Forest removal and the cascade of effects corresponding with an Ozark Hellbender population decline

Abstract

Populations of the endangered Ozark Hellbender salamander (Cryptobranchus alleganiensis bishopi) in the North Fork of the White River (NFWR) in Missouri and other streams have declined precipitously in recent decades. Deforestation of the riparian and nearby upland habitat has corresponded with in-river habitat changes and other interacting stressors that coincide chronologically with the precipitous decline. We review the cascade of effects, including changes in water quality, benthic habitat, illegal and scientific harvesting, and introduced and reintroduced species occurrence that followed deforestation in the context of their impacts on hellbenders and relationship with other stressors such as climate change. In-river habitat changes since the 1960s include benthic microhabitat alterations associated with redistribution of gravel, siltation, and sedimentation and, in part, increases in nuisance vegetation, including periphyton. Deforestation of riparian and nearby upland habitats increased access and opportunities for human activities such as recreation, wildlife collection, and development. The subsequent degradation of stream habitat and water quality following deforestation reduced the carrying capacity for the NFWR Ozark Hellbender population and had negative consequences on population health.