Itraconazole as a Successful Treatment to Manage Batrachochytrium dendrobatidis Outbreaks in ex-situ Frog Colonies in Argentina: Dose and Schedule for Pleuroderma somuncurense

Abstract

The El Rincon Stream Frog, Pleurodema somuncurense, is a Critically Endangered species that inhabits permanent hot springs and the warm headwaters of the Valcheta Stream, a watercourse located on the northern edge of the Somuncura Plateau (Patagonia, Argentina) (IUCN 2021). In 2015, an ex-situ assurance colony of this frog was established at the La Plata Museum (Buenos Aires, Argentina) as part of a conservation program to recover wild populations of this species. Since 2016, several reproduction events of this frog have occurred in the ex-situ facility (Velasco 2018). The high productivity associated with these reproductive events resulted in hundreds of froglets in good health, allowing a reintroduction program to be initiated aimed at reestablishing extinct populations of this species in the wild. Since then, eight successful reintroductions have been made in four restored habitats (Martínez Aguirre et al. 2019; FPK, pers. observ.). It is important to mention that during all the years of success of the ex-situ colony, only two massive mortality events occurred, both related to failures in the heating and cooling system. The first mortality event occurred in 2017 when a significant increase in temperature caused the sudden death of 15 adult frogs. The second case is described in this work.