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 IUCN Red List of Threatened Species lists the gopher tortoise as "critically endangered," primarily because of habitat fragmentation and loss, and human exploitation; the animals are considered threatened in some states, while they are endangered in others.
The gopher tortoise is placed in 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.
Etymology Tortoises of the genus Gopherus are so named because of some species' habit of digging large, deep burrows like those of gophers. The specific name, polyphemus, refers to the cave-dwelling giant, Polyphemus, of Greek mythology. Beolens, Bo; Watkins, Michael; Grayson, Michael (2011). The Eponym Dictionary of Reptiles. Baltimore: Johns Hopkins University Press. xiii + 296 pp. . (Gopherus polyphemus, p. 209).
Description The gopher tortoise is a terrestrial reptile that possesses forefeet that are well adapted for burrowing, and elephantine hind feet. These features are common to most tortoises. The front legs have scales to protect the tortoise while burrowing. G. polyphemus is dark brown to gray-black in overall color, with a yellow plastron (bottom shell). A gular projection is evident on the anterior plastron where the head projects from the shell. Sexual dimorphism is evident, with the male gopher tortoise having a concave plastron, while that of the female is flat. In addition, the gular projection of a male plastron is generally longer than that of a female. Straight carapace lengths of adults usually range from , with a maximum of . The carapace is at least twice as long as it is high. Anal width (distance between the extreme posterior points of the anal shields) and anal notch (distance between the posterior end of the plastron at midline and the posterior edge of the carapace) are dimorphic, but does not become distinctly dimorphic until sexual maturity is attained. Body mass averages , with a range of .Wildlife as Canon sees it . canon.comGopherus polyphemus . Sms.si.edu. Retrieved on 2013-10-21. They are the only extant species of the genus Gopherus found east of the Mississippi River.
Behavior
Diet
Gopher tortoises are herbivore scavengers and opportunistic grazers. Thus, their diets contains over 300 species of plants, with the dominant plants within their environment likely making up the bulk of their diet. They consume a very wide range of plants, but mainly eat broad-leaved grass, regular grass, wiregrass, and terrestrial legumes. However, other plant parts, including shoots, stems, leaves, and pine needles are also eaten. They also eat mushrooms, and fruits such as gopher apple, pawpaw, blackberries, and saw palmetto berries. In addition, gopher tortoises eat flowers from the genera Cnidoscolus (nettles), Tillandsia (Spanish and ball moss), Richardia, and Dyschoriste. A very small portion of the tortoises' diet is composed of fungi, lichens, carrion, bones, insects, and feces, eaten more commonly by females before and after nesting time. Juvenile tortoises tend to eat more legumes, which are higher in protein, and fewer grasses and tough, fibrous plants than mature tortoises. As gopher tortoises usually get water from the food they eat, they usually only drink standing water in times of extreme drought. During wetter seasons, gopher tortoises have been known switch to a more frugivorous diet, seeking out fruits when they are more plentiful. Fruits, being high in sugar and other easily digestible carbohydrates, provide the energy needed for gopher tortoises to mate and burrow.
Burrowing Gopher tortoises, like other tortoises of the genus Gopherus, are known for their digging ability. They spend most of their time (up to 80%) in long burrows. On average, these burrows are long and deep, but can extend up to in length and deep. The length and depth of the burrow vary with the depth of sand and depth of the water table. In these burrows, the tortoises are protected from summer heat, winter cold, fire, and predators, and a variety of activities happen within the burrow and its apron, such as courting and basking in the sun. The burrows are especially common in longleaf pine savannas, where the tortoises are the primary grazers, playing an essential role in their ecosystem. Except during breeding season, gopher tortoises are solitary animals, inhabiting a small home range. Within their range, they dig several burrows. On average, each gopher tortoise needs about to live. In addition to providing a shelter for themselves, gopher tortoise burrows are used by 60 vertebrate species and 300 invertebrate species,Marshall, Craig D.; Maerz, John C.; Larsen-Gray, Angela L.; Martin, James A. (2024). "Gopher Tortoise (Gopherus polyphemus) Vertebrate Burrow Commensals within a Private, Working Forest Landscape". Ichthyology & Herpetology 112 (2): 188–195. (7 June 2024). including many rare species (i.e. eastern indigo snake, gopher frog, and Florida mouse). The term that describes these species, as well as others that use the burrows, is "commensals". Because of the importance of their burrows, gopher tortoises are known as keystone species; without them, the biodiversity of their respective ecosystems will deteriorate.
Movement The species is known to move short distances when foraging and seems to stay within 100 m or less, but when on the hunt for a new foraging site, gopher tortoises may travel up to 2 miles. Their activity levels vary depending on temperature, with activity increasing alongside the spring and summer's warmer months.
Life span
Gopher tortoises can live more than 40 years.Parham, James (2010) "Gopherus polyphemus DAUDIN 1802" , Encyclopedia of Life. One current specimen, Gus (age 104—the oldest known living gopher tortoise—as of 2026), has been living continuously in captivity at the Nova Scotia Museum of Natural History in Halifax for 84 years and is believed to have hatched between 1920 and 1925. Additionally, a specimen in North Texas reportedly has a verified age of 75–78 years old.
The gopher tortoise reaches maturity around 10–15 years of age, when its shell is around long. Male tortoises reach adulthood around 9–12 years of age, and females take up to 10–21 years to reach maturity. Maturation time may vary based on local resource abundance and latitude. Gopher tortoises prefer to live solitary lifestyles, burrowing alone and only breaking this during mating season
Breeding and reproduction
Gopher tortoises reach sexual maturity between 9 and 20 years of age, depending on sex and what region the species chooses to populate. Sexual reproduction involves courtship rituals. During the mating season, females only produce one clutch annually between April and November, females lay up to 25 eggs. The clutch size is positively correlated with female plastron length.Landers JL, Garner JA, McRae WA (1980). "Reproduction of Gopher tortoises (Gopherus polyphemus) in southwestern Georgia". Herpetologica 36: 353–361. These clutches are incubated underground for 70–100 days. The sex of the eggs is determined by the temperature where they are incubated in a nest laid below sand. If the sand is over 30 °C, hatchlings are female and if below 30 °C, they are male. Incubation can last from 80 to 90 days in Florida and 110 days in South Carolina. The eggs stay in the uterus of the female for 60 days until oviposition occurs; they their uterine epithelium to supply "pumping water" and transport important nutrients to the eggs.
Gopher tortoises may mate from February through September, with a peak throughout May and June. Females typically lay clutches of 3–14 eggs, but can lay up to 25, depending on body size, in a sandy mound very close to the entrance of their burrow. Reproduction rates and clutch sizes are positively impacted by higher temperatures. Warmer temperatures stimulate a female gopher tortoise's endocrine system, which helps trigger vitellogenesis, or yolk formation.
About 90% of clutches may be destroyed by predators such as armadillos, raccoons, foxes, skunks, and alligators before the eggs hatch, and fewer than 6% of eggs are expected to grow into tortoises that live one year or more after hatching. As the tortoises age, they have fewer natural predators. Egg predation rates are unchanged regardless of whether nests are close to or remain far from burrows. Additionally, a denser soil composition may affect hatchlings' ability to emerge due to their apparent inability to dig themselves out of the nest.
Each hatchling has a straight carapace length of .
Social behavior Gopher tortoises, more than other tortoise species, are thought to exhibit social behavior. While primarily solitary creatures, they live in well-defined colonies that are similar to those of highly social animals such as the prairie dog. The distribution and proximity of burrows might be the consequence of social relationships between tortoises. Both males and females have been found to use chemical signals to communicate with each other. These chemical signals are secreted from the tortoises' mental gland on their chins.
Some females have been observed visiting the burrows of a particular female repeatedly, even if other tortoises are nearby. This may be a sort of "friendship", but such terms are not normally used to describe the relationships between animals. Female gopher tortoises generally do not relocate once they have moved into a colony, and larger males usually have their burrows adjacent to females in the spring. Males can travel up to to visit females and their burrows. Juvenile gopher tortoises have been known to occasionally cohabitate burrows, but this hinders their ability to escape or deter predators. If one juvenile blocks another from entering or moving within the burrow, aggression and occasionally combat may ensue.
Conservation concerns Historically
Since July 7, 1987, the U.S. Fish and Wildlife Service (FWS) has listed Gopherus polyphemus as "threatened" wherever the tortoises are found west of the Mobile and Tombigbee Rivers in Alabama, Mississippi, and Louisiana. On November 9, 2009, the FWS proposed rulemaking to include the eastern population of G. polyphemus in the List of Threatened Wildlife. In October 2022, the FWS announced that the species overall and its eastern distinct population segment (DPS) did not warrant listing at that time. G. polyphemus appears on the IUCN Red List as a "Vulnerable" species; however, it has not been assessed for the purposes of this list since 1996. In July 2011, the FWS determined that listing the eastern DPS as threatened under the Endangered Species Act is warranted, but it is precluded from doing so at this time due to higher priority actions and a lack of sufficient funds to commence proposed rule development. In the interim, the FWS would place the eastern DPS on its candidate species list until sufficient funding is available to initiate a proposed listing rule. In 2018, the IUCN Tortoise and Freshwater Turtle Specialist Group recommended a reassessment and reclassification of all six Gopherus species This reclassification would move G. polyphemus from vulnerable to endangered. NatureServe considers the species to be Vulnerable.
The Conservation Clinic at the University of Florida's Levin College of Law describes five main threats to the tortoise population - habitat loss through human development, habitat loss through poor supervision, human desire to use it as a pet or eat it as meat (see human predation), relocation causing population disruption, and disease caused by relocation.