The Broad-snouted Caiman (Caiman latirostris): A Model Species for Environmental Pesticide Contamination Assessment

ODETTI, LUCÍA M.; SIMONIELLO, MA. FERNANDA; PABLO A. SIROSKI; G. L. POLETTA

Bird and Reptile Species in Environmental Risk Assessment Strategies

Royal Society of Chemistry

Año: 2023; p. 196 - 209

University of HelReptiles are relevant models in evolutionary history and have great ecological,sociological and commercial importance. They are transcendental innatural ecosystems as prey, predators, herbivores, seed dispersers andbioindicators of environmental health.1Caiman latirostris is a crocodilian species that inhabits the north-centralregion of Argentina and it constitutes a valuable commercial and ecologicalresource in South America. The geographical distribution of this speciesincludes the northeastern part of Argentina, southeastern Bolivia, Paraguay,Brazil and northern Uruguay.2 In particular, in Argentina, C. latirostris isdistributed in Formosa, Santa Fe, Misiones, Corrientes, Entre Rı´os, Chaco,Santiago del Estero, Salta and Jujuy provinces. It is an ectothermic specieswith a well-defined seasonal cycle that depends on climatic factors (externaltemperature and hydrological regime). In Argentina, breeding takes placebetween November and January, with an incubation period of approximately65–75 days at 31 1C. At hatching, the young weigh about 40 g and measureapproximately 22 cm long. The size of adult males is in the order of 2.60 m inlength and about 80 kg in weight Since the year 1990, the wild populations of C. latirostris of the Province of Santa Fe have been managed through a program based on the ‘‘ranching’’technique (harvesting eggs in nature, captive breeding and returning tonature), known as ‘‘Proyecto Yacare´’’, which allowed a significant recovery ofnatural populations of this species.3 From then on, the sustainable commercialuse of C. latirostris through the passing of Provincial Law No. 11.820has become an alternative of maximum interest to the Province of Santa Fewithout any risk for the species conservation. Ranching programs are basedon the critical factor represented by embryonic and perinatal high mortality,characteristic of these species. The implementation of this managementmethodology prevents the loss of eggs produced in nature and the great mortality of individuals under the first year of life, with the reintroductioninto the nature of a number of animals higher than those that would havesurvived naturally. These programs actively involve local people in theidentification and preservation of nesting areas, which has beneficial effectsnot only for the species under management but also for all the taxa thatshare its habitat.3 As a result of the implementation of these programs inArgentina, natural populations of caimans have recovered from an extremelyendangered situation, returning to stability since 1997.