Eastern Cottontail

(Sylvilagus floridanus)

 

Physical Description

US Fish and Wildlife Service photo (http://images.fws.gov/)

The Eastern cottontail rabbit is a small mammal. It is usually 14 to 19 inches from head to tail, and 6 to 7 inches from feet to shoulder. It weighs 2.5 to 3.5 lbs. Females may be slightly larger than males. It is similar in appearance to the varying hare, but is smaller, stockier, and has less-specialized hind legs. In the wild, a cottontail will live to be about 4 years old, but in captivity may live to be 10 years old.

 

The Eastern cottontail has thick, soft fur. It molts once a year, but its coat color does not change with the seasons. The coat color may be buff, ochre, brown, or grey on various parts of the body. The coat has black-tipped guard hairs dispersed throughout. The stomach, chin, insides of the legs, and the underside of the tail are all white. The bright white tail is what gave the cottontails their name. It also has a white spot on the forehead, between the eyes. The fur is not waterproof. The New England cottontail is a subspecies that is very similar to the Eastern cottontail, and can be distinguished by its black patch of fur between the ears.

 

The Eastern cottontail has large ears, ranging from 2.5 to 3 inches in length. They are lightly furred on the outside, and almost bare on the inside. The skin is very thin, with blood vessels easily discernable. The ears are always flicking back and forth, listening for predators.

 

The Eastern cottontail has large eyes that protrude from either side of the head, giving it almost 180º vision. It does have a blind spot directly in front of its face, so cottontails often look at things with their head slightly turned to one side.

 

Like most rabbit species, the Eastern cottontail has a cleft upper lip. It has long, light-colored, unnoticeable whiskers. It has 28 teeth (10 premolars, 12 molars, and 6 incisors). There is a large gap in the teeth between the incisors and premolars.

 

The Eastern cottontail uses its nose mainly for locating food, rather than sniffing out predators. However, the nose is always kept wriggling in order to help pick up the sent of nearby predators.

 

The feet of the Eastern cottontail have a dense covering of fur, which covers the pads. There are 5 toes on the forefeet and 4 toes on the hind feet. The hind legs are about 12 inches long and are powerfully muscled.

 

The bone structure of rabbit forepaws prevents them from being turned inwards, so that, unlike rodents, rabbits cannot use their forepaws to grasp objects. The Eastern cottontail in particular has some other interesting skeletal features that help distinguish it from other rabbit species. It has broad, heavy supra-orbitals with an anterior marked notch. The inner side of the post-orbital process touches the skull along almost its entire length. The bullae are large.

 

The Eastern cottontail has a 28-day gestation period. The young are born without fur and with their eyes closed. They weigh about 1 oz each and are about 4 inches long. The young grow rapidly on the mother’s milk, which is 13% butterfat. By the end of the first week, the young will by fully furred, able to open their eyes, and move around. By the end of the second week, the young will begin to leave their nest area for short periods of time. By the end of the third week, the young will be entirely weaned. At the end of seven weeks, they will leave the nest.

 

Notable behaviors

Eastern cottontails are crepuscular, active between 4:30 am and 7 am, and then again at 5 pm until dark. The Eastern cottontail will spend most of its daylight hours in a form, unless harsh weather forces it to seek better shelter. The form is a well-hidden spot beneath a grass clump or in a thicket. In the winter, forms are usually on the sunny southern faces of hills. Frequently-used forms will have the vegetation of the floor worn away. Grasses may meet overhead, forming a kind of roof. Within the form, the rabbit cannot be seen, but is able to detect danger.

 

Although the Eastern cottontail is capable of digging burrows, it does not. Burrows represent the possibility of being trapped in a dead-end. Weasels are more comfortable in burrows than cottontails, and so if there are any weasels in the area, the cottontail will absolutely never use a burrow. If a cottontail is found in a burrow, it is usually in wintertime and in a burrow that has been abandoned by another animal. The cottontail will site about 6 ft away from the entrance of the burrow, in enough to be warm and close enough to the exit to flee at the first sign of danger.

 

Whenever the Eastern cottontail senses danger, it will immediately escape onto one of its well-tended paths. A cottontail bounds, rather than runs. In a bound, the front feet come down, one in front of another, and then the hind feet come down side-by-side in front of the front feet. The rabbit may cover up to 15 feet in a single bound, reaching a top speed of about 20 mph. It will often move from side to side, making a zigzag pattern to break up its scent trail. Occasionally, it will make an extra-high leap in order to observe what is going on around it.

 

The Eastern cottontail does not make a lot of vocalizations. It may, however, thump the ground with its hind legs to signal to other rabbits that there is danger nearby. It will emit a piercing scream when caught by a predator. The sound of the scream carries well and usually attracts more predators to the area.

 

The Eastern cottontail has an extremely varied diet. Summer foods include, but are not limited to: poison ivy, bluegrass, crabgrass, other grasses, broad-leafed plants, all berries, all fruits, cultivated crops (wheat, soybeans, alfalfa, clover, lettuce, cabbage beans), weeds (goldenrod, yarrow), wild shrubs, sheep shorrel, wild cherry, and the bark of most trees. The fact that most fruit trees will die when their bark is stripped has turned many an orchardist against the Eastern cottontail. Such animosity could be avoided if the orchardist left pruned branches on the ground because they more appealing to the Eastern cottontail than the bark. A favorite winter food of the Eastern cottontail is sumac, because its roots are high in fat. A cottontail will dig through snow to reach food, but will not dig through dirt. It meets its water requirements by eating snow, dew, and plants with high water contents.

 

The Eastern cottontail breeds from January or February until August. A female can have up to 6 litters per year, but 3 is average. The month of May sees the peak in cottontail breeding because the weather, temperature, and amount of available food are normally ideal.

 

At the end of December, male Eastern cottontails will begin fighting for the right to breed. Two opposing rabbits will rake the grass with their forepaws and circle each other, looking for a chance to bite. They may rise up on their hind feet to box, or leap over each other to kick with their hind legs. The lesser rabbit will run off. The dominant rabbit will not pursue, but instead begin to fight the female.

 

A male Eastern cottontail must fight the female in order to impress her. He will jump to avoid her charges, possibly hit her, and jump over her and squirt urine. When the female is suitably impressed, she will allow copulation. Copulation takes only a few seconds, and may occur several times. A female will accept multiple mates in one breeding season.

 

When the female is pregnant, she will dig a saucer-like impression in the ground (likely the only kind of digging she will ever do). She will pull fur from her belly and mix it with dead grass to form a blanket over the depression. She will normally give birth to about 5 young. As soon as the young are born, she will cover them and immediately go off to breed again. The female will not let her mates stay in the same area as her nest, because the males may kill the young of their rivals. The female will guard her nest from several feet away during the day. At night, she will allow the young to suckle several times.

 

Enemies of the Eastern cottontail include weasels, mink, skunks, raccoons, cats, dogs, foxes, bobcats, coyotes, hawks, owls, constrictor and rattler snakes, lice, ticks, mites, bot flies, round worms, pinworms, tapeworms, Tularemia, rain and snow storms, fire, plows, and human hunters. Tularemia is a disease shared by rabbits and humans, and affects the lymph glands, liver, and spleen. A rabbit with Tularemia will be lethargic and unable to run, even when in danger. Tularemia is spread through blood, so if you hunt a rabbit that you suspect is infected, wear gloves when handling it and check for white spots on the liver.

 

Species Distribution

The Eastern cottontail can be found from Canada east of the Rocky Mountains, down to the Gulf of Mexico. It also ranges from the southern mountains in Arizona to the east coast. It is found in much of New England, but not the most northern New England states. It can be found from sea level to up to 6,000 feet on mountains.

 

Habitat Requirements

The Eastern cottontail prefers areas with a lot of good cover, such as brush, forest edges, swamps, thickets, and weedy fields. The female range is a few acres, while the male range is larger. The cottontail is always intimately familiar with every aspect of its range, and maintains escape paths by chewing away obtrusive bushes, branches, and grasses.

 

It is difficult to find signs of an Eastern cottontail in the summer, but in winter the signs are easily recognized. Look for brown droppings, tracks in the snow, and trees that have had their bark pealed off.

 

References

Goodwin, George Gilbert. 1935. The Mammals of Connecticut. State Geological and Natural History Survey. Hartford, CT.

“Natureworks: Eastern Cottontail – Sylvilagus floridanus”.2006.  http://www.nhptv.org/Natureworks/easterncottontail.htm

Rue III, Leonard Lee. Complete Guide to Game Animals: A Field Book of North American Species. 1981. Grolier Book Clubs, Inc. United States of America.

 

 

Information gathered and reported by Jessica Donnelly, ENWC 201 Fall 2006