By Kate Perez (Own work) [CC BY-SA 4.0 (http://creativecommons.org/licenses/by-sa/4.0)], via Wikimedia Commons
By Kate Perez (Own work) [CC BY-SA 4.0 (http://creativecommons.org/licenses/by-sa/4.0)], via Wikimedia Commons

Alligator mississippiensis
Order: Crocodylia

Husbandry Information

Housing Requirements

  • Need a tank at least twice the length of the animal.
  • Enclosure should have a place where the alligator can haul out to bask. If housed indoors you need to provide UV lighting.
  • If housing baby alligators outdoors a cover is needed to protect them from predators.
  • Enclosure is ideally 1/3 land (with the animal having the ability to get completely out of the water for basking) and 2/3 water (water should be deep enough for animal to completely submerge its body and swim).

Diet Requirements

  • In the wild, adults eat fish, turtles, snakes, mammals, and birds. They will also take carrion if it is available and they are hungry enough. Juveniles eat a wide variety of small invertebrates, mostly insects, small fish, and frogs.
  • Feeding activity is governed by water temperature. Foraging will cease if the temperature drops below 68 to 73 degrees. They can easily last the winter on their energy reserves.
  • As predators at the top of the food chain, they help control the population of rodents and other animals that might overtax the marshland vegetation.
  • In captivity, they are fed carp, rats, and chicken.
  • Commercial crocodilian chow is available. The small pellets work well for babies and small juveniles. The larger biscuits work for alligators over 3 feet long.

Veterinary Concerns

  • Alligators are susceptible to West Nile Virus.

Notes on Enrichment & Training

  • Running or spraying water is an easy enrichment.
  • A few alligators can be trained to walk on a leash. It requires an animal with a calm, relaxed demeanor. This training should not begin until the alligator is about three feet long.


Programmatic Information

Tips on Presentation

  • As alligators grow older, they will become increasingly difficult to restrain, handle, and present. Have a disposition plan in place before adding this species to an ambassador collection.

Tips on Handling

  • It works best to get very young alligators and begin handling for short periods of time.
  • Rocking or gently bouncing the alligator will calm it down. This method even works on larger alligators.
  • When picking up a gator from the water it is best to grasp the animal gently from the top, then rotate the hands under the chest and pelvis before lifting it out of the water. This makes the animal less likely to struggle when picking it up.

Potential Messaging

  • A success story! Through habitat protection, commercial captive breeding and other conservation efforts the American alligator was removed from the Endangered Species list.
  • Can talk about danger of releasing non-native animals - Burmese pythons in the Everglades are displacing the alligator as apex predators.
  • In general, animals seen at the zoo do not make good pets. Most have specialized dietary, veterinary, housing, and social needs that are difficult or impossible for even dedicated pet owners to meet. Always ensure that your future pet has not been taken from the wild. Capture of wild animals for the pet trade has significantly damaged the survival prospects of species such as sloths, tamanduas, and many parrots. Captured animals are typically mistreated by profit-motivated traffickers and dealers, resulting in many animal deaths; well-meaning animal lovers may feel like they are rescuing animals by purchasing them but are really perpetuating the cruelty. In addition, many exotic pets are released by their owners when they become too dangerous or demanding, often with devastating effects on local ecosystems. Animals that should never be kept as pets include all bats, primates, and exotic carnivores. Birds, fish, and reptiles have specialized needs, are frequently wild-caught, and damage the local environment if released; guests should be advised to educate themselves and proceed with caution. Domestic dogs and cats are almost always the best option! Many deserving animals are available for adoption at animal shelters. http://www.philadelphiazoo.org/Save-Wildlife/Images/PetWalletBro2012.aspx http://pin.primate.wisc.edu/aboutp/pets/index.html
  • On the Ambassador Animal Advisory one individual state that they are great ambassadors for education programs that include native wildlife, adaptations for semi-aquatic environment and body coverings.

Acquisition Information


Many alligators that come to zoos are rescued illegal pets. These animals may be fearful or aggressive, but sometimes can be handled if you have the time to invest.

Comments from the Rating System

  • Binghamton Zoo at Ross Park: Can be difficult to restrain depending on size.
  • BREC's Baton Rouge Zoo: Small alligators are easy for almost any handler, but once over about 3 feet long, they require an experienced handler, especially during summer when they are most active. Only rare individuals can be safely handled over 6 feet long. "Rescue" alligators often have behavioral issues.
  • Maryland Zoo in Baltimore: Good temperaments, but they grow quickly.
  • Natural Science Center at Greensboro: Juveniles only.
  • Zoo Atlanta: Size considerations.


Natural History Information

Range and Habitat

American alligators are found in the southeastern United States: Alabama, Arkansas, North Carolina, South Carolina, Florida, Georgia, Louisiana, Mississippi, Oklahoma, and Texas. They're found in swamps, ponds, lakes, sluggish rivers, and marshes. They can tolerate a reasonable degree of salinity for short periods, and are occasionally found in brackish water around mangrove swamps. That said, they lack the buccal salt-secreting glands present in crocodiles.

Physical Description

The American alligator is generally olive-brown to black in color. Juveniles are essentially miniature versions of the adults, but they have bright yellow cross-bands on a black backgrounds (disruptive coloration.) They have a broad, flat head with a rounded snout. The bottom teeth are not visible when the mouth is closed. Their short, sturdy limbs end in webbed feet with sharp claws.
Adult males typically reach lengths of 13 to 14.5 feet, and females can get to just under 10 feet long.

Life Cycle

Females reach sexual maturity when they are about 6 feet long. Males and females engage in a courtship ritual before breeding. It involves low-frequency bellowing, which travels great distances in water, advertising an individual's presence. There is also head-slapping on the water surface, transmitting visual and aural messages. Complex body postures communicate additional information, which is reinforced with odor from paired musk glands everted from under the chin and from the cloaca. Near the end of the courtship, both animals will engage in a bout of snout and back rubbing. Overall, this courtship can last for several hours, and is thought to help synchronize both spermatogenesis (sperm production) and ovulation (release of eggs from the ovaries.)
After breeding, the female will build a nest of vegetation, sticks, leaves, and mud in a sheltered spot in or near the water. She will lay 20 to 50 white, goose-egg-sized eggs, and then cover them with more vegetation. The vegetation, like mulch, heats as it decays, helping to keep the eggs warm. The temperature at which alligator eggs develop determines the sex of the hatchlings. Males develop in temperatures ranging from 90 to 93 degrees Fahrenheit, and females develop in temperatures from 82 to 86 degrees Fahrenheit. Intermediate temperatures will yield a mix of both males and females. The eggs will develop for 65 days, and the female will remain near the nest to protect it from predators.
When the young begin to hatch, they emit a high-pitched croaking noise, and the female hears this and starts to dig her young out of the nest. She will stay with her young for their fist 1 to 3 years.
American alligators can live on average to 50 years. The record is 65 years, but that death was accidental. They may be able to live for as long as 100 years.

Behavior

Alligators spend much of their day basking of shores of rivers and lakes, hidden in vegetation. The tail, which accounts for half of the alligator's total length, is primarily used for aquatic propulsion. The tail can also be used as a weapon of defense when an alligator feels threatened.
While alligators travel very quickly in water, they are generally slow-moving on land. That said, they do have the ability to sprint at speeds of up to 30 miles per hour for short distances. Alligators are capable of killing humans, but they generally fear humans enough to avoid them as prey. They are far less dangerous than the infamous Nile crocodile and saltwater crocodile. Alligator bites are serious injuries due to the risk of infection.

Threats and Conservation Status

Historically, alligators were depleted from many parts of their range as a result of market hunting and loss of habitat, and 30 years ago many people believed this unique reptile would never recover. In 1967, the alligator was listed as an endangered species (under a law that preceded the Endangered Species Act of 1973), meaning it was considered in danger of extinction throughout all or a significant portion of its range. A combined effort by the U.S. Fish and Wildlife Service, state wildlife agencies in the South, and the creation of large, commercial alligator farms saved these unique animals. The Endangered Species Act prohibited alligator hunting, allowing the species to rebound in numbers in many areas where it had been depleted. As the alligator began to make a comeback, states established alligator population monitoring programs and used this information to ensure alligator numbers continued to increase. In 1987, the Fish and Wildlife Service pronounced the American alligator fully recovered and consequently removed the animal from the list of endangered species. The Fish and Wildlife Service still regulates the legal trade in alligator skins and products made from them. Although the American alligator is secure, some related species - such as several different species of crocodiles and caimans - are still in trouble.


Did you know…

  • Alligators' broad, heavy heads are adaptations to living in heavily vegetated swamps. A heavy head has more momentum to help catch prey by smashing through thick vegetation.
  • When ponds and swamps inhabited by the American alligator freeze over, the larger alligators survive by lying in shallow water and breathing through a hole in the ice. This is called the "icing response." Occasionally, alligators may be trapped completely below the ice, and have been known to survive for over 8 hours without taking a break, because the freezing water slows their metabolic rat down to very low levels.
  • Alligator is derived from the Spanish el lagarto which means "the lizard." Mississippiensis means "of the Mississippi (River)," derived from mississippi + ensis (Latin for "belonging to.")


Photographs




Contributors and Citations

  • The Philadelphia Zoo
  • Notes from comments gathered from completed PARIS rating sheets
  • Baton Rouge Zoo