Salamander survival and growth cage experiment at the Coweeta Hydrologic Laboratory, Otto, NC

Climate change is predicted to alter biotic communities and, as a result, cause changes in ecosystem processes. Such predictions assume that future communities will lack species capable of compensating for the loss of other species. In southern Appalachian headwater streams, abundant larval Black-bellied Salamanders (Desmognathus quadramaculatus) represent a significant standing crop of nitrogen (N) and phosphorus (P). Desmognathus quadramaculatus are projected to be extirpated from the southern Appalachian highlands under most climate change scenarios, which would result in the loss of most salamander standing crop of limiting nutrients unless other species compensate for the loss of D. quadramaculatus biomass. Eurycea cirrigera, which has an abundant congener Eurycea wilderae already in the headwaters, and Gyrinophilus porphyriticus, which currently occurs in low densities in the headwaters, are projected to remain within southern Appalachian highlands. We used field cages to measure (1) the amount of compensatory survival and growth Eurycea would show in the absence of the larger, predatory D. quadramaculatus, and (2) whether replacement of D. quadramaculatus by G. porphyriticus, which is known to be a more efficient predator, would reduce Eurycea and total salamander biomass.