Broad-snouted caiman (Caiman latirostris)

Also known as: broad-nosed caiman
KingdomAnimalia
PhylumChordata
ClassReptilia
OrderCrocodylia
FamilyAlligatoridae
GenusCaiman (1)
SizeLength: up to 3.5 m (2)

The broad-snouted caiman is classified as Least Concern (LC) on the IUCN Red List (1) and is listed on Appendix I of CITES, except for the Argentine population which is listed on Appendix II (3).

The broad-snouted caiman (Caiman latirostris) is, as its common name implies, recognised by its exceptionally broad snout that is nearly as wide at the eyes as it is long . A medium-sized crocodilian, the broad-snouted caiman grows up to 3.5 metres in length, but normally measures around 2 metres. The upperparts are heavily covered in horny scales, plates and ridges, with a distinctive fold that runs down the snout (2) (4). 

Adult broad-snouted caimans tend to be pale olive green with uniformly light underparts, although older animals are nearly black. Juveniles are brownish olive, with dark stripes on the back and dark blotches on the head and sides of the lower jaw (2) (4).

Found only in south-eastern South America, the broad-snouted caiman occurs in north Argentina, Bolivia, southeast Brazil, Paraguay and Uruguay (1) (2). 

Its range extends along the southeast coast of Brazil, from Rio Grande do Norte and Lago dos Pato, southwards to Lago Merim, and westwards to Mato Grosso and the upper Rio Paraguay in Brazil, as well as eastern Bolivia, the lower Pilcomayo in Paraguay, northern Argentina, and the coastal wetlands of Uruguay (5). 

A highly aquatic species rarely found far from water, the broad-snouted caiman primarily inhabits mangroves, marshes and swamps of fresh, brackish and salty water. It is also found in mangroves surrounding small coastal islands in southeast Brazil (2) (5). 

Where the Yacare caiman (Caiman yacare) is found, the broad-snouted caiman prefers slow-moving waters in dense forest, although it occupies a greater variety of habitats where this species is absent. The broad-snouted caiman is also capable of occupying man-made habitats, such as cattle stock ponds. It is known to occur up to elevations of around 600 metres (2).

Due to a lack of field studies, very little is known about the behaviour and ecology of the broad-snouted caiman, and much of what is known about its reproduction has come from captive individuals in zoos (6). 

The broad-snouted caiman nests during the rainy season (August to January in Brazil, January in Uruguay, and January to March in Argentina), when decaying vegetation is collected from around a nest site and scraped into a mound (2) (5). The male assists with constructing the mound nest, but the female becomes more aggressive as incubation continues, and only the female tends the nest (5). Around 20 to 50 eggs, or as many as 90 in some locations, are laid in two layers in the nest, with the layers separated by vegetation (5). This layering of the eggs may help to create a slight difference in temperature within the nest and a slightly different sex ratio in the embryos (7), since only females are produced between 29 and 31 degrees Celsius, only males are produced at 33 degrees Celsius, and both males and females are produced at 34.5 degrees Celsius (8). After an incubation period of around 63 to 70 days, the female breaks open the nest and carries the hatchlings in her mouth to the water. For their first year, the hatchlings cluster in the water close to the nest, all the time being closely attended by both the adults as protection from predators (5). 

The broad-snouted caiman has a varied diet that includes shrimp, fish and birds (7), but in some parts of its range it feeds mainly on snails (6). To maintain its body temperature, it basks for about 30 minutes on summer mornings and for up to 4 hours in spring and autumn, often with an additional period in the late afternoon. It is only active on sunny days during the winter. The broad-snouted caiman can apparently survive colder temperatures than other crocodilians in the region, and its dark colour may be an adaptation to this, as darker colours are better at absorbing light which is converted to heat (5).

The greatest threat to the broad-snouted caiman was once illegal hunting for its hide, and this exploitation was particularly destructive during the middle of the 20th century (2). Illegal hunting still persists in some areas, such as in north-eastern Brazil, where the broad-snouted caiman supplies meat for local markets in small cities along the São Francisco River basin. However, it is not considered a major threat to the species anymore (7). This is mainly because the broad-snouted caiman is now harder to find, making hunting less attractive and more costly when traders can obtain better quality legal skins. Populations in Bolivia, however, are severely depleted, most likely as a result of continued hunting (2). 

Habitat degradation is now considered the greatest threat to the broad-snouted caiman. Deforestation pressures from hydroelectric projects are very severe in Brazil and Uruguay, and most of the natural wetlands of the Paraná and São Francisco River systems in Brazil have been dammed for large hydroelectric stations. Vast wetland areas have also been drained for agricultural purposes, while pollution is a considerable problem in rivers that flow through large cities in Brazil (2) (7).

Legal protection is in place for the broad-snouted caiman in most range countries, although this is often difficult to enforce. Some depleted populations have been restocked and sustainable harvesting of this species has been implemented in some areas (2). This has proved most successful in Argentina, where ranching programmes have discouraged illegal hunting by rewarding local people for finding caiman nests, a set number of which are then taken so that the hatchlings can be harvested for their hides (7). This management of wild populations was promoted in 1997 when CITES downgraded the listing of the Argentine population to Appendix II, allowing limited, carefully monitored trade in broad-snouted caiman products (3).

To find out about conservation projects where the broad-snouted caiman is found, see:

This information is awaiting authentication by a species expert, and will be updated as soon as possible. If you are able to help please contact:
arkive@wildscreen.org.uk

  1. IUCN Red List (January, 2011)
    http://www.iucnredlist.org/
  2. Crocodilian.com – Broad-snouted caiman (January, 2011)
    http://www.flmnh.ufl.edu/cnhc/csp_clat.htm
  3. CITES (January, 2011)
    http://www.cites.org/
  4. World Association of Zoos and Aquariums – Broad-snouted caiman (January, 2011)
    http://www.waza.org/en/zoo/choose-a-species/reptiles/crocodiles/caiman-latirostris
  5. Groombridge, B. and Wright, L. (1982) The IUCN Amphibia-Reptilia Red Data Book. IUCN, Gland, Switzerland and Cambridge, UK.
  6. Thorbjarnarson, J. (1992) Crocodiles: An Action Plan for their Conservation. IUCN, Gland, Switzerland.
  7. Verdade, L.M., Larriera, A. and Piña, C.I. (2010) Broad-snouted caiman Caiman latirostris. In: Manolis, S.C. and Stevenson, C. (Eds) Crocodiles. Status Survey and Conservation Action Plan. Third Edition. Crocodile Specialist Group, Darwin.
  8. Piña, C.I., Larriera, A. and Cabrera, M.R. (2003) Effect of incubation temperature on incubation period, sex ratio, hatching success, and survivorship in Caiman latirostris (Crocodylia, Alligatoridae). Journal of Herpetology, 37(1): 199-202.