degenerate primers targeting a portion of the herpesviral DNA polymerase gene, evidence of three previously unrecognized rhadinoviruses in the MCF virus group was found in muskox (Ovibos moschatus), Nubian ibex (Capra nubiana), and gemsbok (South African oryx, Oryx gazella), respectively. Based on sequence alignment, the viral sequence in the muskox is most closely related to MCFV-WTD (81.5% sequence identity) and that in the Nubian ibex is closest to CpHV-2 (89.3% identity). The viral sequence in the gemsbok is most closely related to AlHV-1 (85.1% identity). No evidence of disease association with these viruses has been found. ?? Wildlife Disease Association 2003.

Journal of Wildlife Diseases↗

USGS2017

Estimating inbreeding rates in natural populations: Addressing the problem of incomplete pedigrees

Understanding and estimating inbreeding is essential for managing threatened and endangered wildlife populations. However, determination of inbreeding rates in natural populations is confounded by incomplete parentage information. We present an approach for quantifying inbreeding rates for populations with incomplete parentage information. The approach exploits knowledge of pedigree configurations that lead to inbreeding coefficients of F = 0.25 and F = 0.125, allowing for quantification of Pr( I | k ): the probability of observing pedigree I given the fraction of known parents ( k ). We developed analytical expressions under simplifying assumptions that define properties and behavior of inbreeding rate estimators for varying values of k . We demonstrated that inbreeding is overestimated if Pr( I | k ) is not taken into consideration and that bias is primarily influenced by k . By contrast, our new estimator, incorporating Pr( I | k ), is unbiased over a wide range of values of k that may be observed in empirical studies. Stochastic computer simulations that allowed complex inter- and intragenerational inbreeding produced similar results. We illustrate the effects that accounting for Pr( I | k ) can have in empirical data by revisiting published analyses of Arabian oryx ( Oryx leucoryx ) and Red deer ( Cervus elaphus ). Our results demonstrate that incomplete pedigrees are not barriers for quantifying inbreeding in wild populations. Application of our approach will permit a better understanding of the role that inbreeding plays in the dynamics of populations of threatened and endangered species and may help refine our understanding of inbreeding avoidance mechanisms in the wild.

Journal of Heredity↗

USGS2017

Diet composition, quality and overlap of sympatric American pronghorn and gemsbok

Species with a long evolutionary history of sympatry often have mechanisms for resource partitioning that reduce competition. However, introduced non-native ungulates often compete with native ungulates and competitive effects can be exacerbated in arid regions due to low primary productivity. Our objectives were to characterize diet composition, quality, and overlap between American pronghorn Antilocapra americana and introduced non-native gemsbok Oryx gazella in southcentral New Mexico, USA. Severe drought occurred between 2010 and 2011, which allowed us to evaluate drought impacts on diet composition, quality, and overlap. Using feces collected from each species, we assessed diet composition and overlap with microhistological analysis and diet quality using fecal nitrogen (FN) and fecal 2,6-diaminopimelic acid (FDAPA). Pronghorn diet was primarily composed of shrubs in the cool—dry season (64.5%) then shifted to forbs in the warm—dry (64.7%) and warm—wet (54.1%) seasons. Pronghorn diet also shifted to shrubs during drought (50.7%). Gemsbok diets were evenly distributed across forage types. Fifty-three percent of the species of plants consumed by pronghorn and gemsbok were shared; diet overlap averaged 0.44 ± 0.06 (SE) and 0.49 ± 0.06 during the warm—dry seasons of 2010 and 2011, respectively. During drought, key forage species shared between pronghorn and gemsbok included yucca Yucca spp., prickly pear Opuntia spp., globemallow Sphaeralcea coccinea and horsenettle Solanum elaeagnifolium, comprising 50% of the pronghorn and 40% of the gemsbok diets. Fecal nitrogen and FDAPA decreased in pronghorn by 26% and 27% between the warm—dry season of 2010 (non-drought) and the warm—dry season of 2011 (drought), respectively. Drought had little effect on dietary quality for gemsbok. Gemsbok can use forage with lower nutritional content giving them an advantage over pronghorn, particularly during drought periods. Pronghorn are more dependent upon precipitation, which may be important to consider in light of increasing drought frequency associated with climate change.

New Mexico↗

USGS2003

Infectious disease survey of gemsbok in New Mexico

Exotic wildlife can introduce new diseases or act as reservoirs of endemic diseases. On White Sands Missile Range, New Mexico (USA), significant declines in populations of native ungulates generally correspond to increases in range and population density of the exotic gemsbok (Oryx gazella gazella), introduced beginning in 1969. We surveyed gemsbok in 2001 for exposure to a variety of diseases potentially important for native ungulates. High seroprevalence was found for malignant catarrhal fever virus (49 [98%] of 50 sera; 43 [96%] of 45 plasma samples), bluetongue virus (48 [96%] of 50), bovine respiratory syncytial virus (33 [66%] of 50), and parainfluenza-3 virus (10 [20%] of 50). Low numbers of Nematodirus spp. eggs in a few individuals were the only parasites detected in gemsbok . Exposure to the above diseases in gemsbok is of interest to managers because of potential implications for recovery of desert bighorn sheep (Ovis canadensis mexicana) and desert mule deer (Odocoileus hemionus crooki) in the White Sands area because each has been implicated in mortality in these species either in the White Sands area or elsewhere in the western/southwestern United States.

New Mexico↗

USGS2009

The reintroduction of the Andean condor into Colombia, South America: 1989-1991

From 1989 to 1991,22 captive-reared Andean condors Vultur gryphus were released into three protected areas in the Andes of Colombia, South America. The goals of this reintroduction programme were to re-establish populations of these birds in protected habitat where the species had been extirpated, and to train local biologists in the conservation techniques necessary to recover their native condor. All birds were hatched, reared and released according to the protocols established by the US Fish and Wildlife Service and the California Department of Fish and Game for the California condor Gymnogyps californianus. At the time of release, the birds ranged in age from 11 to 26 months. Each bird was fitted with individually numbered wing tags and wing-mounted radio transmitters. Of the 22 released animals, 19 currently survive – a substantial increase to the wild population in Colombia, which had been estimated by Colombian biologists to number only 20 individuals.

Oryx↗

USGS2009

The manatee in Haiti

The future looks bleak for the manatee population in the waters around Haiti. Results of a survey conducted by the US Fish and Wildlife Service suggest that numbers have declined drastically over the last 50 years. The best hope for the few remaining is that the hunting expertise will vanish with the older generation.

Oryx↗

USGS2009

Belize--a last stronghold for manatees in the Caribbean

Belize is a small country but it offers a safe haven for the largest number of manatees in the Caribbean. The authors' survey in 1989 revealed that there has been no apparent decline since the last study in 1977. However, there is no evidence for population growth either and as the Belize economy develops threats from fisheries, human pressure and declining habitat quality will increase. Recommendations are made to ensure that Belize safeguards its manatee populations.

Oryx↗

USGS2003

Population increase in Kirtland's warbler and summer range expansion to Wisconsin and Michigan's Upper Peninsula, USA

The threatened Kirtland's warbler Dendroica kirtlandii breeds in stands of young jack pine Pinus banksiana growing on well-drained soils in Michigan, USA. We summarize information documenting the range expansion of Kirtland's warbler due to increased habitat management in the core breeding range in the Lower Peninsula of Michigan during 1990–2000. We collected records and conducted searches for the species in Michigan's Upper Peninsula and Wisconsin over 1978–2000. During that time 25 males were found in Wisconsin and 90 males in the Upper Peninsula. We documented colonization of Michigan's Upper Peninsula by six ringed males from the Lower Peninsula of Michigan. Four ringed birds also moved back to the core breeding range, including two males that made two-way movements between the core breeding range and the Upper Peninsula. Thirty-seven females were observed with males from 1995 to 2000, all in Michigan. Nesting activities were noted for 25 pairs and at least nine nests fledged young. One male ringed as a fledgling returned to breed in two subsequent years. After a 19-year period of population stability, the Kirtland's warbler population increased four-fold during 1990–2000, most likely in response to a tripling in habitat area. This increase in sightings and documented breeding may be related to habitat availability in Michigan's Upper Peninsula and to saturation of habitat in the main breeding range. The increase in extra-limital records during 1995–1999 corresponds to the time when the population went from the minimum to the maximum projected population densities, and a decline in natural wildfire habitat was just offset by new managed habitat for the Kirtland's warbler.

Michigan, Wisconsin↗

USGS2003

Monitoring of biological diversity — A response to Danielsen et al

No abstract available.

Oryx↗

USGS2007

Remote camera-trap methods and analyses reveal impacts of rangeland management on Namibian carnivore communities

Assessing the abundance and distribution of mammalian carnivores is vital for understanding their ecology and providing for their long-term conservation. Because of the difficulty of trapping and handling carnivores many studies have relied on abundance indices that may not accurately reflect real abundance and distribution patterns. We developed statistical analyses that detect spatial correlation in visitation data from combined scent station and camera-trap surveys, and we illustrate how to use such data to make inferences about changes in carnivore assemblages. As a case study we compared the carnivore communities of adjacent communal and freehold rangelands in central Namibia. We used an index of overdispersion to test for repeat visits to individual camera-trap scent stations and a bootstrap simulation to test for correlations in visits to camera neighbourhoods. After distilling our presence-absence data to the most defensible spatial scale, we assessed overall carnivore visitation using logistic regression. Our analyses confirmed the expected pattern of a depauparate fauna on the communal rangelands compared to the freehold rangelands. Additionally, the species that were not detected on communal sites were the larger-bodied carnivores. By modelling these rare visits as a Poisson process we illustrate a method of inferring whether or not such patterns are because of local extinction of species or are simply a result of low sample effort. Our Namibian case study indicates that these field methods and analyses can detect meaningful differences in the carnivore communities brought about by anthropogenic influences. ?? 2007 FFI.

Oryx↗

USGS2007

How many tigers Panthera tigris are there in Huai Kha Khaeng Wildlife Sanctuary, Thailand? An estimate using photographic capture-recapture sampling

We used capture-recapture analyses to estimate the density of a tiger Panthera tigris population in the tropical forests of Huai Kha Khaeng Wildlife Sanctuary, Thailand, from photographic capture histories of 15 distinct individuals. The closure test results (z = 0.39, P = 0.65) provided some evidence in support of the demographic closure assumption. Fit of eight plausible closed models to the data indicated more support for model Mh, which incorporates individual heterogeneity in capture probabilities. This model generated an average capture probability = 0.42 and an abundance estimate of = 19 (9.65) tigers. The sampled area of = 477.2 (58.24) km 2 yielded a density estimate of = 3.98 (0.51) tigers per 100 km 2 . Huai Kha Khaeng Wildlife Sanctuary could therefore hold 113 tigers and the entire Western Forest Complex c. 720 tigers. Although based on field protocols that constrained us to use sub-optimal analyses, this estimated tiger density is comparable to tiger densities in Indian reserves that support moderate prey abundances. However, tiger densities in well-protected Indian reserves with high prey abundances are three times higher. If given adequate protection we believe that the Western Forest Complex of Thailand could potentially harbour >2,000 wild tigers, highlighting its importance for global tiger conservation. The monitoring approaches we recommend here would be useful for managing this tiger population.

Huai Kha Khaeng Wildlife Sanctuary↗

USGS2012

Cryptic extinction of a common Pacific lizard Emoia impar (Squamata, Scincidae) from the Hawaiian Islands.

Most documented declines of tropical reptiles are of dramatic or enigmatic species. Declines of widespread species tend to be cryptic. The early (1900s) decline and extinction of the common Pacific skink Emoia impar from the Hawaiian Islands is documented here through an assessment of literature, museum vouchers and recent fieldwork. This decline appears contemporaneous with the documented declines of invertebrates and birds across the Hawaiian Islands. A review of the plausible causal factors indicates that the spread of the introduced big-headed ant Pheidole megacephala is the most likely factor in this lizard decline. The introduction and spread of a similar skink Lampropholis delicata across the islands appears to temporally follow the decline of E. impar , although there is no evidence of competition between these species. It appears that L. delicata is spreading to occupy the niche vacated by the extirpated E. impar . Further confusion exists because the skink E. cyanura , which is very similar in appearance to E. impar , appears to have been introduced to one site within a hotel on Kaua'i and persisted as a population at that site for approximately 2 decades (1970s–1990s) but is now also extirpated. This study highlights the cryptic nature of this early species extinction as evidence that current biogeographical patterns of non-charismatic or enigmatic reptiles across the Pacific may be the historical result of early widespread invasion by ants. Conservation and restoration activities for reptiles in the tropical Pacific should consider this possibility and evaluate all evidence prior to any implementation.

Hawai'i↗

USGS2013

The precarious persistence of the endangered Sierra Madre yellow-legged frog Rana muscosa in southern California, USA

We conducted surveys for the Endangered Sierra Madre yellow-legged frog Rana muscosa throughout southern California to evaluate the current distribution and status of the species. Surveys were conducted during 2000–2009 at 150 unique streams and lakes within the San Gabriel, San Bernardino, San Jacinto, and Palomar mountains of southern California. Only nine small, geographically isolated populations were detected across the four mountain ranges, and all tested positive for the amphibian chytrid fungus Batrachochytrium dendrobatidis . Our data show that when R. muscosa is known to be present it is easily detectable (89%) in a single visit during the frog's active season. We estimate that only 166 adult frogs remained in the wild in 2009. Our research indicates that R. muscosa populations in southern California are threatened by natural and stochastic events and may become extirpated in the near future unless there is some intervention to save them.

California↗

USGS2014

Breeding loggerhead marine turtles Caretta caretta in Dry Tortugas National Park, USA, show high fidelity to diverse habitats near nesting beaches

We used satellite telemetry to identify in-water habitat used by individuals in the smallest North-west Atlantic subpopulation of adult nesting loggerhead turtles Caretta caretta during the breeding season. During 2010, 2011 and 2012 breeding periods, a total of 20 adult females used habitats proximal to nesting beaches with various levels of protection within Dry Tortugas National Park. We then used a rapid, high-resolution, digital imaging system to map habitat adjacent to nesting beaches, revealing the diversity and distribution of available benthic cover. Turtle behaviour showing measurable site-fidelity to these diverse habitats has implications for managing protected areas and human activities within them. Protecting diverse benthic areas adjacent to loggerhead turtle nesting beaches here and elsewhere could provide benefits for overall biodiversity conservation.

Florida↗

USGS2015

Status assessment of the Endangered snow leopard Panthera uncia and other large mammals in the Kyrgyz Alay , using community knowledge corrected for imperfect detection

The Endangered snow leopard Panthera uncia occurs in the Central Asian Mountains, which cover c. 2 million km 2 . Little is known about its status in the Kyrgyz Alay Mountains, a relatively narrow stretch of habitat connecting the southern and northern global ranges of the species. In 2010 we gathered information on current and past (1990, the last year of the Soviet Union) distributions of snow leopards and five sympatric large mammals across 14,000 km 2 of the Kyrgyz Alay. We interviewed 95 key informants from local communities. Across 49 400-km 2 grid cells we obtained 1,606 and 962 records of species occurrence (site use) in 1990 and 2010, respectively. The data were analysed using the multi-season site occupancy framework to incorporate uncertainty in detection across interviewees and time periods. High probability of use by snow leopards in the past was recorded in > 70% of the Kyrgyz Alay. Between the two sampling periods 39% of sites showed a high probability of local extinction of snow leopard. We also recorded high probability of local extinction of brown bear Ursus arctos (84% of sites) and Marco Polo sheep Ovis ammon polii (47% of sites), mainly in regions used intensively by people. Data indicated a high probability of local colonization by lynx Lynx lynx in 41% of the sites. Although wildlife has declined in areas of central and eastern Alay, regions in the north-west, and the northern and southern fringes appear to retain high conservation value.

Oryx↗

USGS2015

An alternative framework for responding to the amphibian crisis

Volumes of data illustrate the severity of the crisis affecting amphibians, where > 32% of amphibians worldwide are threatened with declining populations. Although there have been isolated victories, the current approach to the issue is unsuccessful. We suggest that a radically different approach, something akin to human emergency response management (i.e. the Incident Command System), is one alternative to addressing the inertia and lack of cohesion in responding to amphibian issues. We acknowledge existing efforts and the useful research that has been conducted, but we suggest that a change is warranted and that the identification of a new amphibian chytrid provides the impetus for such a change. Our goal is to recognize that without a centralized effort we (collectively) are likely to fail in responding to this challenge.

Oryx↗