<p dir="ltr">The Blanding’s Turtle (<i>Emydoidea blandingii</i>) is a species of conservation needs that ranges across the U.S Midwest and Northeast, and Ontario/Nova Scotia, Canada. The species has experienced several range expansions and contractions due to glacial dynamics and industrial landscape changes, which have led to population isolation and bottlenecks. Understanding genetic variation and population structure across the species’ geographic range is essential for conservation efforts to maintain and restore populations. While several regional studies have evaluated genetic variation in <i>E. blandingii</i>, there has been little population sampling across Michigan and limited attempts to directly compare genetic variation across extensively sampled populations within both its main range and disjunct segments in the Northeast U.S. In this study, I utilized 12 microsatellite loci to directly compare the genetic diversity of <i>E. blandingii</i> across 153 localities in a portion of the Great Lakes and the Northeast of the range. Additionally, 13 microsatellite loci were used to assess genetic diversity across 92 localities in Indiana, Ohio, and Michigan, including further sampling within Michigan. My findings confirmed higher genetic diversity within the Great Lakes compared to the Northeast and revealed greater genetic differentiation in the Northeast than in the Great Lakes. Population structure in both regions was influenced by distance (IBD) and watersheds, with a more pronounced effect in the Northeast. Using four different genetic clustering approaches (PCA, sPCA, STRUCTURE, and TESS3r), I identified three range-wide clusters, three within the Northeast, and three within the Great Lakes. Within the Great Lakes, estimates of effective population size (<i>N</i>e) were high at both the population and watershed level, although influenced by sample size. The long lifespans of <i>E. blandingii</i> likely contribute to high levels of genetic diversity, while post-glacial gene flow across the landscape has resulted in low to moderate levels of differentiation within the regions. This study highlights poorly understood population structure and differences in genetic diversity between regions. Although Great Lakes populations are less isolated and more genetically diverse than those in the Northeast, this does not suggest that they are secure. Both regions face potential genetic loss over the next century, requiring further management implications to mitigate any further decline.</p>

Bothrops bilineatus é uma das seis espécies presentes no grupo taeniatus, é reconhecida atualmente por duas sub-espécies: B. b. smaragdinus que se distribui pelo oeste Amazônico e B. b. bilineatus com distribuição disjunta pela Amazônia e Mata Atlântica. Este trabalho tem como objetivo testar a validade das duas sub-espécies com base em ferramentas moleculares, morfométricas, merísticas, hemipenianas e osteológicas, reconhecendo e delimitando as linhagens encontradas. Pretende-se ainda investigar as relações filogeográficas entre as populações ao longo da sua distribuição, analisando o tempo de divergência e os possíveis eventos associados a sua diversificação. Além disso, pretende-se comparar a variação molecular e hemipeniana de B. bilineatus com B. taeniatus (espécie filogeneticamente próxima) e as existentes nos outros grupos de espécies do gênero. Os resultados mostram que a variação genética e hemipeniana encontram se em diferentes níveis ao longo dos grupos de espécies em Bothrops, fornecendo informação relevante a nível intra e inter-específico. Foram recuperados seis clados estruturados para Bothrops bilineatus, representando quatro linhagens independentes e diagnosticáveis com base conjunta nos caracteres morfológicos, hemipenianos, osteológicos e moleculares: linhagem 1 - Amazônia central, basal as outras, linhagem 2 - Mata Atlântica+Escudo das Guianas externa às linhagens 3 e 4 Amazônia oeste parte sul e norte, respectivamente. Já para B. taeniatus quatro clados representando três linhagens foram recuperadas com bases nos caracteres moleculares e hemipenianos, porém se faz necessário buscar por mais caracteres morfológicos e osteológicos para melhor delimitar e diagnosticar as linhagens. As mudanças paleoclimáticas e geomorfológicas ocorridas na transição Terciário/Quaternário parecem ser os principais eventos a influenciar na diversificação das linhagens encontradas em Bothrops bilineatus e B. taeniatus / Bothrops bilineatus is one of six species in the taeniatus group, is now recognized by two subspecies: B. b. smaragdinus that distributes through western Amazon and B. b. bilineatus with disjunct distribution through Amazon and Atlantic Forest. This work aims to test the validity of these two sub-species, based on molecular, morphometric tools, meristic, osteological and hemipenial data, recognizing and delimiting lineages found. We also intend to investigate the phylogeographic relationships among populations throughout its distribution, analyzing the divergence time and possible events associated with it diversification. In addition, we intend to compare the molecular and hemipenial variation presented in B. bilineatus with B. taeniatus (phylogenetically close species) and those in the other groups of the genus. The genetic and hemipenial results show different levels of variation along the groups of Bothrops species, providing significant intra-and inter-specific information. Six clades structured to Bothrops bilineatus were recovered, representing four independent lineages diagnosable with joint based on morphology, hemipenial, osteological and molecular characters: lineage 1 - central Amazon, basal the others, lineage 2 - Atlantic Forest + Guayana Shield region recovered outside the sisters lineages 3 and 4 - western Amazon, southern part and western Amazon, northern part, respectively. As for B. taeniatus four clades representing three lineages were recovered with bases in molecular and hemipenial characters, however it is necessary to search for more morphological and osteological characters to better delimit and diagnose the lineages. Paleoclimatic and geomorphic changes in the transition Tertiary/Quaternary, probably are the major events influencing the diversification of lineages found in Bothrops bilineatus and B. taeniatus

Bothrops bilineatus é uma das seis espécies presentes no grupo taeniatus, é reconhecida atualmente por duas sub-espécies: B. b. smaragdinus que se distribui pelo oeste Amazônico e B. b. bilineatus com distribuição disjunta pela Amazônia e Mata Atlântica. Este trabalho tem como objetivo testar a validade das duas sub-espécies com base em ferramentas moleculares, morfométricas, merísticas, hemipenianas e osteológicas, reconhecendo e delimitando as linhagens encontradas. Pretende-se ainda investigar as relações filogeográficas entre as populações ao longo da sua distribuição, analisando o tempo de divergência e os possíveis eventos associados a sua diversificação. Além disso, pretende-se comparar a variação molecular e hemipeniana de B. bilineatus com B. taeniatus (espécie filogeneticamente próxima) e as existentes nos outros grupos de espécies do gênero. Os resultados mostram que a variação genética e hemipeniana encontram se em diferentes níveis ao longo dos grupos de espécies em Bothrops, fornecendo informação relevante a nível intra e inter-específico. Foram recuperados seis clados estruturados para Bothrops bilineatus, representando quatro linhagens independentes e diagnosticáveis com base conjunta nos caracteres morfológicos, hemipenianos, osteológicos e moleculares: linhagem 1 - Amazônia central, basal as outras, linhagem 2 - Mata Atlântica+Escudo das Guianas externa às linhagens 3 e 4 Amazônia oeste parte sul e norte, respectivamente. Já para B. taeniatus quatro clados representando três linhagens foram recuperadas com bases nos caracteres moleculares e hemipenianos, porém se faz necessário buscar por mais caracteres morfológicos e osteológicos para melhor delimitar e diagnosticar as linhagens. As mudanças paleoclimáticas e geomorfológicas ocorridas na transição Terciário/Quaternário parecem ser os principais eventos a influenciar na diversificação das linhagens encontradas em Bothrops bilineatus e B. taeniatus / Bothrops bilineatus is one of six species in the taeniatus group, is now recognized by two subspecies: B. b. smaragdinus that distributes through western Amazon and B. b. bilineatus with disjunct distribution through Amazon and Atlantic Forest. This work aims to test the validity of these two sub-species, based on molecular, morphometric tools, meristic, osteological and hemipenial data, recognizing and delimiting lineages found. We also intend to investigate the phylogeographic relationships among populations throughout its distribution, analyzing the divergence time and possible events associated with it diversification. In addition, we intend to compare the molecular and hemipenial variation presented in B. bilineatus with B. taeniatus (phylogenetically close species) and those in the other groups of the genus. The genetic and hemipenial results show different levels of variation along the groups of Bothrops species, providing significant intra-and inter-specific information. Six clades structured to Bothrops bilineatus were recovered, representing four independent lineages diagnosable with joint based on morphology, hemipenial, osteological and molecular characters: lineage 1 - central Amazon, basal the others, lineage 2 - Atlantic Forest + Guayana Shield region recovered outside the sisters lineages 3 and 4 - western Amazon, southern part and western Amazon, northern part, respectively. As for B. taeniatus four clades representing three lineages were recovered with bases in molecular and hemipenial characters, however it is necessary to search for more morphological and osteological characters to better delimit and diagnose the lineages. Paleoclimatic and geomorphic changes in the transition Tertiary/Quaternary, probably are the major events influencing the diversification of lineages found in Bothrops bilineatus and B. taeniatus

Amphibians globally are declining with roughly a third facing extinction due primarily to threats linked to human impacts. One way in which this is being combated is by captive breeding programs. Nordens Ark in Sweden, in collaboration with other organizations, is attempting to breed one of the most threatened frogs for future reintroduction to the wild. The mountain chicken (Leptodactylus fallax) has unique characteristics related to its reproduction which make it challenging to breed successful offspring. Using Nordens Ark’s data on environmental conditions within breeding enclosures, this study attempts to determine which extrinsic factors are having the most influence on reproduction, in order to increase the success of the captive breeding program. Multiple linear regression analysis and model simplification using Stepwise regression and Akaike information criterion (AIC) were performed in order to determine which explanatory variables had the most influence in relation to foam nests. A reduced model with significant values for explanatory variables was deemed the best model based on the dataset. Of the 14 environmental variables tested, minimum temperature after nest construction had the most influence on foam nest length. When compared to wild habitats, temperatures within enclosures may be too high or lack seasonal cyclical patterns. Barometric pressure and humidity also had influence on foam nests, but the relationships between these environmental conditions is difficult to parse. Food supplements were also a significant factor and suggest that lack of vitamins or nutrients can have a negative effect on reproductive success. Ensuring the optimal conditions can be difficult for captive breeding programs, especially as amphibians are under-represented and face biases in conservation and research.

As replacement and removal of undersized culverts gains momentum as an effective technique for restoring natural stream flows and removing fish passage barriers, it is important to evaluate the benefits of these efforts on the in-stream and adjacent riparian habitat for other species of potential concern. This study compares stream-associated amphibian (SAA) occurrence in streams adjacent to different road crossing structures on unpaved forest roads in the Wilson River watershed located within the Tillamook State Forest, Oregon. Surveys were conducted at road crossing structures for three taxa of SAA; Pacific giant salamander (Dicamptodon tenebrosus), coastal tailed frog (Ascaphus truei), and Columbia torrent salamander (Rhyacotriton kezeri). Statistical models were created to analyze the effect of habitat variables on SAA occupancy, and determine whether those variables changed relative to road crossing structures. Results showed that coastal tailed frog occupancy was positively associated with dissolved oxygen and crayfish presence, negatively associated with longitude, and had a slight quadratic relationship to channel confinement. Because all sites were highly saturated with oxygen, percent dissolved oxygen was likely a surrogate for one or more other covariates, such as in-stream habitat or substrate size. Detection rates of Pacific giant salamander were too high and detection rates of Columbia torrent salamander were too low to provide reliable models, but they did provide some insight into the factors affecting occupancy in the study area, including information about their interactions with road crossing structures. Occupancy rates of Pacific giant salamanders in the study area appear to be unaffected by road crossings, fish passable or otherwise. Conversely, torrent salamanders seemed to be mostly absent from the study sites altogether, but based on the one stream where they were detected, they are not excluded from occupying fish barrier culvert sites. Top weighted habitat covariates, including dissolved oxygen, channel confinement, crayfish and fish presence, and flow constriction are all indicators of disturbance that can be linked to road crossings. Although the size and structure of road crossings did not prove to significantly influence SAA occupancy, indicators of stream disturbance that can be related to road crossings were included in the best models for predicting occupancy, demonstrating the importance of reducing disturbance related to road crossings on streams.