Projected population persistence of eastern hellbenders (Cryptobranchus alleganiensis alleganiensis) using a stage-structured life-history model and population viability analysis

摘要: Abstract The population of eastern hellbenders (Cryptobranchus alleganiensis alleganiensis) in the Blue River, Indiana has undergone a dramatic decline over last decade. Recruitment these declining populations been negligible, and are now composed almost entirely older age classes (upwards 20 years old). Given this decline, it is imperative to assess impacts demographic patterns on growth long-term stability. Therefore, we developed stage-structured, life-history model examine effects varying levels egg, juvenile, adult survivorship abundance, recruitment, projections. We performed sensitivity analysis determine which parameters have greatest potential increase/stabilise hellbender growth. Finally, conducted viability probability extinction associated with management strategies. For Indiana, adults (especially females) most important component viability. Sensitivity elasticity analyses Lefkovitch matrix revealed that survival egg/larvae stages for focused efforts. Indeed, had highest reproductive value model. Increasing by as little 20% corresponded turning point at ceased increased abundance (28% egg/larvae). importance transition from subadult (transitional element) was identified an additional factor maintaining based relatively long period spent stage (seven females). A likelihood projected time frame under no (∼25 complete extirpation; extinction = 1) if efforts such captive rearing headstarting undertaken (probability