NATURAL HISTORY AND CONSERVATION STATUS OF CROTALUS PYRRHUS COPE, 1866 (SQUAMATA: VIPERIDAE) FROM ISLA EL MUERTO, GULF OF CALIFORNIA, MEXICO

Abstract

The species of rattlesnakes that inhabit the islands of the Gulf of California in México represent a group of vertebrates that are endangered (García-Padilla et al., 2018). The main pressures they face are invasive species and illegal capture for commercialization (Mellinck, 1995). Presently, aspects of natural history and conservation status for many populations of various species still remain virtually unknown to science. During May-June of 2009, we visited Isla El Muerto where there exists an insular population of the rattlesnake Crotalus pyrrhus (Meik et al., 2015). The taxonomic status of this species has been discussed, but almost nothing has been published about its ecology and natural history. Here, we present new data concerning the distribution, relative abundance, and conservation status of this insular population of this species. We established that this species might be less abundant than previous authors mentioned; the estimated relative abundance we obtained is 0.22 snakes/hour. Also, we identified that the conservation status provided by Mexican (NOM-059 SEMARNAT, 2019) and international (IUCN) systems needs to be revised and modified to allocate this species to a higher level of protection. We believe that this information can be used as a basis for promoting and achieving the effective protection and conservation of this population of C. pyrrhus and its habitat for perpetuity