Rock crevice morphology and forest contexts drive microhabitat preferences in the Green Salamander (Aneides aeneus)

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.

Combining Citizen Science with Traditional Biotic Surveys to Enhance Knowledge Regarding the Natural History of Secretive Species

The Green Salamander (Aneides aeneus) is a secretive, arboreal cliff specialist distributed discontinuously across the southern and central Appalachian Mountains, USA. While intensively studied in some parts of its range in the Appalachian Plateau and Blue Ridge Provinces, the distribution of A. aeneus is still poorly understood, particularly in the Cumberland Mountains physiographic province of the Appalachian region. This data deficiency is partly the result of a lack of formal historic surveys across this region, coupled with a high amount of privately owned land that is inaccessible to traditional biotic surveys. We used a combination of citizen science efforts and traditional field surveys to investigate the distribution and status of A. aeneus across the Cumberland Mountains of southwestern Virginia, USA. Local landowners and outdoor recreation enthusiasts reported a relatively high rate of encounters with A. aeneus, verifying the species’ persistence at four historic localities and leading to the discovery of 36 previously unknown populations. Although we are cautious about making inferences about the true conservation status of A. aeneus across this region given the scarcity of current data, these findings suggest that the distribution of A. aeneus in Virginia has been vastly underestimated and that expanded monitoring programs are needed to further ascertain this species’ status. More broadly, our results illustrate the utility of coupling public initiatives with more traditional field surveys to expand the biogeographic knowledge of secretive, difficult-to-study amphibian species.

Woody and arboreal habitats of the Green Salamander (Aneides aeneus) in the Blue Ridge Mountains

The green salamander (Aneides aeneus) is primarily considered a rock crevice dwelling species. However, many early observations from Kentucky, Tennessee, Virginia, and West Virginia report A. aeneus taken from woody and arboreal habitats. There have been only four published records of A. aeneus using such habitats within the Blue Ridge Disjunct population of southwest North Carolina, northeast Georgia, and northwest South Carolina, and no records since 1952. Here I report two personal observations of A. aeneus using arboreal habitats in North Carolina. Additionally, I report nine observations, made by others, of A. aeneus using woody, arboreal, or otherwise non-rock-crevice habitats in North and South Carolina, including the first non-rock-crevice A. aeneus nesting record for the Blue Ridge. I also speculate that woody and arboreal habitats play a much larger role in the life-history of A. aeneus than generally thought, and that the rarity of A. aeneus is linked to the loss of American Chestnut and old-growth forests.