Eastern Subpopulation Research Articles

Food availability aligns with contrasting demographics in populations of an at-risk songbird.

Golden-winged Warblers (Vermivora chrysoptera) have become rare across much of their historic breeding range and response to conservation efforts is variable. Evidence from several recent studies suggests that breeding output is a primary driver explaining responses to conservation and it is hypothesized that differences in food availability may be driving breeding output disparity between two subpopulations of the warbler's Appalachian breeding range. Herein, we studied two subpopulations: central Pennsylvania ("central subpopulation"), where breeding productivity is relatively low, and eastern Pennsylvania ("eastern subpopulation"), where breeding productivity is relatively high. To test the food-availability hypothesis in this system, we measured density of caterpillars, plasma lipid metabolites (triglycerides [TRIG; fat deposition] and glycerol [GLYC; fat breakdown]), body mass of adults males, and acquired body mass data for fledglings at 38 sites managed for nesting habitat. Consistent with our prediction, leaf-roller caterpillar density, the group upon which Golden-winged Warblers specialize, was 45× lower in the central subpopulation than the eastern subpopulation. TRIG concentrations were highest within the eastern subpopulation during breeding grounds arrival. The change in TRIG concentrations from the breeding-grounds-arrival stage to the nestling-rearing stage was subpopulation dependent: TRIG decreased in the eastern subpopulation and was constant in the central subpopulation, resulting in similar concentrations during the nestling-rearing stage. Furthermore, GLYC concentrations were higher in the eastern subpopulation, which suggests greater energy demands in this region. Despite this, adult male warblers in the eastern subpopulation maintained a higher average body mass. Finally, fledgling body mass was 16% greater in the eastern subpopulation than the central subpopulation before and after fledging. Collectively, our results suggest that poor breeding success of Golden-winged Warblers in the central subpopulation could be driven by lower availability of primary prey during the breeding season (leaf-roller caterpillars), and this, in turn, limits their response to conservation efforts.

Genetic structure and diversity of the capercaillie (Tetrao urogallus) population in Belarus in the context of de-lineation of two subspecies: major and pleskei

In the present article, an analysis of the genetic diversity and differentiation of the Belarusian capercaillie sub-populations from the range of two subspecies—Tetrao urogallus major and Tetrao urogallus pleskei—distinguished on the basis of morphological and behavioural (mating vocalization) criteria was carried out. The microsatellites were chosen as genetic markers. A total of 53 specimens were used for genetic analysis (23 specimens from the range of T. u. major and 30 specimens from the range of T. u. pleskei). In this study, we aimed at resolving the following questions: (1) Does the capercaillie subpopulation from the range of T. u. ma-jor in Belarus exhibit genetic isolation from the rest of the population in the country? (2) Should we consider the western subpopulation of the capercaillie in Belarus a management unit? Our data allows concluding that the genetic diversity of the studied capercaillie subpopulations is sufficiently high. The eastern subpopulation of the capercaillie is characterised by slightly higher values of all estimates of genetic diversity. A total of 35 unique alleles were detected in the studied capercaillie population. Of them, 10 alleles (29%) were discovered among the specimens sampled from the western subpopulation of the capercaillie. Genetic analysis for the presence of bottleneck events did not reveal any evidence of those in the demographic history of the studied Belarusian capercaillie subpopulations. Bayesian analysis of genetic structure has indicated the presence of two clusters, corresponding to the eastern and western capercaillie subpopulations in Belarus. The obtained ge-netic structure of the capercaillie population is also supported by the results of the factorial correspondence analysis. The results of genetic structure and diversity analysis indicate that the capercaillie population in Bela-rus possesses a degree of genetic differentiation on subpopulation level and a lack of clear isolation between the studied subpopulations. As recommendations for the conservation of the western subpopulation of the capercaillie in Belarus we propose to conduct genetic monitoring of the newly created population, as well as genetic analysis of the specimens used for breeding.

Parasite dynamics in North American monarchs predicted by host density and seasonal migratory culling.

Insect-pathogen dynamics can show seasonal and inter-annual variations that covary with fluctuations in insect abundance and climate. Long-term analyses are especially needed to track parasite dynamics in migratory insects, in part because their vast habitat ranges and high mobility might dampen local effects of density and climate on infection prevalence. Monarch butterflies Danaus plexippus are commonly infected with the protozoan Ophryocystis elektroscirrha (OE). Because this parasite lowers monarch survival and flight performance, and because migratory monarchs have experienced declines in recent decades, it is important to understand the patterns and drivers of infection. Here we compiled data on OE infection spanning 50years, from wild monarchs sampled in the United States, Canada and Mexico during summer breeding, fall migrating and overwintering periods. We examined eastern versus western North American monarchs separately, to ask how abundance estimates, resource availability, climate and breeding season length impact infection trends. We further assessed the intensity of migratory culling, which occurs when infected individuals are removed from the population during migration. Average infection prevalence was four times higher in western compared to eastern subpopulations. In eastern North America, the proportion of infected monarchs increased threefold since the mid-2000s. In the western region, the proportion of infected monarchs declined sharply from 2000 to 2015, and increased thereafter. For both eastern and western subpopulations, years with greater summer adult abundance predicted greater infection prevalence, indicating that transmission increases with host breeding density. Environmental variables (temperature and NDVI) were not associated with changes in the proportion of infected adults. We found evidence for migratory culling of infected butterflies, based on declines in parasitism during fall migration. We estimated that tens of millions fewer monarchs reach overwintering sites in Mexico as a result of OE, highlighting the need to consider the parasite as a potential threat to the monarch population. Increases in infection among eastern North American monarchs post-2002 suggest that changes to the host's ecology or environment have intensified parasite transmission. Further work is needed to examine the degree to which human practices, such as mass caterpillar rearing and the widespread planting of exotic milkweed, have contributed to this trend.

Long-Term Changes in the Wintering Population of the Dalmatian Pelican along the Black Sea-Mediterranean Flyway

Understanding spatiotemporal dynamics in wildlife populations is of paramount importance for their effective conservation, however longitudinal studies are relatively scarce for most animal groups. Waterbirds are an exception however, since midwinter surveys have been implemented in most areas of the world for over four decades. The Dalmatian Pelican Pelecanus crispus is a globally threatened emblematic wetland species of the Palearctic, with a wide distribution in Europe and Asia. Its global population is divided into three distinct groups that coincide with the Black Sea-Mediterranean Flyway, the Central Asian Flyway and the East Asian Flyway. In this study we used International Waterfowl Census data to assess long-term changes in the wintering population of the Dalmatian Pelican pertaining to the Black Sea-Mediterranean Flyway. We report national and regional population trends in SE Europe and Turkey and explore spatiotemporal patterns in the wintering numbers and distribution of the species in relation to climate variability during the last two decades. Our key findings suggest that during the past 30 years the abundance of wintering Pelicans increased across the entire study area. Within the eastern subpopulation this increase was most accentuated in the northern edge of the species' wintering distribution, which was associated with a local warming trend, and was coupled with a north-eastern shift in the distribution pattern, yet not driven by climate conditions. Other contributing factors, such as winter site fidelity, local food availability, finer scale climatic and habitat conditions, but also carry-over effects should be considered in future studies. Given the advancement of first laying dates in Dalmatian Pelicans in almost all breeding sites and the strict timing of IWC counts, we also propose the implementation of species-specific winter surveys, independently from IWC, to obtain a more thorough understanding of the dynamics of the Dalmatian Pelican's wintering population.

Does genetic variation on the shy–bold continuum influence carnivore attacks on people? Evidence from the brown bear

AbstractLittle is known about the heritable behavioural traits of attacks by large carnivores on people. During the last 30 years attacks by brown bears Ursus arctos on people in the Cantabrian Mountains of Spain have been disproportionately concentrated in the eastern subpopulation. Excluding factors such as the existence of a single unusually bold bear, a higher human population density, particular human activities promoting encounters, or clear habitat differences in the area of this subpopulation, we propose that a plausible explanation for the unbalanced geographical attack pattern is that this subpopulation, separated a century earlier from the western subpopulation, may harbour a higher proportion of bolder bears. In the absence of genetic analyses this explanation remains speculative, but supports the hypothesis that genetic variation on the shy–bold continuum may influence attacks of large carnivores on people.

Losing seasonal patterns in a hibernating omnivore? Diet quality proxies and faecal cortisol metabolites in brown bears in areas with and without artificial feeding.

Bears are omnivores particularly well-adapted to variations in the nutritional composition, quality and availability of food resources. Artificial feeding practices have been shown to strongly influence diet composition and seasonality, as well as to cause alterations in wintering and movement in brown bears (Ursus arctos). In this study, we investigated seasonal differences (hypophagia vs hyperphagia) in food quality of two brown bear subpopulations in the Polish Carpathians using faecal nitrogen (FN) and carbon (FC) estimates. The subpopulations inhabit areas that differ in artificial feeding practices: no artificial feeding occurs in the western subpopulation (Tatra Mountains), while artificial food targeted to ungulates is provided and used year-round in the eastern subpopulation (Bieszczady Mountains). We also compared these results with faecal cortisol metabolites (FCM) to explore how FN and FC correlate with the hypothalamic-pituitary-adrenal axis activity and if the seasonal patterns are apparent. We found that in Tatra Mts bears fed on significantly higher quality diet, as shown by FN and FC values, and had significantly higher FC levels in hyperphagia, when they accumulate fat reserves for wintering. The pattern in FCM levels for Tatra subpopulation followed the changes in energy intake during the seasons of hypo- and hyperphagia, while in Bieszczady Mts, the area with intensive feeding, no seasonal patterns could be observed. Artificial feeding practices may disrupt nutrient phenology and seasonality, relative to subpopulations with natural diets. We showed that the availability of human-provided foods may alter not only the overall dietary quality, but also hormonal patterns linked to seasonal nutritional requirements. Combining FN, FC and FCM proved to be a useful tool for reconstructing diet quality and related physiological patterns.

Not exodus, but population increase and gene flow restoration in Cantabrian brown bear (Ursus arctos) subpopulations. Comment on Gregório et al. 2020.

In a genetic study on brown bears (Ursus arctos) in the Cantabrian Mountains, Gregório et al. (2020) interpreted the asymmetrical gene flow they found from the eastern subpopulation towards the western one as an exodus of bears forced to flee from the eastern nucleus “with higher human disturbance and poaching”, concluding that connectivity may be operating as a means for eastern Cantabrian bears to find more suitable territories. In this reply, we maintain that the explanations of Gregorio et al. contradict the source-sink theory and we also present demographic data not considered by these authors showing that the eastern subpopulation is not declining, but persistently increasing. After reviewing the demographic and genetic studies published during the last 20 years, we conclude that the connectivity between the two subpopulations is operating as a route which allows the regular movement of males and the restoration of the gene flow across the whole Cantabrian population.

Consistent bear population DNA-based estimates regardless molecular markers type

Reliability of population size and density estimates is one of the most contentious issues when evaluating the conservation status of species. Non-invasive DNA monitoring, combined with spatially explicit capture-recapture approaches (SCR), is recurrently presented as a reliable procedure to achieve accurate, precise and feasible estimates. However, conservation practitioners frequently face the dilemma of which molecular marker type would perform better for their objectives. Here, using as case study the eastern subpopulation of the endangered Cantabrian brown bear, and the same dataset of non-invasive samples, we evaluated which molecular marker perform better (microsatellites vs. SNPs), and whether the selection of the marker could impact on estimates. Our results show similar posterior estimates for bear density and for the scale parameter, resulting in consistent population estimates, around 50 bears, regardless the molecular marker type selected, microsatellites: 48.4 (95%BCI = 33.8–67.3) or SNPs: 52.7 (95%BCI = 36.0–74.8). Using our dataset, we provide evidence for the importance of running several replicates for both microsatellites and SNPs when genotyping non-invasive samples, and how for the same number of molecular markers, microsatellites were statistically more powerful. The positive trend observed in small large carnivore populations requires the adaptation of monitoring approaches. The quality of indexes commonly used, such as the minimum annual counts of females with cubs of the year in our study case, may be more difficult to maintain over time as populations increase in size and range. We therefore recommend the implementation of a regular monitoring based on non-invasive DNA monitoring and SCR approaches.

Continent-wide population genomic structure and phylogeography of North America's most destructive conifer defoliator, the spruce budworm (Choristoneura fumiferana).

The spruce budworm, Choristoneura fumiferana, is presumed to be panmictic across vast regions of North America. We examined the extent of panmixia by genotyping 3,650 single nucleotide polymorphism (SNP) loci in 1975 individuals from 128 collections across the continent. We found three spatially structured subpopulations: Western (Alaska, Yukon), Central (southeastern Yukon to the Manitoba–Ontario border), and Eastern (Manitoba–Ontario border to the Atlantic). Additionally, the most diagnostic genetic differentiation between the Central and Eastern subpopulations was chromosomally restricted to a single block of SNPs that may constitute an island of differentiation within the species. Geographic differentiation in the spruce budworm parallels that of its principal larval host, white spruce (Picea glauca), providing evidence that spruce budworm and spruce trees survived in the Beringian refugium through the Last Glacial Maximum and that at least two isolated spruce budworm populations diverged with spruce/fir south of the ice sheets. Gene flow in the spruce budworm may also be affected by mountains in western North America, habitat isolation in West Virginia, regional adaptations, factors related to dispersal, and proximity of other species in the spruce budworm species complex. The central and eastern geographic regions contain individuals that assign to Eastern and Central subpopulations, respectively, indicating that these barriers are not complete. Our discovery of previously undetected geographic and genomic structure in the spruce budworm suggests that further population modelling of this ecologically important insect should consider regional differentiation, potentially co‐adapted blocks of genes, and gene flow between subpopulations.

Genetic analysis of African lions (Panthera leo) in Zambia support movement across anthropogenic and geographical barriers

The Luangwa Valley in eastern Zambia is a transverse offshoot of the Great Rift Valley system. This region appears to have an isolating effect as evidenced by suspected endemic subspecies, such as the Cookson’s wildebeest and Thornicroft’s giraffe. Recent mitochondrial DNA studies demonstrated that African lions in Zambia consist of two highly diverse eastern and western sub-populations. Herein, we report nuclear and mitochondrial DNA results from 409 lions that support this population substructure across Zambia but proposes only partial isolation of the Luangwa Valley with more movement between the populations than previously thought. Population assignment analysis identifies two populations with little evidence of admixture assigning lions to either the eastern or western sub-populations. A high occurrence of private alleles and clear evidence for a Wahlund effect further justify the presence of a highly structured population. But, while mitochondrial DNA analysis still shows little to no matrilineal gene flow (FST = 0.53) between sub-populations, microsatellite analysis suggests there is gene flow (FST = 0.04) with low but significant isolation-by-distance and an average of 6 migrants per generation. Evidence of isolation-by-distance is also found in factorial correspondence analysis with the Lower Zambezi National Park and eastern corridor clusters overlapping isolated clusters of the Luangwa Valley and western sub-population. From this evidence, the Luangwa Valley appears separated from the western sub-population with some dispersal through the southern regions of the eastern sub-population. Both the eastern and western sub-populations have high heterozygosity (0.68 and 0.69, respectively) and genetic diversity (0.47 and 0.50, respectively) values, indicative of genetically healthy populations.

Molecular characterization of Criniviruess involved in the etiology of cucumber yellowing disease in Riyadh region, Saudi Arabia

During the growing seasons 2014 and 2015, 134 cucumber and 103 weed samples showing typical yellowing diseases symptoms accompanied by chlorotic spots and interveinal chlorosis were collected from Riyadh region, Saudi Arabia. For this reason, RT-PCR was conducted for detection of two criniviruses, Cucurbit chlorotic yellows virus (CCYV) and Cucurbit yellow stunting disorder virus (CYSDV) which are implicated in cucurbit yellows disease. Results showed the presence of CCYV and CYSDV in cucumber samples in 61.1% and 19.4%, respectively, whereas 9% of the plants were contained mixed infection. In addition, four weed species were identified, for the first time, as alternative hosts of CCYV; whereas CYSDV was reported only in Malva parviflora plants. Partial nucleotide sequencing analysis was conducted using 13 CCYV and five of CYSDV isolates originated from cucumber and wild hosts. Both viruses exhibited low genetic diversity; however, phylogenetic analysis clustered the obtained CYSDV isolates in a separated group, named the “Eastern subpopulation”, while CCYV isolates were classified into subgroups IIa and IIb, among other published sequences, forming a different evolutionary lineage from group I, which contained an isolate from Iran.

제주도 큰발윗수염박쥐(Myotis macrodactylus)의 유전적 집단 구조와 계통 유연관계

본 연구는 미토콘드리아 DNA (mtDNA) cytochrome B (CYTB)와 NADH dehydrogenase subunit 1 (ND1) 유전자 서열의 다형성을 근거로 제주도 큰발윗수염박쥐 집단의 유전적 집단 구조와 계통 유연관계를 조사하는 데 목적이 있다. 동아시아 박쥐에서 CYTB 유전자 haplotype은 14개의 haplotype들이 발견되었고, ND1은 9개의 haplotype 들이 발견되었다. 집단별 haplotype의 분포는 지역-특이적인 양상을 보였다. ND1 haplotype 분석결과에서 제주도 집단은 4개의 haplotype을 나타내고, 한라산 소집단과 서부지역 소집단은 3개 haplotype을 나타내었으나, 동부지역 소집단에서는 제주도 전체에서 공통으로 발견되는 1개(Nd03)의 haplotype만 출현하였다. NJ tree에서 제주도 집단은 강원도 집단보다 일본 집단과 더 근연으로 확인되었다. 중국과 일본의 모계선조 계보 사이의 분화 시점은 0.789±0.063 MYBP으로 추정되었고, 제주도와 일본의 모계선조는 약 17만 년(0.168±0.013 MYBP) 전에 분리된 것 으로 판단된다. 제주도 집단은 적어도 5만 년 이전에 이주한 것으로 보인다. 또한 ND1 haplotype 분석결과는 제주도 집단이 이주 후에도 지역 내에서의 적어도 2회 이상의 유전적 분화를 겪었다는 것을 보여주고 있다. 본 연구 결과는 동아시아 큰발윗수염박쥐의 계통 유연관계를 이해하는 데 중요한 기초자료가 될 것이며, 향후 한반도의 남부와 중국, 러시아 등에서 시료 확보를 통해 집단 간 진화적 상관관계를 이해하는 데 필요한 설득력 있는 자료가 마련되어야 할 것이다. This study was carried out to reveal the genetic population structure of the Jeju Island population and the phylogenetic relationship of East Asian populations of the large-footed bat (Myotis macrodactylus) based on the genetic polymorphisms of mitochondrial cytochrome B (CYTB) and NADH dehydrogenase subunit 1 (ND1) gene sequences. A total of fourteen and nine haplotypes were found in the CYTB and ND1 sequences from East Asian bats, respectively. Haplotype distribution showed locality specific patterns. The results from ND1 haplotype analysis showed that the Jeju Island population has four haplotypes: the Mt. Halla and Western subpopulations have three ND1 haplotypes, but the Eastern subpopulation has just a single haplotype Nd03, which is commonly found on this island. The neighbor-joining (NJ) tree showed the closer relationship between Jeju Island and Japan rather than that between Jeju and Gangwon-do Province. The divergence time between the maternal ancestor lineages of Japanese and Chinese populations was estimated to be 0.789±0.063 MYBP. The secondary divergence between Jeju and Japanese bats was calculated about to be 0.168±0.013 MYBP. The Jeju population has immigrated to the island at least fifty thousand years ago. In addition, ND1 haplotype analysis suggested that the insular bats have experienced at least two further genetic differentiation events within this island. Consequently, these findings suggested that the results of this study may play a critical role in understanding the phylogenetic relationship among East Asian bat populations of M. macrodactylus. To prepare more explainable information on evolutionary correlation, analysis is still required to examine using expanded samples from China, Russia, and southern parts of the Korean Peninsula.

Genetic and demographic recovery of an isolated population of brown bear Ursus arctos L., 1758.

The brown bear Ursus arctos L., 1758 population of the Cantabrian Mountains (northwestern Spain) became isolated from other bear populations in Europe about 500 years ago and has declined due to hunting and habitat degradation. At the beginning of the 20th century, the Cantabrian population split into eastern and western subpopulations, and genetic exchange between them ceased. In the early 1990s, total population size was estimated to be < 100 bears. Subsequently, reduction in human-caused mortality has brought about an increase in numbers, mainly in the western subpopulation, likely promoting male-mediated migration and gene flow from the western nucleus to the eastern. To evaluate the possible genetic recovery of the small and genetically depauperate eastern subpopulation, in 2013 and 2014 we genotyped hair and faeces samples (116 from the eastern subpopulation and 36 from the western) for 18 microsatellite markers. Data from the annual count of females with cubs of the year (COY) during the past twenty-six years was used to analyze demographic changes. The number of females with COY fell to a minimum of seven in the western and three in eastern subpopulations in the biennium 1993–1994 and reached a respective maximum of 54 and 10 individuals in 2013–2014. We also observed increased bear dispersal and gene flow, mainly from the western to the eastern subpopulation. Of the 26 unique genotypes detected in the eastern subpopulation, 14 (54%) presented an admixture composition, and seven (27%) were determined to be migrants from the western subpopulation. Hence, the two separated and clearly structured subpopulations identified in the past currently show some degree of genetic admixture. This research shows the partial demographic recovery and a change in genetic composition due to migration process in a population of bears that has been isolated for several centuries.

Resolving the taxonomy, range and ecology of biogeographically isolated and critically endangered populations of an Australian freshwater galaxiid, Galaxias truttaceus

The spotted galaxias (or trout minnow), Galaxias truttaceus, is a species that is restricted to south-western and south-eastern Australia, but there has long been conjecture as to whether the geographically and Critically Endangered Western Australian populations represent a subspecies (Galaxias truttaceus hesperius). We provide evidence that Western Australian populations, on the basis of a combination of genetic, geographic and ecological criteria, should be considered an evolutionary significant unit, which merits management as a high conservation priority. Substructure at nuclear and matrilineal genetic markers is not suggestive of species-level divergence, but rather of discrete western and eastern Australian subpopulations with limited contemporary gene flow. In contrast to many eastern populations that are diadromous, all western populations are potamodromous. Adults live and spawn in riverine habitats and larvae drift downstream to coastal lakes, where they spend several months, before undertaking a distinct upstream recruitment migration as juveniles to colonise riverine habitats. Instream barriers that disconnect riverine and lentic habitats restrict distributional range and presumably affect reproductive success of Western Australian populations. Conserving the remaining populations in Western Australia will require ongoing efforts to reduce the impact of emerging threats, particularly those related to instream barriers, introduced species and reductions in water quantity and quality.

Diet of the Recovering Ohio Bobcat (Lynx rufus) with a Consideration of Two Subpopulations

Bobcats (Lynx rufus) are a native carnivore of Ohio, but by 1850 were extirpated or nearly so following pioneer settlement of the state. The first modern record of a bobcat in Ohio was an adult male killed in 1946. Distribution accounts indicate that population re- establishment began around 2000. Today the bobcat is protected, and verified sightings, camera surveys, and genetic analyses point to two subpopulations: a fast growing, self-sustaining eastern subpopulation, and a more slowly growing southern subpopulation. We evaluated stomach contents of 120 adult and subadult bobcat carcasses to help understand the disparity in subpopulation growth rates, and inform proper bobcat management. We identified prey species morphologically. We quantified prey species taken and converted their frequencies to caloric intake estimates. We calculated dry weight estimates of prey groups and compared them between bobcat age classes, sexes, regions, and across seasons. We examined regional diet differences further by calculating diet and condition indices. Eastern cottontail (Sylvilagus floridanus) occurred most often. White-tailed deer (Odocoileus virginianus) supplied the greatest caloric value. Small rodents and insectivores were the most common prey group. Adults consumed more, as defined by weight, meso-mammals and large rodents than subadults. Diet composition did not differ between sexes. Weight of large mammal intake differed significantly between winter and summer, being greater in winter. Diet composition and prey group weights did not differ regionally. Dietary niche breadth of the southern subpopulation indicated more even consumption of prey groups than the eastern, whereas food niche overlap between regions was high. The condition index of eastern and southern bobcats also did not differ. We present the first rigorous analysis of bobcat diet in Ohio, and infer that diet is not a likely driver of disparate subpopulation growth rates of this recovering species.

Estimating the population size of the endangered Cantabrian brown bear through genetic sampling

The Cantabrian brown bearUrsus arctospopulation can be seen as a paradigm in conservation biology due to its endangerment status and genetic uniqueness. Therefore, the need to obtain basic demographic data to inform management actions for conservation is imperative. Despite this, empirical data on the size and trends of the Cantabrian bear population are scarce. Here we present the first estimates of population size (Nc) and effective population size (Ne) of the whole Cantabrian brown bear population. We genotyped 270 non‐invasive samples collected during 2006 throughout the entire range of the population and subsequently identified 130 individuals. Different model estimators of Ncbased on capture—markrecapture (CMR) procedures were compared. The average for the best three models (Mh Chao, Mh Darroch and CAPWIRE TIRM) yielded a total estimate of Nc= 223 individuals (CI95%= 183–278) and Ne50 (CI95%= 36–75) providing an Ne/ Ncratio of 0.22. Estimates for the two subpopulations commonly recognized in the Cantabrian range were Nc= 203 (CI95%= 168–260) and Ne= 47 (CI95%= 36–70) for the western subpopulation and Nc= 19 (CI95%= 12–40) and Ne= 9 (CI95%= 8–12) for the eastern subpopulation. These data suggest that the Cantabrian brown bear population has increased recently, mainly in the western subpopulation, after a long period of decline and isolation which lead to the split of the population at the beginning of the 20th century. Population sizes in the early 1990s were thought to be only 60 individuals for the western subpopulation and 14 individuals in the eastern one. The efforts to improve conservation policies made since then have probably contributed, to some extent, to the population increase during the last couple of decades.

Temporal change in the spatial genetic structure of a sika deer population with an expanding distribution range over a 15‐year period

AbstractSince the 1980s, the sika deer (Cervus nippon Temminck, 1838) population of Hokkaido, Japan, has grown, resulting in range expansion. To assess the effects of this range expansion on the spatial genetic structure of the population, we compared subpopulation structures during 2 different periods (168 samples for 1991–1996, and 169 samples for 2008–2010), using mitochondrial DNA (mtDNA; D‐loop) and microsatellites (9 loci). The number of gene‐based subpopulations decreased across the 15‐year period; specifically from four to three subpopulations based on mtDNA, and from two to one subpopulation based on microsatellite DNA. The fusion of the two northern subpopulations caused the change to the mtDNA‐based structure, which might be explained by the dispersal of females from higher to lower density subpopulations. In comparison, the reason for the change in the microsatellite DNA‐based structure was unclear, because no significant genetic differentiation was observed between the two study periods. A stable mtDNA‐based structure was maintained in the north and central population separated by a west‐to‐east boundary, while a north‐to‐south boundary in eastern Hokkaido maintained stability in the eastern subpopulation versus all other subpopulations. The findings of this study demonstrate the importance of understanding gene flow within a structured population to implement effective management efforts; for instance, the culling of one subpopulation might not affect an adjacent subpopulation, because deer movement is limited between the subpopulations.

Genetic variability and evolution of broad bean wilt virus 1: role of recombination, selection and gene flow

Analysis of four genomic regions from 37 geographically diverse isolates of broad bean wilt virus 1 (BBWV-1) showed high genetic diversity in comparison to most plant viruses. Comparison of synonymous and nonsynonymous substitutions of the small coat protein gene (SCP) revealed negative selection for most amino acid positions. Phylogenetic analysis of SCP showed that some BBWV-1 isolates from distant geographical areas were genetically close, suggesting long-distance migration. Analysis of genetic differentiation revealed high gene flow between Spanish and Near Eastern subpopulations, which were separated from North-Central and South-Eastern European subpopulations. Finally, putative recombinant and reassortant genomes were also identified.

Isonymy analysis in a sample of parents of cystic fibrosis patients from Antioquia, Colombia

Cystic fibrosis (CTFR) is one of the most common autosomal recessive disorders in European descendants. Geographic distribution of CFTR gene mutations vary worldwide. The degree of isonimy was evaluated in a sample of parents with children affected by cystic fibrosis. Observed and expected isonimy as well as endogamy components (Fr, Fn, Ft, and the values α and B) were calculated for 35 parents of children diagnosed with cystic fibrosis. These parameters were calculated for both the total population of Antioquia Province and for an eastern subpopulation of Antioquia. The values obtained for Fr, Fn, Ft, α and B were 0.01, 0.007, 0.019, 268 and 0.44, respectively for the total population of Antioquia. For the eastern subpopulation, the values were 0.026, 0.0017, 0.027, 135 and 0.62. The most frequent last-names in the total sample (n=70) were Gómez (6%), Alzate (4%), and González (3.7 %), whilst for the eastern subpopulation (n=32) were Gómez (8%) and Marín (6%). A high percentage of last-names was shared, as is reflected in the isonimy values. Similarly, the presence of a reduced number of last-names in an important percentage of the population is reflected in the Fr values obtained for both analyses, which suggest homogeneity. Thus, it is expected a low number of CFTR mutations in the children from Antioquia with cystic fibrosis.

Contrasting Patterns of Genetic Diversity and Population Structure ofArmillaria melleasensu stricto in the Eastern and Western United States

ABSTRACT Armillaria mellea infects hundreds of plant species in natural and managed ecosystems throughout the Northern hemisphere. Previously reported nuclear genetic divergence between eastern and western U.S. isolates is consistent with the disjunct range of A. mellea in North America, which is restricted mainly to both coasts of the United States. We investigated patterns of population structure and genetic diversity of the eastern (northern and southern Appalachians, Ozarks, and western Great Lakes) and western (Berkeley, Los Angeles, St. Helena, and San Jose, CA) regions of the United States. In total, 156 diploid isolates were genotyped using 12 microsatellite loci. Absence of genetic differentiation within either eastern subpopulations (theta(ST) = -0.002, P = 0.5 ) or western subpopulations (theta(ST) = 0.004, P = 0.3 ) suggests that spore dispersal within each region is sufficient to prevent geographic differentiation. In contrast to the western United States, our finding of more than one genetic cluster of isolates within the eastern United States (K = 3), revealed by Bayesian assignment of multilocus genotypes in STRUCTURE and confirmed by genetic multivariate analyses, suggests that eastern subpopulations are derived from multiple founder sources. The existence of amplifiable and nonamplifiable loci and contrasting patterns of genetic diversity between the two regions demonstrate that there are two geographically isolated, divergent genetic pools of A. mellea in the United States.