Ecology and Natural History
The Broad-snouted caiman is a medium-sized crocodilian. Although its maximum reported size is 3.5 m, animals longer than 2.0 m are presently rare in the wild. This species’ geographic distribution includes the drainages of the Paraná, Paraguay, Uruguay and São Francisco River systems, spreading over regions of northeast Argentina, southeast Bolivia, Paraguay, and northern Uruguay. It also includes a large number of small Atlantic coast drainages from Natal, at the eastern tip of Brazil, to northeast Uruguay. Although this species is eventually sympatric with C. yacare, Medem (1983) reported that C. latirostris was generally found in more densely vegetated, quieter waters. In Paraguay, Scott et al. (1990) found C. latirostris to be a habitat generalist, but when in sympatry with C. yacare it tended to be found in more ephemeral habitat, and was a better colonizer of isolated cattle stock ponds. This kind of man-made habitat has been also reported to be colonized by the species in Brazil (Verdade and Lavorenti 1990) and Argentina (Venturino 1994). Urbanization is also a threat, especially in eastern Brazil, but the species can still be found in urban lakes of the southern region of Rio de Janeiro City (Freitas-Filho 2007). Caiman latirostris has also been found in the mangroves of coastal islands of southeast Brazil (Moulton 1993). According to Yanosky (1994), the Broad-snouted caiman can be found from sea level up to 800 m altitude.
Caiman latirostris is a mound nester, laying 18-50 eggs during the wet season, with a maximum of 129 eggs in a nest from a multiple-laying (Larriera 2002). As its common name implies, it has proportionally the broadest snout of any crocodilian. It has a generalized diet, with the most important food items being snails, shrimp, fish and birds (Diefenbach 1979; Melo1995; Borteiro 2005; Freitas-Filho 2007). Passive feeding behavior has been described (Piña and Larriera 2003), but as a single individual and not cooperative feeding like that described for Alligator mississippiensis (F. Wayne King, pers. comm.) and C. yacare (Schaller and Crawshaw 1982).
Recently, Verdade and Piña (2006) have prepared the Caiman latirostris account for the Catalogue of American Amphibians and Reptiles, which includes details of most of the research on the species.
Text by Verdade et al, 2010
Picture by Edmar Moreira