Filters: Tags: conservation genetics (X)272 results (12ms)
Optimized DNA extraction methods for encysted embryos of the endangered fairy shrimp, Branchinecta sandiegonensis
The San Diego fairy shrimp Branchinecta sandiegonensis is a federally endangered species endemic to vernal pools in southern California, USA. Filling events in these habitats are highly variable, with some pools failing to hold water long enough for reproduction over many successive years. Studies of this species are thus hindered by the relatively rare appearance of aquatically active life history phases. Because diapausing cysts are abundant and present at all times, they provide an underutilized opportunity for both species identification and genetic studies. However, methods for extracting DNA from cysts are technically challenging because of their structure and size. Here we present a protocol for extracting...
Rangewide phylogeography and landscape genetics of the Western U.S. endemic frog Rana boylii (Ranidae): Implications for the conservation of frogs and rivers
Genetic data are increasingly being used in conservation planning for declining species. We sampled both the ecological and distributional limits of the foothill yellow-legged frog, Rana boylii to characterize mitochondrial DNA (mtDNA) variation in this declining, riverine amphibian. We evaluated 1525 base pairs (bp) of cytochrome b and ND2 fragments for 77 individuals from 34 localities using phylogenetic and population genetic analyses. We constructed gene trees using maximum likelihood and Bayesian inference, and quantified genetic variance (using AMOVA and partial Mantel tests) within and among hydrologic regions and river basins. Several moderately supported, geographically-cohesive mtDNA clades were recovered...
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...
Microsatellite DNA variation Atlantic sturgeon (Acipenser oxyrinchus oxyrinchus) and cross-species amplification the Acipenseridae
A century of landscape disturbance and urbanization of the San Francisco Bay region affects the present-day genetic diversity of the California Ridgway’s rail (<i>Rallus obsoletus obsoletus</i>)
Fragmentation and loss of natural habitat have important consequences for wild populations and can negatively affect long-term viability and resilience to environmental change. Salt marsh obligate species, such as those that occupy the San Francisco Bay Estuary in western North America, occupy already impaired habitats as result of human development and modifications and are highly susceptible to increased habitat loss and fragmentation due to global climate change. We examined the genetic variation of the California Ridgway’s rail (Rallus obsoletus obsoletus), a state and federally endangered species that occurs within the fragmented salt marsh of the San Francisco Bay Estuary. We genotyped 107 rails across 11...
Landscape genomics of Sphaeralcea ambigua in the Mojave Desert: a multivariate, spatially-explicit approach to guide ecological restoration
Local adaptation influences plant species’ responses to climate change and their performance in ecological restoration. Fine-scale physiological or phenological adaptations that direct demographic processes may drive intraspecific variability when baseline environmental conditions change. Landscape genomics characterize adaptive differentiation by identifying environmental drivers of adaptive genetic variability and mapping the associated landscape patterns. We applied such an approach to Sphaeralcea ambigua, an important restoration plant in the arid southwestern United States, by analyzing variation at 153 amplified fragment length polymorphism loci in the context of environmental gradients separating 47 Mojave...
Phylogeography and population genetic structure of double-crested cormorants (Phalacrocorax auritus)
We examined the genetic structure of doublecrested cormorants (Phalacrocorax auritus) across their range in the United States and Canada. Sequences of the mitochondrial control region were analyzed for 248 cormorants from 23 breeding sites. Variation was also examined at eight microsatellite loci for 409 cormorants from the same sites. The mitochondrial and microsatellite data provided strong evidence that the Alaskan subspecies (P. a. cincinnatus) is genetically divergent from other populations in North America (net sequence divergence = 5.85 %;UST for mitochondrial control region = 0.708; FST for microsatellite loci = 0.052). Historical records, contemporary population estimates, and field observations are consistent...
Extensive clonality in the endangered shrub Haloragodendron lucasii (Haloragaceae) revealed by allozymes and RAPDs
Assessment of genetic diversity in a Morus germplasm collection using fluorescence-based AFLP markers
Hydrography and population genetic structure in brook charr (Salvelinus fontinalis, Mitchill) from eastern Canada
Genetic analysis and conservation of 31 surviving individuals of a rare New Zealand tree, Metrosideros bartlettii (Myrtaceae)
Brief communication. Karyotype identity of two subspecies of Eld's deer [Cervus eldi (Cervinae, Artiodactyla)] and its consequences for conservation
Provenance of a New Zealand brush-tailed rock-wallaby (Petrogale penicillata ) population determined by mitochondrial DNA sequence analysis