Discovery of underground shelters occupied by the Chacoan Marsh Rat after massive wildfires in Pantanal, Brazil

Abstract

The drought and wildfires that swept through Pantanal, the major South American wetland, in 2020 severely impacted the local biota.  The resilience of native species to these types of extreme events remains largely unknown.  During post-wildfire surveys at recently affected sites, we found three burrows containing the semi-aquatic Chacoan marsh rats (Holochilus chacarius).  We also found a callichthyid catfish (Hoplosternum sp.) and a trichodactylid crab (Dilocarcinus pagei) alive and co-habiting one of the burrows with H. chacarius.  We report for the first time the use of underground structures with a flooded chamber by the Chacoan marsh rat.  We discussed the importance of these burrows for post-fire survivorship and whether they may serve as shelters for H. chacarius and other species against wildfires and drought, under the light of previous studies with other taxa.