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Cottonmouth vs Rat Snake: Key Differences Explained

The cottonmouth is a deadly viper that can kill human beings. The rat snake, on the other hand, is non-venomous constrictor. Both share a similar diet of small mammals, birds, and other reptiles, but the cottonmouth can take on larger prey including small crocodiles.

Cottonmouth vs Rat Snake: Key Differences Explained

However, the rat snake possesses some skills that makes it a formidable hunter. Even if it does not eat snakes, it still is a powerful constrictor

Disclaimer: This is information for entertainment and educational purposes only. Do not approach a wild animal and keep your distance. Only professionals should handle wild animals. Seek professional help immediately if you have been bitten or otherwise harmedConsult your local wildlife authority for the right advice for your situation and locality.

FeatureCottonmouthRat Snake
1. Scientific NameAgkistrodon piscivorusFamily: Colubridae
2. Size48 inches6 feet
3. ColorsLight to dark brown with crossbands and specklesYellow, black, brown, red, orange, gray, etc
4. RangeEastern and South USNorth America, Central America, Southern Canada
5. Hunting BehaviorOpportunistic hunterConstrictor
6. Breeding SeasonApril to MayLate spring
7. Lays EggsNo (ovoviviparous)Yes
8. Pet BehaviorFor experts onlyCan be kept as pets
9. VenomousYesNo
10. Life Expectancy10 years in the wild; 24 in captivityUnknown
11. DietVertebrates, birds, amphibians and fish other snakes, baby crocodiles and turtlesMice, other rodents, birds, lizards, eggs, and frogs.

Cottonmouth Overview

The cottonmouth is a semi-aquatic snake that thrives in the United States. It is venomous and has enough toxicity to kill a human being. However, reports of bites are rare, as they are not as aggressive as other snakes. 

The cottonmouth is also called the water moccasin because of its preferred habitat, which is close to bodies of water. It is not unusual to find a cottonmouth near ponds, lakes, mangroves, and the riverbanks. 

Read More: Do Ponds Attract Snakes?

The name of the cottonmouth comes from its white mouth, which it opens wide open when under threat or duress. The snake itself is part of the viper family and shares some physical resemblance with them. 

The cottonmouth has a triangular head, and its eyes are slit, like a cat.

Typically, a cottonmouth is light brown, with bands that are dark brown. It also has spots or speckles, which are usually darker brown than the bands. Adults often get darker, and they can look black to the untrained eye.

You can spot cottonmouths throughout the day, however, they primarily hunt at night. They are the only water-loving snakes in the entire country of the United States. 

The cottonmouth likes basking in the sun. They live in logs, rocks, and tree branches. They go down for a swim when they want to hunt for fish. Despite being able climbers, they rarely go up to the higher parts of trees.

The cottonmouth is a hunter and an ambush predator. It eats a wide array of animals that include small turtles, baby alligators, birds, and fish. It is one of the few snakes that can digest fish with no problem. 

Rat Snake Overview

The rat snake is not a single species of snake. It belongs to an entire family, and it has many subspecies. The rat snake is a member of the sub-family of Colubrinae. Specifically, it belongs to the family of Colubridae, which means it is a constrictor.  

The rat snake is of medium to large size. It can grow up to six feet, but this size is debatable as to the type of rat snake in question. The rat snake is not venomous and is a docile pet for humans. 

There are two types of rat snakes called the Old World and the New World. The Old World refers to the Eastern Hemisphere rat snakes, while the New World refers to those in the Western Hemisphere. 

Both these types are genetically different. The New World rat snakes are common in North America. They earned the name because they primarily feed on rats. They typically hang out in grain mills where rats are common.

The rat snake comes in many colors and names. For names and subspecies, below are some examples:

  • Eastern rat snake
  • Texas rat snake
  • Yellow rat snake
  • Red rat snake
  • Gray rat snake

One type of rat snake is the corn snake, and it is called so because it is commonly seen in corn grain storage or barns where they also hunt for rats.

Overall, there are 40 to 55 known species of the rat snake. Although they are mostly found in the US, they also found their way in other geographical locations such as in Europe and Asia. There are rat snakes in the Philippines, too.

The Philippine rat snake is brown to reddish and is known in the international community as the Reddish Rat Snake. 

In the wild, rat snakes live in woodlands and hunt rats. Despite rats being their favorite meal, they also eat eggs. Some of them eat chicken eggs, and this is why they are also sometimes referred to as chicken snakes.  

Cottonmouth vs Rat Snake Comparison

1. Appearance

A corronmouth snake in the water

The cottonmouth is light brown with dark brown bands and speckles. It does look like a formidable snake as it is thick. The adults are black. 

The rat snake is much more difficult identify as it comes in many colors. Most of the time, the rat snake that people refer to is black. This type of rat snake is the Eastern Black Rat Snake

The rat snake can be black, light brown, and reddish orange. Some rat snakes are gray with black speckles. The corn snake, which is a type of rat snake is orange with dark orange spots. 

2. Venom

The rat snake is not venomous, and no species of it has venom. All of them come from a family of colubrids

On the other hand, the cottonmouth is deadly. As a pit viper, its venom is made of enzymes that cause the destruction of local tissue. Unlike other powerful venomous snakes, its venom is not a neurotoxin. 

The venom destroys the metabolism of the cellular membranes. The reaction is inflammatory and can result in death. Envenomation or bites are uncommon.

Little is really known about the venom power of the cottonmouth. If bitten, professionals in the medical industry have to administer something called Crotalidae polyvalent immune fab (CroFab) antivenom.

3. Habitat

Rat Snake

The cottonmouth or water moccasin likes to live close to bodies of water. In their respective geographical locations, they can be found nearly in all types of bodies of freshwater. One could expect to see them in mangroves, ponds, lakes, and swamps. 

Rat snakes are more flexible. While they also live in wetlands, they are easily adaptable to areas where here is human civilization. They hunt rats in rice fields and rice grains. 

In the wild, it is not uncommon to see rat snakes in swamps, floodplains, mountains, and hardwood forests. They also live in urban parks and farms.

4. Reproduction

Rat snakes lay their eggs in logs. They also do this under compost, leaves, and sawdust piles. Some lay eggs in hollow trees. 

As oviparous snakes, they do not spend so much time incubating their eggs after laying them. Mating season is typically in late spring. If it is cold, they may not lay eggs at all. 

Cottonmouths give birth to live young. The litter size is between one and twenty. Cottonmouths reproduce once every two years. 

The cottonmouth’s mating season is in the summer. During this period, male-to-male combat happens because they have to fight for the female’s attention. 

5. Pet Viability

Cottonmouth

Cottonmouths are not great pets. They are dangerous and can kill the owner or anyone who makes a mistake in handling them. 

As far as feeding is concerned, they are versatile snakes. They eat almost anything, even fish. The water moccasin is one of the few species of land snakes that can digest fish properly. 

The rat snake is an ideal pet because it is docile. The absence of venom makes it safe. Despite it being a constrictor, it is not powerful enough to kill a human being, instead feasting on small mammals, birds, and eggs. Although not venomous, its bite is still dangerous and may pose a threat to small children.

6. Hunting

The cottonmouth is an active hunter. As a pit viper, it senses its prey with its infrared vision. It attacks to bite and waits for its prey to die. The cottonmouth is an ambush predator. It hides and waits for its prey, and then strikes.  

This ambush technique is what they use to hunt rats. Some of them kill several prey at a time. 

Summary: Cottonmouth vs Rat Snake

snake eating bird

Between the cottonmouth and the rat snake, the cottonmouth is clearly the winner. It is a venomous animal that has the ability to heat sense, and it can hunt in water. 

The rat snake, however, depends on its constricting abilities. It has a powerful muscle, but it does not eat snakes. Its cousin, the kingsnake, is a better representation of its family as far as superiority is concerned. 

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