Meeting Abstract
Green salamanders, Aneides aeneus, are known to occur in crevices of rock cliffs that are humid but not wet. Postural adjustments and a high tolerance to desiccation or critical activity point (CAP) allow A. aeneus to respond to changes in moisture conditions that may arise in home crevices or transcient crevices. A high CAP of 36.7% found in A. aeneus from southeastern KY combined with inherent behavioral adjustments such as coiling of the body, aligning the tail along the body and flattening the body to the substrate all reduce body surface exposure and slow the dehydration rate and extend the time to reach CAP. During drought or dry conditions, A. aeneus may remain in home crevices longer and forage from crevices for short periods. A high CAP may allow them to tolerate some loss of body water (8-12%) which may be rehydrated as humidity levels rise overnight and some water condenses on rock cliffs. Also, conditions of extended rainfall resulting in water standing in crevices may subject some A. aeneus to over-hydration. In ten instances (equally divided in lab and field), individual salamanders were observed in postures where the limbs were raised high and the head and tail were raised off the substrate thereby significantly reducing exposure of the skin to wet substrates. One salamander shifted to an alternate posture in which all four feet were in contact with the substrate with limbs extended, and the mid-body arched above the substrate. Slight changes in posture may provide for fine control of dehydration or rehydration rates to optimize body water economy or content. Postural adjustments may allow terrestrial salamanders, such as A. aeneus, to remain in home crevices thereby reducing exposure to predation.
