MISSISSIPPI GOPHER FROG } Rana sevosa
DESCRIPTION: A stubby frog with ridges on the sides of its back, the gopher frog is uniformly dark above or has irregular dorsal spots; its throat and belly regions tend to be more pigmented. The frog has prominent warts on its back.
HABITAT: Habitat includes both upland, sandy habitats historically forested with longleaf pine and isolated, temporary wetland breeding sites imbedded within this forested landscape. The dusky gopher frog spends the majority of its life in or near underground refugia, and historically has used gopher tortoise burrows for this purpose. But the one remnant population occurs in an area that currently lacks gopher tortoises, although tortoises probably occurred in the area previously and do occur nearby. Refugia include abandoned mammal burrows and holes around old stumps.
RANGE: Formerly, the frog occurred in the Coastal Plain from Alabama to Mississippi and Louisiana, but it now exists in only three ponds in Mississippi: Glen's Pond, Mike's Pond (50 miles east of Glen's Pond), and McCoy's Pond (20 miles west of Glen's Pond). The populations in the latter two ponds are not known to be stable breeding populations.
MIGRATION: A 2001 study indicated that 12 individuals made post-breeding movements that took them 50 to 300 meters from the breeding pond center to terrestrial refugia. Dry conditions that likely limited movements in this study, and information on gopher frog movements in other locations, suggest that longer movements of up to two kilometers are probable.
BREEDING: Adults move to the breeding site in association with heavy rains, usually from January to late March. Studies show annual survival ranges from 65 to 92 percent, but the rate at which adults return to breed among years is about 16 to 22 percent. The average number of seasons in which adults bred was 1.2, but nine individuals bred in three to five seasons. The population turnover rate is high, with most adults living less than seven years.
LIFE CYCLE: Maturation occurs around six to eight months in males and 24 to 36 months in females; most adults live less than seven years.
FEEDING: Young are herbivorous, while adults are invertivores.
THREATS: The frog's range has declined in the past primarily due to urbanization, conversion of longleaf-pine habitat to pine plantations and agriculture, and conversion of open-canopy, temporary ponds to more permanent, closed-canopy ponds. Now, a 4,000-acres residential development has been planned for a site just 200 feet from the frog's main pond. The species is also threatened by the construction and expansion of two highways, a proposed reservoir, pesticides, and drought. An undescribed disease was discovered in gopher frog tadpoles at Glen's Pond in 2003.
POPULATION TREND: Inadequate information is available on the remnant gopher frog population to determine trends, but the species was once believed to occur in nine or 10 counties or parishes in the states of Louisiana (two to three populations), Mississippi (six populations), and Alabama (one population). In 2003, the population had declined to just 100 known frogs breeding in a single, four-acre pond on the DeSoto National Forest in Mississippi. However, in 2004, one calling male was observed at an additional pond and 50 tadpoles were collected from another pond. Still, the most recent surveys suggest there may be fewer than 100 adult frogs remaining.