How genetic tools can help crocodilians' management and governance

Abstract

The applications of genetic tools for crocodilians? management and governance can be done at two levels: intra- and interspecifc. The following intraspecifc processes can be investigated by the use of genetic tools: mating system, parental care, and dispersal pattern, potentially useful for biological conservation; identifcation of ?problem? individuals involved in humans and livestock predation,potentially useful for control; and the identifcation of reproductive females in monitoring programs based on nest identifcation and counting. As management of endangered species implies in the necessity for the increase of depleted populations, two possible consequences should be considered: loss of genetic variability and a change on the selective pressures. The former has been usually monitored using genetic markers. However, the later has been systematically neglected. Whenever possible to collect DNA from the suspect ?problem? animals at the ?crime scene,? it is possible to confrm whether the guilty one has been culled, based on molecular markers, which can avoid overkill. In sustainable use programs, genetic markers can determine the origin of the skin, meat, eggs, and hatchlings, avoiding illegal extraction from wild populations. Finally, in the future eDNA might be used to identify individuals, thus providing information about crocodilian populations. Future studies should prioritize the identifcation of adaptive genes to human-modifed environments and to human management itself to mitigate the anthropic pressures crocodilians face in the Anthropocene, including an unintended domestication process, in which they might become dependent on humans to survive.