Species Fact Profile: Orinoco Crocodile (Crocodylus intermedius)

                                                                  Orinoco Crocodile

Crocodylus intermedius (Graves, 1819)

Range: Orinoco and Meta River Basins of Venezuela and eastern Colombia

Habitat: Llanos (Flooded Savannah), Freshwater Rivers

Diet: Juveniles feed on crabs, snails, and other invertebrates while larger individuals take fish and birds; large adults may take prey up to the size of capybara

Social Grouping: Largely solitary, but will congregate around water during dry season.

Reproduction:  Males attract females by roaring.  Females dig nest holes in the sides of sand banks during the dry season.  Up to 70 eggs laid in the nest, hatching 2.5-3 months later at the start of the wet season.  The sex of the hatchlings is determined by incubation temperature.  Females will guard the nest and may remain with the hatchlings until they are as old as three years.  Sexual maturity is determined by body length: 2.5 meters for females, 3 meters for males 

Lifespan: 70-80 Years

Conservation Status: IUCN  Critically Endangered.  CITES Appendix I. 

• Possibly the largest crocodilian species in the New World (and therefore the largest predator in the Americas) – unconfirmed lengths of up to 6.6  meters from 1800, though 3-5 meters is far more typical for a large male.  It is believed that the genes for large size were culled from the population during the skin-trade days, when larger individuals were the most sought after by hunters.  Males typically weigh 380 kilograms, females 200 kilograms
• Adults are light yellow-green on the dorsal surface, fading into yellow and then white on the underside, with gray or black banks on the back and tail.  Juveniles similar to adults but with more blotching and spotting.  Melanistic individuals have been reported but not confirmed.  An individual’s skin can change color over long periods of time 
• Head and snout are relatively slender and elongated (the species name intermedius refers to snout being intermediate between that of the gharial and other very slender-snouted crocodilians and those of other species)
• Occasionally reported to prey on domestic animals.  Unsubstantiated reports of predation on humans (Alexander von Humboldt was told by natives in the region in 1800 that 2-3 adults of the tribe were killed by crocodiles per year).  Attacks on humans reported as recently as 2009 and 2011, though neither ended in fatality
• Hatchlings and juveniles may be preyed upon by tegus, anacondas, coati, caiman, vultures, and jaguars; humans – and possibly jaguars – are the only likely predators of adults
• Occasionally sightings  sightings are reported from Trinidad and other island in the Caribbean, though these may be vagrants forced out to sea, or may be misidentified American crocodiles
• Population greatly reduced by massive over-exploitation for skins in the mid-1900s, reducing the population to as few as 100.  Considered especially desirable for their large size and very smooth belly skins, relatively free of bony plates.  Relatively easy to hunt in the dry season, when they congregate in large numbers around relatively small bodies of water.  Teeth are believed to have medicinal value in local cultures.
• Current threats include hunting for meat and eggs and entanglement and drowning in fishing nets.  Habitat being lost due to agriculture (ranching) and aquaculture.  Also facing competition from dense populations of caimans, which have moved into their former habitats
• In Venezuela, a captive-breeding and reintroduction program is underway, with releases at a variety of sites.  Similar programs being considered for Colombia

      

      Zookeeper's Journal: I saw my first Orinoco crocodile in 2008 at the Dallas World Aquarium.  That shouldn’t be surprising – back then, I feel like almost anyone outside of South America saw their first Orinoco crocodile at DWA.  There really weren’t many other places where they could be seen.  DWA obtained their first pair from the Venezuelan government in 1998 after signing a conservation agreement (I can’t help but think that such a partnership would not be possible today, given our relations with Venezuela).  The crocs were some of the stars of Dallas’ “Orinoco – Secrets of the River” rainforest exhibit, which is where I first encountered them.  The pair, male Juancho and female Miranda, bred successfully for the first time in 2003, the first of their species to be born in the United States.  When I visited for the second time in 2008, this time as part of a behind-the-scenes tour with other visiting reptile keepers, there was an entire back room at the Aquarium almost overflowing with hatchling and juvenile Orinocos, one of which I was able to handle.  Many of those crocodilians would later be repatriated to Venezuela, some for reintroduction into the wild.  Others found their way into other AZA facilities, and today the Orinoco crocodile is no longer an especially unusual sight in zoos.  That being said, I wonder how sustainable this program will be, what with almost all of the crocodiles coming from the pairing of Juancho and Miranda.  I don’t consider it particularly likely that the Venezuelans will be in a hurry to send new crocodiles for fresh genetic material, and I wonder if perhaps it would have been prudent to try to get some additional crocs out of South America while it was still possible.  If nothing else, it’s been clearly demonstrated that this species can thrive under human care and produce plentiful offspring, which can then be reintroduced back into the wild.  What remains to be seen is if the resources and determination are still in place down in the range countries to make the saving of this species possible.