Identifying congruence in the geographical position of lineage breaks and species range limits across multiple taxa is a focus of the field of comparative phylogeography. These regions are biogeographical hotspots for investigations into the processes driving divergence at multiple phylogenetic levels. We used spatially explicit statistical methods to identify these regions for amphibians across the United States. Significant clustering occurred in the Appalachian Mountains and in the general area of Alabama - a region underappreciated as an important amphibian hotspot. When the orders Caudata and Anura were examined separately, spatial clustering was still found in Alabama for both. However, in Caudata the Appalachians and California were also important, and for Anura, the Great Lakes region was highlighted. When species richness was statistically controlled, cluster hotspots shifted out of Alabama and the Appalachians and moved to broader swaths of the Great Lakes region, southwestern United States and California. The exact location of particular suture zones is probably a result of complex interactions between historical and ecological factors including physiography, climate and distance from glacial refugia. These contact zone and phylogeographical break hotspots are ideal arenas in which to test alternative speciation hypotheses and examine the extent of reproductive isolation using novel, integrative approaches combining modern methods in statistical phylogeography, ecological niche modelling and genomics.

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The identification of small habitat features embedded within forest ecosystems is a challenge for many wildlife inventory and monitoring programs, especially for those involving rock outcrop specialist taxa. Rock outcrops are often difficult to remotely detect in dense Appalachian hardwood forests, as most outcrops remain hidden under the forest canopy and therefore invisible when relying on aerial orthoimagery to pinpoint habitat features. We investigated the ability for light detection and ranging (LiDAR) point cloud data to identify small rock outcrops during the environmental assessment phase of a proposed management project on the Jefferson National Forest in Virginia, USA. We specifically compared this approach to the visual identification of rock outcrops across the same area using aerial orthoimagery. Our LiDAR-based approach identified three times as many rock outcrop sites as aerial orthoimagery, resulting in the field-verification of four times as many previously-unknown populations of green salamanders Aneides aeneus, a rock outcrop specialist amphibian of high conservation concern, than would have been possible if relying on aerial orthoimagery alone to guide surveys. Our results indicate that LiDAR-based methods may provide an effective, efficient, and low-error approach that can remotely identify below-canopy rock outcrops embedded within Appalachian forests, especially when researchers lack pre-existing knowledge of local terrain and the location of habitat features.

Herpetofauna are frequently cited as ideal indicators for environmental and restoration monitoring due to their importance to ecological functioning, dominance of vertebrate biomass, and sensitivity to environmental change. Despite this relevance, herpetofauna have yet to be fully integrated into comprehensive, community-scale restoration monitoring methodologies. We tested the applicability of one such method, abundance-biomass comparisons (ABCs), to monitoring restoration success in a longleaf pine ecosystem currently undergoing restoration via prescribed burning. W statistics (a metric of environmental perturbation) for herpetofaunal assemblages in longleaf pine stands managed under varying fire intervals closely tracked forest succession from recently burned longleaf pine stands to those characterized by longer times since last burn and high levels of hardwood encroachment. Our results suggest that ABCs may be an applicable method for terrestrial restoration monitoring that encompasses entire faunal assemblages and allows for generality in restoration or disturbance response. We emphasize, however, that applications of this method and others need to take into account the specific ecological characteristics of study organisms and the natural history of study sites to avoid incorrect interpretations of disturbance response and inappropriate management recommendations.

Little is known about how vertical rock habitats are selected by organisms in forest ecosystems. Multiple lungless salamanders use rock outcrops in the Appalachian Mountains of eastern North America, with Green Salamanders (Aneides aeneus (Cope and Packard, 1881)) showing the strongest associations as an outcrop specialist. Although previous work has identified environmental correlates of rock face and arboreal habitat use in this species, it remains to be known if and how Green Salamanders select crevice refugia as a function of both outcrop morphology and the context of outcrops within the surrounding forest. We performed an intensive survey of an abundant Green Salamander population on Virginia’s Appalachian Plateau to examine which features of vertical habitats are associated with salamander occupancy. Occupancy was highest in deeper rock crevices closer to surrounding trees, a likely consequence of arboreal behavior and the ability for crevice refugia to modulate the surrounding microclimate. Although uncertainty exists with regards to the generality of these results across the species’ range, our results underscore linkages between embedded rock outcrop habitats and their surrounding forest contexts for amphibians. Our results also provide a model of Green Salamander habitat associations that may be valuable to efforts to elucidate its geographic distribution.