Alligator: Habitat, Diet, Behavior & More (Species Overview)

Alligators are large, intelligent reptiles that are found in warm, slow-flowing, freshwater locations in the United States and China. 

Alligators can become nuisance creatures. They encroach onto people’s properties and pose risks to the health and life of people and their pets. Alligators are also often confused with lizards, crocodiles, and dinosaurs, yet there are key differences.  

This article provides extensive information about the alligator to clear up any misconceptions as well as provide detailed information about the animal’s habitat, characteristics, behaviors, and more.

Alligator

Scientific name: Alligator

There are only two species of alligators in the present-day world.  

These two species are the following:

  • American Alligator (Alligator mississippiensis)
  • Chinese Alligator (Alligator sinensis)

As denoted by their names, American alligators are found in the United States, and Chinese alligators are in China. 

The Chinese alligator may also be referred to as the Yangtze alligator or the muddy dragon.

They both belong to the class of Reptilia and the order Crocodylia (or Crocodilian) which makes them related to reptiles and crocodiles. 

Please note that lizards and alligators are not the same, however. Lizards belong to a different reptilian order called Squamata.

As reptiles, alligators present the following characteristics:

  • Lung respiration
  • Vertebrate (belong to the phylum Chordata, meaning spinal cord)
  • 4-legged
  • Have scales (called scutes)
  • Ectothermic (cold-blooded)
  • Lay eggs
  • Amniote (embryonic or fetal development within a closed sac)

The taxonomic hierarchy of the alligator is as follows:

Hierarchy LevelClassification
KingdomAnimalia
PhylumChordata
ClassReptilia
OrderCrocodylia
FamilyAlligatoridae
GenusAlligator
Speciesmississippiensis (American) or sinensis (Chinese)

Appearance And Size

While the appearance is generally the same between the two species of alligators, overall size can vary.

Appearance

Skin And Scales

Alligators appear primarily in camouflage colors of brown, green, olive, black, or dark gray. Their underbelly is a light creamy color. 

When young, American alligators appear black with yellow banding, changing to camouflage colors as they age. 

Chinese alligators may also appear black with faint yellow markings.

They have dermal-connected, hard, and bony scutes which overlap as protective scales. Their skin is thick ranging from 7 to over 17 inches as it grows. Both the skin and scales will shed and regrow.

Head, Snout, And Mouth

Their eyes and nostrils are located on top of their heads and snouts. This allows alligators to submerge nearly completely while keeping these above the surface of the water.

The snout of an alligator is a broad U-shape with an overbite, which is different from a crocodile. 

Alligators have thecodont teeth, which are teeth enclosed in deep bone sockets. The lower jaw’s teeth are out of sight when the jaw is closed. They can regrow lost teeth up to 50 times in their lifespan, going through up to 3,000 teeth.

Alligators have large, stable, and muscular tongues. They extend the length of the snout, up to 2 feet in length in adult alligators. 

They have a palatal valve that seals their throat, allowing them to prevent water from entering their lungs when opening their mouth underwater.

Tail

Similar to other crocodilians, alligators have powerful tails used for defense, swimming, jumping, and lunging.

Size

On average, an alligator is around 6 feet in length. However, age, gender, and species cause variances.

The American alligator can grow up to 15 feet in length, weighing 1,000 pounds or more.

The Chinese alligator can grow up to 5 to 7 feet in length, weighing up to 85 pounds.

At birth, a hatchling only weighs 1 or 2 ounces. It takes anywhere from 10 to 20 years for an alligator to reach its maximum length, and can grow up to 1 foot per year. 

In times of food scarcity or abundance, an alligator’s weight will fluctuate.

Male vs. Female

Male alligators are bigger than females.  

The average size for a mature female American alligator is 8.2 feet, weighing 200 pounds or more. 

Female Chinese alligators are about three-quarters the length of males, weighing less than 50 pounds.

Largest Alligators

This table shows some of the largest alligators that have been discovered:

WhereWhenSize
Louisiana189019.2 feet; 2,000 pounds
Texas199813.85 feet; 900 pounds
Florida201014.35 feet; 654 pounds
Arkansas201213.3 feet; 1,380 pounds
Mississippi201212.9 feet; 697.5 pounds
Alabama201415.9 feet; 1,011.5 pounds
Florida201615 feet; 800 pounds

Preferred Habitat

Alligators are semi-aquatic, living where land meets freshwaters in warmer areas. 

They can be found in lakes, marshes, swamps, rivers, and even swimming pools. They will burrow in muddy, water-filled banks and bask on land or in trees to thermoregulate.


Primary Foods

Alligators are carnivorous, eating a varied meat-filled diet. This includes fish, snakes, turtles, small mammals, and birds. They may even hunt larger prey such as cattle or deer.  

Young, juvenile alligators eat smaller prey such as insects, amphibians, and invertebrates.

Alligators are also opportunistic feeders, eating carcasses and wounded animals.

This animal has a powerful sense of smell, capable of smelling blood from miles away. In the water, they have integumentary sensory organs that allow them to feel vibrations and movements.


Population Estimates

There are an estimated 5 million American alligators in the United States.

They were on the endangered species list in 1967, but today are classified as the least concern. Louisiana has the highest number of alligators at around 2 million.

The Chinese alligator population is critically endangered, with an estimated population of fewer than 120 animals. 


Range & Distribution

American Alligator

The American alligator is found primarily in 10 of the United States in areas with freshwater sources. 

While alligators can tolerate colder water, they choose to live in places where it does not freeze. Alligators may wander into neighboring states, but typically do not live or breed there.

They can be found in the following 10 states:

  • Louisiana
  • Florida
  • Texas
  • Georgia
  • South Carolina
  • Alabama 
  • Mississippi
  • Arkansas
  • North Carolina
  • Oklahoma

Chinese Alligator

A long time ago the Chinese alligator could be found in the marshlands and lakes in regions of the Yangtze River and along the water in the Hubei Province.

Today, the Chinese alligator is critically endangered, found primarily in eastern China. The alligators live in the lower Yangtze River, in the Anhui and Zhejiang provinces.


Breeding Behaviors

Alligators start to breed once they mature. For both females and males, this is when they have reached an approximate length of 6 feet, typically at the age of 10 to 12 years old.

Alligators breed once a year, in the spring. 

Males will produce infrasound in the water, which often looks like bubbles released under the water’s surface around the body. He will also slap his head on the water to garner attention. These are to attract a female mate.  

Males will often fight to be the dominant mate as they wait for a female to choose them. Up to 70% of females will choose the same mate again in the following season, displaying some monogamous behavior on the female’s part.

Once paired, a female and male will swim together, touch each other, and produce vocalizations once they have chosen to mate. 

Mating occurs in the open water, with the male inserting his phallus into the female’s cloaca. Fertilization is oviparous, meaning eggs are fertilized internally.

Nesting And Incubation

The female will then build a mounded nest in a marsh-like area with mud, plant material, and sticks. It will be about 3 feet in height and 6 feet in diameter. 

The hard-shelled, white eggs are laid between June and July. An alligator’s clutch can be anywhere from 35 to 90 eggs. The eggs are covered with vegetation to incubate in the nest until they are ready to hatch for about 65 days.

The temperature of the eggs determines the sex of the hatchlings. If the nest is above 91.4°F, the hatchlings will be male. If below 86°F, then the hatchlings will be female. 

Temperatures between 86°F and 91.4°F will result in mixed genders of either male or female.

During the incubation period, the mother protects the nest and males will protect the surrounding territory.

Hatching And Care

In the late summer, the offspring will chirp inside the eggs, and the mother will respond with vocalizations to encourage synchronized hatching. 

The hatchlings chip away at the egg with a sharp tooth on their snouts. This tooth falls off a few days later. If a hatchling needs help, the mother will assist with her teeth.

The mother then carries the born alligators to the water, where they can start eating small prey such as snails, insects, minnows, or tadpoles.

The juveniles stay with their mother for about 2 years, growing rapidly as they eat larger prey such as turtles, carrion, snakes, and raccoons. 


Average Lifespan

Alligators can live up to 50 years in the wild.

However, in captivity, such as in zoos and wildlife refuges, they can live beyond 70 years old.


Intelligence

Alligators have shown many signs of intelligence as compared to other animals. They hunt collaboratively to trap and capture prey. They also use tools, such as sticks on their snouts, to lure birds in for the capture.

Alligators also care for their young from hatching up to 2 years, which is not typical of most reptiles. This length of care demonstrates an intelligent effort and commitment to ensuring species’ survival.

They communicate in various ways including body language, infrasound, and various vocalizations. 

In fact, alligators are loud and can bellow up to 90 decibels, whereas humans can only go up to about 70. At this level, hearing damage can occur. Alligators roar to scare off predators, defend territory, and attract mates.

Alligators have demonstrated intelligence and perseverance when presented with novel situations. 

They can learn patterns and how things work, and adapt their behavior to get to food or water sources. This could include finding a way over an obstacle, noticing the behavior of other creatures, or finding a weak spot in a fence.  


Dangers They Face

Even though alligators are apex predators, they can suffer death and extinction due to dangers in the environment.

According to the International Union for Conservation of Nature (IUCN), American alligators are of the least concern regarding extinction. However, Chinese alligators are critically endangered.

Alligators have the loss of habitat due to human development, wetland drainage, or become roadkill. They can be found eating pets and living in people’s swimming pools. Nuisance alligators on people’s property are either shot and killed or taken to a refuge.  

People also illegally kill alligators, or they may be farmed for the use of their skin in leather products or as meat.

Climate change affects the availability of freshwater habitats, as well as wetland drainage or saltwater inundation or incursion in their water sources. 

In the wild, about one-third of eggs never hatch. Alligators’ eggs and hatchlings are at risk of consumption by other predators, such as raccoons, other alligators, skunks, and opossums.

Bad weather or climate conditions can also prevent eggs from hatching.  

What Animals Eat Alligators?

While man is the biggest predator of alligators for their meat and hide, the alligator can also be consumed by other animals.

Leopards, panthers, and large snakes can attack alligators, though often it is with struggle. Aging, injured, or smaller alligators are easier to overcome.

Eggs, hatchlings, and juvenile (smaller) alligators are more prone to attacks from other animals. 

Nest raiders, such as raccoons and possums will eat eggs. Otters, wading birds, and large fish can eat hatchlings. 

Other alligators will eat juveniles, as well as large predators such as leopards.


Human Interaction

Humans interacting with alligators will be at great risk. There is a risk of death or injury even for professionals trained to work with alligators. 

Alligators cannot be tamed, and do not have emotions. Their brains are wired to be naturally aggressive to find food sources, defend their territory, and mate.


Facts About Alligators

In addition to the information above, here are five more interesting facts about alligators.

1. Alligators Have Ancient Beginnings

Alligators are not dinosaurs, but they existed together. 

They evolved from a group of diverse apex reptiles from over 235 million years ago called archosaur pseudosuchians.

2. They Can Jump, Run, And Climb

Despite their stocky bodies, alligators can jump, run, and climb.

An alligator’s tail contains part of its backbone, making it a powerful propeller for jumping straight out of the water up to 6 feet. 

Their tails also propel them forward on land to lunge to catch prey or push them up as they climb a tree, fence, or other obstacles.

In short bursts, alligators can run up to 30 miles per hour (mph), and 9 to 11 mph for longer periods.

3. Alligators’ Eyes Glow Red

An alligator keeps its eyes (and nostrils) above water as it floats at the surface. While nearly submerged, an alligator can breathe and keep an eye out for prey.

In the dark, an alligator’s eyes will glow. They have a structure called a tapetum lucidum, in the back of their eyes that reflects light into photoreceptor cells. 

This improves their night vision in low light situations. When lights shine on their eyes, they will glow red.  

The greater the distance between the glowing eyes, the bigger (longer) the alligator.

4. They Brumate, Not Hibernate

Alligators are cold-blooded and therefore need to thermoregulate. In colder weather, they do not hibernate but have a dormancy period called brumation. 

Alligators will burrow holes in muddy water and land-adjacent areas, keeping their snouts exposed to breathe.

In this state, their heart and respiratory rates and digestion slow down to conserve energy.

5. Alligator Blood Is Resistant to Bacteria And Viruses

The blood of an alligator has properties that make it antibiotic and antiviral against infections such as HIV-1, Herpes simplex, and West Nile Virus. 

These properties protect the alligators from infection after injury.


Questions About Alligators

1. Are Alligators Lizards?

Alligators are not lizards, even though they seem similar. They are both reptiles, however, alligators have some key differences. 

These include their taxonomic classification (Crocodilia order), semi-aquatic nature, ability to swim, and that they lay eggs only once a year.

2. Are Alligators Bulletproof?

Alligators have thick skin and bony scales, but they are not bulletproof

They have a soft kill spot behind their skull plate, as well as a soft underbelly that a bullet can penetrate.

It takes skill to effectively kill an alligator, and it poses risk to anyone coming close enough to deliver a lethal shot.

3. Do Alligators Breathe Underwater?

Alligators do not breathe underwater. 

This is because they utilize lung respiration, which includes nostrils for breathing when out of the water. However, they are able to ration and conserve breath for expeditions under the water for extended periods of up to two hours.

4. Can Alligators Smell Blood?

Alligators can smell blood, including menstrual blood, up to several miles away with their powerful olfactory systems. 

They cannot smell blood under the water but can detect the odor particles as they reach the water’s surface. 

Alligators use their powerful sense of smell in conjunction with sensory organs on their bodies to detect movement in the water.

5. Can Alligators Live In Saltwater?

Alligators cannot live in saltwater because they do not have salt glands. 

Without salt glands, an alligator cannot remove concentrated sodium and ions from their bodies. Over time, the salt will build up in their blood, resulting in illness, stress, and even death.