Road features shape taxon-specific wildlife roadkill patterns in the western Colombian Caribbean

Source abstract

Abstract Wildlife roadkill represents a major direct threat to many species, affecting population dynamics, and in some cases driving species toward extinction. Although roadkill has been widely documented in Colombia, studies in the Caribbean Region, which encompasses key vulnerable ecosystems such as the Tropical Dry Forest (TDF), remain scarce. Here, we assessed whether road characteristics influence the taxonomic composition of vertebrate roadkill on peri-urban roads in the department of Córdoba. We conducted systematic bicycle surveys along three inter-municipal roads over a three-month period during the dry-to-wet transition season, recording species identity and local road characteristics, including artificial lighting near houses, fences, water bodies, traffic signals, and wildlife crossings. We recorded 317 roadkill events, most of which were identified to species (217), with reptiles representing the largest proportion of records, followed by amphibians, mammals, and birds. The taxonomic composition of roadkill records was associated with local road characteristics. Mammal records were more likely on illuminated road sections and in the absence of fences, but less likely near water bodies. Bird records were less likely in the absence of fences and in the presence of wildlife crossings. Amphibian records were more likely in the presence of pole fences and less likely on illuminated road sections, whereas reptile records were more likely near water bodies. These findings indicate that local road characteristics shape the relative representation of vertebrate groups among roadkill records in peri-urban TDF landscapes. Mitigation measures are necessary to reduce mortality and preserve ecosystem functionality.