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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. 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 États-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. [ABSTRACT FROM AUTHOR]

The comment by Romero and Kannada is presented as a critique of our previous work and suggests that our conclusions are in direct conflict with the historic whaling information reviewed in their paper. However, the critique is based on a misinterpretation of the geographical, temporal, and taxonomic focus of our previous work. The source of the putative conflict appears to stem from the misinterpretation that our results, focused solely on the impact of Basque whaling in the 16th and 17th centuries on the western North Atlantic right whale, were intended to be representative of all whaling of both right and bowhead whales throughout the North Atlantic. To demonstrate this, we briefly review our original results and conclusions and show that the information reviewed by Romero and Kannada does not challenge any aspect of our original work. As such, their comment is not a critique of our paper, but rather a brief review of the history of whaling in the North Atlantic. [ABSTRACT FROM AUTHOR]

The North Atlantic right whale, Eubalaena glacialis (Müller, 1776), is one of the world's most endangered large cetaceans. It is widely believed that Basque whalers caused the most dramatic decline of this species in the western North Atlantic during the early-16th and 17th centuries. Previous osteological analysis of 17 historic bones suggested that 50% of the Basque harvest consisted of right whales and 50% of bowhead whales, Balaena mysticetus L., 1758. This 50:50 ratio has been used to estimate pre-exploitation population size, which has subsequently formed the basis of recovery goals and plans for the North Atlantic right whale. Genetic analysis of 21 bones, 13 identified as right whales and 8 as bowhead whales through osteological examination, indicates that in fact only 1 bone was a right whale and 20 were bowhead whales. Additionally, preliminary microsatellite analyses of this specimen are not consistent with the hypothesis that whaling resulted in the low genetic variation found in this species today. These results differ from what would be expected based on any previous view of Basque whaling, and raise questions regarding the impact of Basque whaling on this species. [ABSTRACT FROM AUTHOR]

Genetic variation was examined for moose (Alces alces) from Riding Mountain, Isle Royale, and Pukaskwa national parks; northwestern, Nipigon, northeastern, and central Ontario; New Brunswick; and Newfoundland. The national parks were identified as maintaining potentially different local selection pressures due to the absence of hunting and the presence or absence of the parasite Parelaphostrongylus tenuis. Genetic variation was estimated using neutral DNA markers, assessed by multilocus DNA fingerprinting and five microsatellite loci, and the functional antigen binding region (ARS) (exon 2) of the major histocompatibility complex (MHC) gene DRB. There was discordance in the allelic diversity observed at the neutral loci compared with the MHC DRB locus in a number of populations. Ontario populations demonstrated higher levels of variability at the neutral loci and relatively low levels at the DRB locus. Conversely, the Isle Royale population has the lowest genetic variability, consistent with a historic small founding event, at the neutral DNA markers and relatively high variability at the MHC gene. Relatively high levels of genetic variation at the DRB locus were observed in protected park populations concomitant with the absence of white-tailed deer (Odocoileus virginianus) or the parasite P tenuis and an absence of hunting. Gene flow was observed among the neighboring geographic regions within Ontario, including Pukaskwa National Park, with evidence of isolation-bydistance among more distant regions within Ontario. The discordant patterns between DNA markers suggest that neutral DNA markers may not accurately reflect adaptive variation present at functional loci. [ABSTRACT FROM AUTHOR]