The Puerto Rican crested toad (Peltophryne lemur) is currently composed of a single wild population on the south coast of Puerto Rico and two captive populations founded by animals from the northern and southern coasts. The main factors contributing to its decline are habitat loss, inundation of breeding ponds during storms, and impacts of invasive species. Recovery efforts have been extensive, involving captive breeding and reintroductions, habitat restoration, construction of breeding ponds, and public education. To guide future conservation efforts, genetic variation and differentiation were assessed for the two captive colonies and the remaining wild population using the mitochondrial control region and six novel microsatellite loci. Only two moderately divergent mitochondrial haplotypes were found, with one fixed in each of the southern and northern lineages. Moderate genetic variation exists for microsatellite loci in all three groups. The captive southern population has not diverged substantially from the wild population at microsatellite loci (F ST = 0.03), whereas there is little allelic overlap between the northern and southern lineages at five of six loci (F ST [ 0.3). Despite this differentiation, they are no more divergent than many populations of other amphibian species. As the northern breeding colony may not remain viable due to its small size and inbred nature, it is recommended that a third breeding colony be established in which northern and southern individuals are combined. This will preserve any northern adaptive traits that may exist, and provide animals for release in the event that the pure northern lineage becomes extirpated.

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Almost all turtle species nest in terrestrial environments and maternal site selection represents a critical component of nest success. Females use cues in the current environment to predict the future conditions for embryo development. However, in disturbed landscapes, current and future conditions may not be correlated. We compared selection of nest sites by Blanding’s Turtles (Emydoidea blandingii (Holbrook, 1838)) in a (relatively undisturbed) park and a (heavily disturbed) agricultural landscape in Ontario, Canada, using field measurements and satellite imagery. Environmental variables were compared using logistic regression and Akaike’s information criterion (AIC) based on data measured at nest (presence) and random (pseudoabsence) locations. Specific environmental variables associated with site selection differed between study areas. Most notably, NDVI (normalized difference vegetation index, a proxy for vegetation cover) increased significantly during the year at the agricultural locale, corresponding with the growth of planted fields. No parallel change was observed at the park locale where canopy cover remained more consistent. An increase in vegetation cover may alter nest temperatures and soil moisture. Combined with the unpredictability in timing of crop sowing and harvesting, findings suggest that nests in agricultural fields may act as ecological sinks and that other species nesting in similarly altered habitats may be subjected to the same threats.

We have isolated and characterized 17 tetranucleotide microsatellite loci for Blanchard's cricket frog ( Acris crepitans blanchardi ), an anuran common in the central USA. Sixteen loci were organized into four multiplex amplification reactions. These loci were highly polymorphic when screened in 55 individuals from two distant populations, with 11-48 alleles per locus (average = 24.8). Observed and expected heterozygosities ranged from 0.18 to 0.97 and from 0.17 to 0.96, respectively. Nine loci were also polymorphic in Acris crepitans crepitans , with seven polymorphic in Acris gryllus . Five loci amplified in all three taxa. These loci will be useful for population-and species-level investigations of this widespread group.

Peripheral populations of widespread species are often considered unworthy of conservation efforts; however, they may be adapted to the conditions found at the range edge and are therefore important to the future evolutionary potential of the species. Blanchard's Cricket Frog (Acris blanchardi Harper, 1947) is widespread and abundant throughout the central United States, but is declining at the northern edge of its range. To assess the distinctiveness and conservation value of the northern populations, we investigated the spatial genetic structure and phylogeography of this anuran using mitochondrial control region sequences. Analysis of 479 individuals identified 101 haplotypes, with relatively low nucleotide diversity. Two moderately divergent clades were found. One was restricted to the southwest, which was probably a refugium during the Pleistocene, whereas the other occurred primarily across the north and is likely the result of postglacial colonization. The genetic distinctiveness of northern populations indicates the potential for adaptive differences of individuals in this region relative to those in the south. We therefore conclude that conservation efforts are justified for the declining northern populations of Blanchard's Cricket Frog, and we use the spatial genetic structure described here to develop specific recommendations for this anuran.Résumé : On considère souvent que les populations périphériques d'espèces à large répartition ne valent pas les efforts de conservation; elles peuvent, cependant, être adaptées aux conditions qui prévalent à la périphérie de l'aire de répartition et ainsi être importantes pour le potentiel évolutif futur de l'espèce. La rainette grillon de Blanchard (Acris blanchardi Harper, 1947) est une espèce largement répandue et abondante dans tout le centre des É tats-Unis, mais elle est en déclin à la marge nord de son aire de répartition. Afin d'évaluer la particularité et la valeur de conservation des populations nordiques, nous avons étudié la structure génétique et la phylogéographie de cet anoure à l'examen des séquences de la région de contrôle mitochondriale. Une analyse de 479 individus a révélé l'existence de 101 haplotypes, avec une diversité relativement basse des nucléotides. Il existe deux clades à divergence moyenne. L'un est restreint à la région sud-ouest, qui a probablement servi de refuge au pléistocène, alors que l'autre est surtout répandu dans tout le nord et résulte vraisemblablement de la colonisation postglaciaire. La différenciation génétique des populations nordiques laisse croire à un potentiel de différences adaptives chez les animaux de cette région par rapport aux animaux du sud. Nous concluons qu'il est justifié de déployer des efforts de conservation pour les populations nordiques déclinantes de la rainette grillon de Blanchard; nous utilisons la structure génétique spatiale décrite ici pour mettre de l'avant des recommandations spécifiques au sujet de cet anoure.[Traduit par la Rédaction]