Chapter 16

Gators and Crocs

Crocodilia

Descendants of the dinosaurs, the large, semiaquatic reptiles in the ancient order Crocodilia appeared 250 million years ago. Alligators, crocodiles, caimans, and Indian gharials all belong to this order. The alligator and crocodile have bodies that are armored with bony plates called osteoderms or scutes.

The Alligatoridae family has only two living members — the American alligator and the smaller Chinese alligator. The American alligator is related to the caimans found in Central and South America. Alligators are considered less dangerous to humans than crocodiles.

The 14 species of “true” crocodiles, or Crocodylidae, are found in tropical areas in Africa, Asia, Australia, and North and South America. The larger species are very dangerous, killing hundreds of people in Asia and Africa each year. The American crocodile is found in the United States only in southern Florida and Puerto Rico.

American Alligator (Alligator mississippiensis)

When European explorers first encountered the American alligator, they confused it with the very real and legendary Old World Nile crocodile. The name alligator came from the Spanish el lagarto, or “the lizard,” which became alagarto in Florida. Soon gaining the nickname gator, they were hunted into near extinction in the 1950s and ’60s. With protection, the population has now very successfully recovered.

Photo of American Alligator sunning itself on a muddy bank.

Most active when the temperature is between 82 and 92°F, alligators will bask or seek warmer water to keep themselves warm.

Description

The osteoderms or scutes on the alligator are olive-brown or black with an off-white underside. Young alligators have yellow stripes on their tails. The snout is broader than that of the crocodile, and the large fourth tooth in the lower jaw is not visible when the mouth is closed, unlike the crocodile. Although an alligator is mature when it reaches 6 to 7 feet in length, females will grow to 9 to 10 feet long and males to 13 to 14 feet long, weighing 800 pounds. Larger animals are frequently seen. Females take 10 to 15 years to mature, and males 8 to 12 years. Life span is uncertain but ranges from 35 to 50 years in the wild and as long as 80 years in captivity.

Alligators swim, propelled by their long, strong tail, at speeds as high as 10 mph. They can dive for long periods. On land they either crawl or sprawl and can rise up on their legs for a high walk, with speeds of 7 to 9 mph for short distances. Alligators will crawl to new bodies of water if necessary. They can stand and step forward in a lunge. They are also strong climbers.

Alligators have a wide range of vision and are excellent at seeing and sensing movement. They also have a good sense of smell. Their jaws are extremely powerful in biting and gripping but comparatively weak in opening against restraint.

Illustration of American Alligator. Adult 6-14 feet.

▲ American Alligator

Map of North America highlighting the American Alligator range.

Native to the southeastern United States, alligators are currently found in all of Florida and Louisiana; southern areas of Alabama, Georgia, and Mississippi; eastern Texas; coastal areas of North and South Carolina; and up into the southeast corner of Oklahoma and southern areas of Arkansas. Over 1 million alligators live in both Florida and Louisiana, their most important range.

Habitat and Behavior

Alligators live in fresh or brackish water, including ponds, lakes, rivers, wetlands, and manmade canals. They dig holes in wetlands, which provide habitat and water for fish and wildlife in dry conditions.

Alligators stop feeding when the temperature drops below 70°F and become dormant below 55°F. During this time, they retreat to dens or long tunnels near open water, keeping their nostrils just above water to breathe, even if their upper body becomes frozen in ice.

Male alligators are solitary and territorial. Large females will also defend their territory and offspring, while young alligators usually share areas. Alligators begin to mate in April through May or June, with the female eventually building a nest and laying 32 to 46 eggs. Hatching is dependent on incubation temperature, but usually occurs in late August or early September. Meanwhile the mother protects her nest, hissing and charging at threats, and she will continue to watch over her young hatchlings for a year or more.

Alligators hunt primarily at night, submerged in water waiting for prey. They consume smaller food in one bite and will attempt to tear off pieces of larger prey by violently spinning or shaking it. Large prey is also cached underwater until it partially rots and can be more easily eaten. Young alligators eat crustaceans, fish, snails, worms, and similar small animals. Older alligators consume larger fish, turtles, snakes, birds, and both small and large mammals such as deer.

Alligators are a very important predator of the very destructive nutria and muskrat. Mature alligators are able to capture very large predators such as bears and Florida panthers. Young alligators themselves are prey for birds, snakes, fish, small predators such as raccoons, otters, and larger alligators. Mature alligators are apex predators that are threatened only by each other in fights or by human hunting.

Human Interactions

Attacks on people and pets are increasing as humans move into alligator habitat, especially next to water. Any poultry, waterfowl, or livestock that is allowed to freely roam in alligator areas is very vulnerable.

Legal status

Federal protection is due to the similarity of appearance with endangered American crocodile. Licenses or permits are required to trap or kill alligators. Contact state alligator nuisance control programs or wildlife agencies for removal.

Feeding alligators is often illegal because it greatly increases the danger to humans.

Crocodile (Crocodylus acutus)

Found more commonly in the Caribbean, Central America, and South America, American crocodiles living in southern Florida are at the extreme northern part of their range. Since the American crocodile’s listing as a federally Endangered species in 1975, the population has increased from a few hundred to about 2,000.

Photo of American Crocodile, taken from the side, showing head and body just past front arm. Croc is sunning itself on a muddy bank alongside a body of water.

The crocodile’s distinctive features include a large, lower tooth that extends out of the mouth and over the upper jaw, as well as a narrow, V-shaped head and snout.

Description

American crocodiles have osteoderms or scutes on their back and a long, strong tail. Lighter colored than alligators, crocodiles are grayish green with yellowish-white undersides. Young crocodiles are lighter tan with dark stripes. They are distinguished from alligators by their narrow head and tapered snout, and the fourth lower tooth that is exposed when the mouth is shut. The ears, eyes, and nostrils are located on the top of the head, so that they are exposed while the rest of the crocodile is submerged. The front legs have 5 toes on each foot and the rears have 4 toes. Mature males can reach 14 to 15 feet long with weights of 800 pounds or more, while females are generally 8 to 12 feet long. Average life expectancy is 60 to 70 years, although some individuals reach 100 years or so.

Illustration of American Crocodile profile. 19-22 inches at shoulder. 24-42 inches from tip of nose to rump. Tail 5.5-10 inches.

▲ American Crocodile

Map of North America highlighting the American Crocodile range. Crocodiles are found only in tropical southeast Florida and coastal Pacific Mexico.

In the United States, crocodiles are found only in tropical southeast Florida.

Habitat and Behavior

Coastal brackish and saltwater estuaries, swamps, creeks, and ponds are their primary habitat, but crocodiles have recently moved through freshwater canals into other areas. Shy and reclusive in nature, crocodiles construct burrows for resting and protection in cold weather. Provided with sufficient food, crocodiles are solitary and do not leave their own area except during mating season. In late April and early May, females build their soil nests above water, lay 20 to 60 eggs, and return near hatching time in late July or early August. After assisting the hatchlings for a day or so, the female leaves the area.

Crocodiles bask in the sun and are sometimes seen with their mouths open. This gaping behavior is related to regulating their body temperature and is not aggressive. During dry seasons, crocodiles will bury themselves in mud and become lethargic. Crocodiles will submerge themselves in water during cooler weather but are unable to survive in temperatures below 45°F.

Primarily feeding at night, young crocodiles eat crustaceans, small fish, and amphibians; while larger adult crocodiles feed primarily on large fish, and less commonly on turtles, snakes, birds, small mammals, and the occasional deer. At any time, crocodiles may lurk below the surface waiting for animals that approach the water’s edge. Although large fish, raccoons, and larger predators frequently prey on juvenile crocodiles, adult crocodiles are apex predators.

Human Interaction

Conflicts between crocodiles and humans are rare, partially due to their low numbers. The first human attack in Florida occurred in 2014. Crocodiles will take dogs, goats, pigs, or cattle if available. Crocodiles can be more aggressive toward humans than alligators are.

Legalities

Crocodiles are a federally protected Endangered species.

Alligator or Crocodile Encounters

Pay close attention for the presence of alligators or crocodiles when you are near water at dusk, dawn, or during the night and in the warmer months. Alligators living in waterways or ponds near housing or golf courses can become dangerously habituated to humans, even during daylight.

Attacks occur most often when a person is attempting to pick up or capture an alligator, followed by swimming, fishing, and retrieving golf balls. An average of 5 human attacks occur yearly, with at least 19 deaths since 2000. Dogs and other small animals are attacked far more than humans. Seek treatment for any bite to prevent infection from the large amounts of bacteria in an alligator’s or crocodile’s mouth.

Recreation

Practice safety measures when hiking, kayaking, fishing, hunting, or camping. Inquire about current alligator or crocodile activity before recreation in known habitats.

Camping

Fishing

If you encounter an alligator or crocodile, or it is attracted to your lure, stop and move away. Do not release fish where alligators or crocodiles are present, to prevent association with humans. Dispose of fish scraps or waste appropriately.

Hunting

Do not clean game meat or discard entrails in or near water or near your campsite.

Kayaking

Be extremely cautious of shallow, narrow areas 5 to 10 feet wide. Do not cut around bends too closely or enter shallow areas where alligators like to hide and wait for prey. If an alligator or crocodile is observed, try to keep a distance of 100 feet. Use great caution when entering and leaving the water.

Caimans (Caiman crocodilus)

Spectacled caimans, probably former pets, were first found in southern Florida in 1960. They are primarily found in freshwater lakes and canals. Looking more like crocodiles, caimans are olive brown, with more pointed snouts than alligators. Invasive caimans have not exceeded 6 feet in length. Caimans are able to reproduce in the very southern areas of Florida and do not survive winters north of central Florida. Caimans are aggressive if confronted or threatened.

Caiman breeding populations are now found in Broward and Dade counties, with individuals sighted elsewhere.

Dealing with Alligators and Crocodiles

The following advice refers to alligators. Although quite rare, crocodiles behave very similarly and the same precautions are necessary in their areas.

Homes and Yards

Alligator Attacks

Damage ID: American Alligator and American Crocodile

Prey On

Poultry, pets, goats, pigs, cattle

Time of Day

Primarily night

Method of Kill

Tracks

Front, 5 long toes with one facing to the rear. Rear, 4 long toes and long heel pad. Claw marks visible. Walking tracks may show the drag of the tail and the prints of all four feet; or the tail may obscure the footprints.

Illustration of alligator tracks — front, rear, and tail.

Alligator

Illustration of crocodile tracks — front, rear, and tail.

Crocodile

Gait

On land, either crawl or rise on hind legs to walk short distances. Crawl is an alternate diagonal pattern, with front left and rear right moving together. Crawl may be slow with stomach and tail also on ground. At faster speeds body lifts off ground and tail moves quickly from side to side.

Scat

White in color, scat primarily consists of undigested calcium from bones and shells.

Illustration of Alligator scat.
Illustration of Crocodile scat.