First record of amphibian mortality associated with the fungus <em>Batrachochytrium dendrobatidis</em> in Catalonia (NE Spain)

Abstract

We report the first cases of mortality in anurans associated with the presence of the fungus Batrachochytrium dendrobatidis at four different localities from Catalonia (NE Iberian Peninsula, Spain). All cases were confirmed by both molecular techniques and histology. The infected individuals were two Mediterranean painted frogs (Discoglossus pictus) from Girona province found in 2018 and 2020, one Iberian waterfrog (Pelophylax perezi) from Tarragona province found in 2018, and one European common frog (Rana temporaria) from Barcelona province found in 2019. This is the first time that mortality associated with this pathogen has been confirmed in D. pictus and P. perezi. The role of the fungus as an agent possibly leading to death, in association with other external environmental factors, is discussed. These findings could suggest a recent increase of the incidence of this disease in the region. Some of these cases are particularly worrying because of their occurrence close to sites where some endemic amphibian species with extremely reduced distributions inhabit.

Introduced Mediterranean painted frogs (Discoglossus pictus) are possible supershedders of the fungus Batrachochytrium dendrobatidis in Catalonia (NE Spain)

“…Nowadays, it is present in a broad and continuous coastal strip from Besiers (France) to Sant Celoni (Catalonia, NE Spain), with several growing populations outside this range, probably due to accidental translocations apart from natural dispersal (e.g., Montpellier and Jacou in France; Llobregat Delta, mountains of Collserola and Gar- Catalonia;Garcia-Salmerón et al, 2022). The species is a known carrier of the pathogenic cutaneous fungus Batrachochytrium dendrobatidis (Bd) (Montori et al, 2019), and its chytridiomycosisrelated mortality has been recently recorded (Martínez-Silvestre et al, 2021). Here we report six recent episodes involving mortality or dying specimens that occurred in Catalonia, two of them in new dispersal areas of the species (locations 1 and 6; table 1, fig.…”