Image (c) P. Ross, crocodilian.com
Order: Crocodylia
Family: Crocodylidae
Subfamily: Crocodylinae
Genus & Species: Crocodylus moreletii
APPEARANCE
Morelet's crocodile is a small, poorly understood species of Central American crocodile. Sexual dimorphism may be present in this species, with males being larger than females. They attain lengths of 10-14 ft (2.2-4.7 m). They are similar in appearance to the American crocodile — in fact, until the 1920's is was confused with both the American and Cuban Crocodiles. The main distinction is its unusually broad snout. The nostrils are situated at the end of the snout, behind the snout are the eyes, and behind the eyes are the ears. These three sensory receptors are all located on the same plane on the top of the head, allowing it to stay almost completely submerged underwater while still being able to see, hear, and smell. The eyes have a special eyelid called a nictitating membrane, which is a clear eyelid that covers and protects the eye while underwater. The eye's iris is silvery-brown in colour.
Morelet's crocodiles have 66-68 teeth. The teeth in the upper and lower jaws are in perfect alignment, which distinguishes all crocodiles from alligators. The fourth tooth on either side of the bottom jaw is slightly larger than the other teeth and is visible when the mouth is closed.
Morelet's crocodiles are similar in colour to the American crocodile, but are somewhat darker. They are a dark greyish-brown in colour, with even darker bands and spots on the body and tail. The body lacks ventral osteoderms (bony plates beneath the skin) and is highly valuable for tanning. The legs are powerful and end in clawed, webbed feet. The tail is also very powerful, and allows Morelet's crocodiles to swim with its powerful thrusts.
Juveniles are bright yellow in colour with black bands.
HABITAT
Morelet's crocodiles are found in northern and central coastal Belize, as well as areas in Mexico and Guatemala. Captive Morelet's crocodiles have also escaped from farms to form feral populations in Mexico outside of their regular breeding area. They seem to prefer freshwater, and are found mainly in swamps, marshes, rivers, and lakes in forested areas. They will also live in brackish waters (areas where salt and freshwater meet). They can also be found in lowland rivers and ponds.
Their range overlaps that of the American crocodile.
FOOD
Morelet's crocodiles vary in appetite according to age and size. Juveniles eat small invertebrates and fish. Adolescents feed on aquatic snails, fish, small birds, and mammals. Older and larger crocodiles feed on larger prey, including domestic animals such as dogs, as well birds, fish, lizards, and Kinosternon mud turtles. They can also be cannibalistic, eating young juveniles. Morelet's crocodiles are generally shy around humans, but 14 ft (4.7 m) specimens may attack.
ENEMIES
During the 1940's and 1950's, Morelet's crocodiles were hunted almost to extinction due to their valuable hide. When the Wildlife Protection Act was passed, there were very few left in the wild. Since hunting them became illegal, their numbers began to steadily rise. However, due to illegal poaching and habitat loss, their numbers are again dropping. To counter this, they are being raised on crocodile farms in Mexico, where some have escaped to form feral populations. This has caused problems for the endangered American crocodile, which now must compete with them for food in these areas.
Studies are being done to find the effects of endocrine disrupting compounds (EDC's) on populations of Morelet's crocodiles in Belize. It is thought that these compounds may affect the eggs in some way.
BREEDING
Morelet's crocodiles have the distinction of being the only North American crocodile to build mound nests only, and not mound and hole nests. The breeding season starts before the rainy season. 20-45 eggs are laid in a mound nest near the water or on floating vegetation. Nests may contain eggs from more than one female. Females guard the nest for 80 days, after which the eggs hatch. Both parents protect the juveniles from enemies.
RELATIVES
There are no subspecies of Morelet's crocodiles.
RESOURCES CITED
1. www.flmnh.ufl.edu/natsci/herpetology/brittoncrocs/csp_cmor.htm
2. www.belizezoo.org/zoo/zoo/herps/cro/cro1.html
3. www.flmnh.ufl.edu/natsci/herpetology/brittoncrocs/!cmor4.htm
4. www.flmnh.ufl.edu/natsci/herpetology/act-plan/cmore.htm
5. es.epa.gov/ncerqa_abstracts/grants/97/endocrine/mcmurry.html