Catalonia's Pyrenean brook newt populations healthy
Researchers from the UAB have ruled out the presence of chytrid fungi in the Pyrenean brook newt thanks to a study conducted with 642 samples. Nevertheless, the detection of this fungi in midwife toads living in the vecinity of where the newts are found, makes researchers highlight the importance of continuously monitoring the health of Pyrenean amphibians.
Researchers from the Wildlife Conservation Medicine (WildCoM) group at the Universitat Autònoma de Barcelona (UAB) conducted a study to verify whether two pathogen fungi, Batrachochytrium dendrobatidis and Batrachochytrium salamandrivorans, could be found among the Pyrenean brook newt populations of Catalonia. These two fungi can cause chytridiomycosis in amphibians, a global disease due to animal trade and human mobility which has caused the extinction of several amphibian species throughout the world. In the Iberian Peninsula, chytrid fungi have been found mainly at high altitudes.
The study included the sampling of 642 Pyrenean brook newts and 495 specimens belonging to five different amphibian species living in the same region: the palmate newt, the salamandra, the Pyrenean frog, the common toad, and the midwife toad. The study was conducted in 15 areas of three natural parks (Cadí-Moixeró, Capçaleres del Ter i del Freser, and Alt Pirineu).
“None of the newts tested positive for either of the two chytrid fungi in the samples analysed, so we can say that the Pyrenean brook newt populations in Catalonia are free from these pathogens”, explains Òscar Cabezón, researcher at the Department of Animal Medicine and Surgery and director of this project. “We detected B. dendrobatidis only at the easternmost point of the Pyrenees, at the limits of where the newts are distributed, and in another species, the midwife toad”, he adds.
“We confirmed that the amphibians living in the areas studied had no apparent health problems. Nevertheless, the detection of one of the two fungi in one point of the Pyrenees does highlight the importance of continuously monitoring these populations, to detect any possible spreading of the pathogen and future health problems”, project researcher Maria Puig Ribas points out.
The study served to create a bank of samples which will be used in future research projects, “essential in detecting new pathogens when they appear”, the researchers state. The next step in this study will be defining new objectives focused on conserving the species. The researchers are also conducting population studies of both the Pyrean brook newt and other amphibians.