Results
In total we compiled 5010 roadkill events from both systematic surveys and non-systematic studies (citizen science and other studies). Most of these (4244) had accurate geographic information with GPS coordinates taken at the site where roadkill was found. In total, roadkill records represented at least 454 wildlife species. Most were non-threatened fauna, but two are listed as Critically Endangered, four as Endangered, nine as Vulnerable, and six as Data Deficient by the IUCN (IUCN, 2022). Nearly all records were tetrapods with relatively similar proportions of records in the four classes but marked differences in the diversity of species identified. Birds had the highest number of roadkills: 1428 (28.50% of the total) representing 200 species, followed by reptiles with 1356 records (27.06%) from 123 species, 1326 records (26.47%) for 94 mammalian species, and 895 records (17.86%) for 36 amphibian species. We obtained five records via citizen science (0.1%) for two invertebrates classes, Malacostraca and Clitellata. This vertebrate bias does not reflect lack of roadkill among invertebrates but detectability and the most common target groups of systematic surveys and citizen science efforts.
Although amphibians had the lowest number of records, the cane toadRhinella marina was the most roadkilled species with 532 records (more than half of the records for amphibians). The second and third most recorded species were two marsupials: the common opossumDidelphis marsupialis (n=454) and the Andean white-eared opossumDidelphis pernigra (n=336). A bird, the yellow warblerSetophaga petechia (n=193), and a reptile, the common green iguana Iguana iguana (n=126) were the fourth and fifth most roadkilled species.