Gopher Tortoise

## Description

The gopher tortoise (Gopherus polyphemus ) is a species of tortoise in the family Testudinidae. The species is native to the southeastern United States. The gopher tortoise is seen as a keystone species because it digs burrows that provide shelter for at least 360 other animal species. G. polyphemus is threatened by predation and habitat destruction.

The gopher tortoise is a representative of the genus Gopherus, which contains the only tortoises native to North America. The gopher tortoise is the state reptile of Georgia and the state tortoise of Florida.

## Appearance

The Gopher tortoise is one of a group of North American land tortoises that originated 60 million years ago, and is therefore one of the oldest species alive today. They are named for their ability to dig big, deep burrows. Their burrows are often used by a range of other species in the ecosystem, making these animals a keystone species having a pivotal role in their native community. They have front legs like shovels that help them dig, and they have strong sturdy back legs. Like all tortoises, the undersides of the males’ shells are concave, which is different to the females. They also have longer tails, and their shells, which they use for butting or ramming, extend under their chins, but females are larger.

## Distribution

The Gopher tortoise lives in the south-east of the United States, in south-western South Carolina to the Florida peninsula, as well as west to Louisiana. It prefers dry landscapes like sand dunes and sandy ridges, as well as forests of longleaf pine.

## Behavior

The Gopher tortoise is diurnal and active at any time of the year with activity peaking in May or June. Excavation of burrows is the main activity, which they dig with their forelegs, up to 12 meters long and 3 meters deep. Their burrows provide a place to sleep or hibernate, protected from both enemies and harsh weather. These solitary tortoises emerge each day in warm weather after a night in their burrows, generally in the morning before it gets too hot, to forage for food. Every tortoise has its own well-defined home range, containing several burrows. Males will travel farther than females, particularly during the breeding season, with the size of the home range depending on how much groundcover vegetation there is. The more vegetation, the smaller the range.

## Diet

The Gopher tortoise is generally a herbivore (folivore) that eats low vegetation, mostly grasses and leaves, as well as occasional berries and wild fruits. In captivity, these tortoises enjoy watermelon and cantaloupe rinds.

## Reproduction

Gopher tortoises have a polygynous mating system, in which a single male will mate with multiple females. Mating is from April through November, with peaks in August and September. At this time, males will visit the burrows of the females in their colonies and make short rasping calls in order to attract them. Males and females may engage in fighting, apparently as part of courting. Eggs are laid typically from mid-May until mid-June in a sunny open place. 1 to 25 white eggs of a spherical shape are laid in holes dug in the ground in batches of five or six. The tiny hatchlings have to dig to the surface on emerging 100 days later. Their gender is determined by the temperature during incubation, so those at over 30 ºC are the females, and the males are those below 30 ºC. The hatchlings are given some protection by their parents in deep, long burrows, but are still under threat by raccoons, skunks, foxes, armadillos, and opossums. They are reproductively mature at 10-25 years

## Population

### Population threats

The main threat to this species is loss of habitat as a result of development, natural areas and forest being converted for intensive agriculture, and poor land management practices, such as pesticide use or fire suppression. Gopher tortoises have been poached in the past for meat, but now are more commonly poached for pets. Pet Gopher tortoises may not be harmed but they are not able to mate and this can mean serious population declines. Currently, road deaths are probably the most common way that humans cause the death of Gopher tortoises.

### Population number

According to the Animal Spot resource, the total population size of the Gopher tortoise is about 1,674,000 individuals. According to the Defenders of Wildlife resource, the total population size of this species in Florida in 2003 was estimated to be under 800,000 individuals. Overall, currently gopher tortoises are classified as Vulnerable (VU) on the IUCN Red List.

### Ecological niche

Gopher tortoises are a “keystone species”. Their burrows offer a vital refuge for not only the tortoise but other species that have adapted to the fires occurring naturally in their native ecosystem. These wildlife species that live in their burrows or seek refuge in them are called commensals, and there are nearly 400 of them. Another Gopher tortoise behavior of benefit to the native community is the way it feeds. It “prunes” the plants it feeds from, usually leaving the plant healthy and ready to send out nutritious new growth, and the seeds get fertilized and distributed throughout its home range.

## Fun Facts

This tortoise is unique in making large burrows, which few tortoises do, many of them hiding under vegetation or using very shallow burrows.

A Gopher tortoise is ectothermic. It cannot regulate its own body temperature, and so relies on its environment to keep it at a healthy temperature. It often basks in the sun in order to warm itself, and its burrow keeps the temperature regulated throughout all seasons.

The mouth of the Gopher tortoise burrow is a distinct half-moon shape.

Gopher tortoises are in their burrows for 80% of their life.

Historically, there used to be so many Gopher tortoises in the southeast that the native Americans commonly made use of their shells for pots, baskets and even helmets.

A Gopher tortoise is rarely seen drinking from water which is standing. It is able to dam up water with its front flipper-like legs as the water runs down its burrow when it is raining. Most water they get comes from their food.