GOPHER TORTOISE

(Gopherus polyphemus)


Web page Created by Russell Zetterlund

CLASSIFICATION: The Florida gopher tortoise (Gopherus polyphemus) is a reptile whose lifespan can exceed 100 years. And like all turtles, has a bulky shell on its back for its primary defense. The genus Gopherus consists of tortoises in North America that are adapt at digging and burrow. The species name polyhemus given in 1802 by the French scientist Francois-Marie Daudin who gave this name to the burrow dwelling tortoise after the cave-dwelling Polyphemus, the legendary Cyclops of the Iliad. The gopher tortoise in currently considered a threatened species and is protected everywhere except Florida, where it is a listed as a Species of Special Interest by the Florida Fish and Wildlife Conservation Commission.

APPEARANCE The gopher tortoise is a land turtle, usually between 6 and 15 inches long and weighs an average of 9 pounds. It is gray or dark brown on the top of its shell with a yellowish plastron (undershell). The tortoises claw-tipped front legs are strong and shovel-like, great for digging burrows. They also help the tortoise carry its heavy shell.

When determining the sex of a tortoise, the most noticeable difference is that the male's plastron is concave (above right), whereas, the female's is perfectly flat (above left).

RANGE: Gopher Tortoises generally live in the Southeastern U.S. They primarily live in Georgia and North and Central Florida, but can be found any where from Southeastern Louisiana to Southeastern South Carolina and all throughout Florida.

HABITAT: They like to live in dry sandy places near woods or grass. The gopher tortoise digs burrows that are 10 to 50 feet long, and often have more than one tunnel. They will generally spend 60-70% of their adult life in their burrows. When the tortoise is not underground at home, it might be warming up in the sun or looking for food.

 

FOOD: Gopher Tortoises eat grasses and weeds, but can also eat fruits and mushrooms. Some of their favorite foods consist of gopher apples, saw palmetto berries, and the prickly pair cactus. They have also been known to eat the bones of small animals (most likely for calcium).

REPRODUCTION: In most species of tortoises (if not all) the male's tail is much longer than the female's. The male uses this tail to impregnate the female by climbing onto  her back and inserting his sperm into her. The female will lay anywhere from 3 to 15 eggs (the average is about 6) in a clutch. She will lay one clutch every year. The eggs take about 100 days to hatch.

HATCHLINGS: When the baby turtles hatch they about 1.5 to 2 inches long and only grow about an inch a year. In addition their shells are quite soft at birth. To make matters worse their are not there to protect them. These facts leave the new-born turtle pretty much defenseless. When a hatchling is born the first thing it must do is seek shelter. It will either dig a small burrow for itself, climb in adult turtle's burrow, or hide itself in nearby bushes or foliage. Like many other reptiles, gopher tortoises have temperature-dependent sex determination. That means that when the eggs are laid, they are neither male nor female. The sex of the offspring is determined by the temperature of the sand or dirt where the nest is incubating. For gopher tortoises, if the temperature is above 30° C (85° F), the hatchling tortoises will be females. Temperatures below 30° C produce males.

BURROWS: In east-central Florida, burrows average 4.5 m (15 ft.) long and 2 m (6 ft.) deep. The tortoise digs the burrow at about a 30 degree angle from the surface. Having a burrow provides protection from predators, fire, and the weather. The burrow has a fairly constant environment that is not too hot, too cold, too humid, or too dry. This is very important for cold-blooded animals. The open sandy area in front of the burrow, called the apron, is often used by the female tortoises for a nest site.

IMPORTANCE: Tortoise burrows provide homes for other animals, including snakes, frogs, owls, and mice. These burrows are very important during forest fires, because they give many animals a safe place to hide. In addition, their droppings play an important role in the spreading of the seeds of many of the plants they eat.

 WHY THREATENED: While not yet on the Endangered Species list, the gopher tortoise's numbers are growing scarce. The biggest reason for this is loss of habitat is due to the building of cities and homes. They are also frequently run over by cars while crossing the road. Predators also prey on eggs and hatchling. The newest threat to gopher tortoise populations is Upper Respiratory Tract Disease (URTD). This extremely contagious and nearly always fatal illness is caused by the bacterium Mycoplasma agassizii. Symptoms include an inflamed respiratory tract, wheezing, runny nose, and swollen eyelids. An infected tortoise eventually starves to death because it can not find food or eat. A test that detects antibodies for URTD in tortoise blood has been developed, but so far, there is no vaccination against the disease, nor is there a cure. Tortoises that test positive for the disease do not always show symptoms. URTD is spread between populations by the introduction of a diseased tortoise into a healthy population.

WHAT IS THE LAW? It is against the law to keep a tortoise as a pet or to play with a wild tortoise. The best thing to do is to leave them alone. It is also illegal to transport tortoises because of the risk of spreading URTD. Even if a tortoise is in a habitat that is scheduled to be destroyed, the best thing you can do is notify the Florida Fish and Wildlife Conservation Commission or some other organization certified to handle gopher tortoises.  If a tortoise is in the middle of a busy road, you are permitted to help them across in the direction they are headed. Otherwise, please do not disturb these creatures, as they are a vital part of the ecosystem of Florida and other states in the Southeastern U.S.

BIBLIOGRAPHY:

1. Gopher Tortoises

http://www.nbbd.com/godo/ef/gtortoise/
 
 

2. Gopher Tortoises--"Ask the Expert"

http://www.nbbd.com/godo/ef/gtortoise/QandA.html
 
 

3. What's in a name?

http://www.tortoise.org/archives/gophname.html
 
 

4. Gopher Tortoise

http://atlas.ksc.nasa.gov/threat/tortoise.html
 
 

5. Tortoises

http://www.nsis.org/wildlife/rept/turt-tort.html