Fox Squirrels of Florida
Sherman’s and Big Cypress species inhabit Southwest Florida
THE FLORIDA FISH AND WILDLIFE CONSERVATION COMMISSION (FFWCC) HAS DESIGNATED THE SHERMAN’S FOX SQUIRREL AS A “SPECIES OF SPECIAL CONCERN” AND THE BIG CYPRESS FOX SQUIRREL A “THREATENED” SPECIES.
Three species of fox squirrels are native to Florida: Sherman’s ( Sciurus niger shermani), southern ( S.n. niger) and Big Cypress ( S.n. avicennia). Other Florida squirrels include the southern flying squirrel
( Glaucomys volans) and gray squirrel ( S. carolinensis). Of the state’s three fox squirrel species, the Sherman’s and Big Cypress can be found in Southwest Florida, while the southern fox squirrel lives in the Panhandle. The Florida Fish and Wildlife Conservation Commission (FFWCC) has designated the Sherman’s fox squirrel as a “species of special concern” and the Big Cypress fox squirrel a “threatened” species.
The range of the Sherman’s fox squirrel stretches north of the Caloosahatchee River into Georgia. The Big Cypress fox squirrel ranges south of the Caloosahatchee River and west of the Everglades. Both squirrels have a white muzzle and white ears, black cheeks and crown and variable pelage coloration. Sherman’s fox squirrels generally appear uniformly tan, while a rare few are totally black. The Big Cypress fox squirrel is mostly orange-buff to rust with a dark back. The Sherman’s fox squirrel averages 25 inches in total length (head, body and tail) and weighs 2.5 pounds, while the slightly smaller Big Cypress fox squirrel is 21 inches in total length and weighs 2 pounds.
Habitat for the Sherman’s fox squirrel consists of open upland pine/oak communities characterized by a mixture of mastproducing trees, primarily pine/oak assemblages. This squirrel also uses upland hardwood forests and bottomland and cypress domes if they are interspersed with or adjacent to pine/oak communities. In south-central Florida it uses improved savannalike pastures that are similar to native pine/oak habitats. It will also use golf courses and suburban parks. The Big Cypress fox squirrel lives mostly in slash pine flatwoods and cypress forests that include tropical hardwood hammocks, mangrove forest, live oak woods, parks and golf courses. The cabbage palm ( Sabal
palmetto) is a common component of these habitats. The home range of the male fox squirrel averages 100 acres in Florida, while home range for the female averages 50 acres. Male home ranges overlap but their core areas do not. The male does not defend his core areas. Female home ranges do not overlap as extensively as male home ranges, but the female aggressively defends her core area from other females. The fox squirrel can travel up to 1.2 miles per day. The Sherman’s fox squirrel eats acorns, slash pine ( Pinus elliottii) and longleaf pine ( P. palustris) seeds. Other foods include bulbs, vegetative buds, mushrooms, insects, staminate pine cones, corn, peanuts and pecans. Acorns are collected in late September; some will be cached. Pine cones are taken while green from May through October.
The Big Cypress fox squirrel prefers slash pine seeds. It harvests female slash pine cones ( macrostrobili) during the summer and the male cones ( microstrobili) during the winter. During the fall and winter the Big Cypress fox squirrel feeds on cypress ( Taxodium spp) cone seeds, as well as acorns, mushrooms, queen palm ( Cocos pamosa) fruit, cabbage palm fruit, fig ( Ficus spp) fruit and bromeliad buds.
One of the most important habitat components for each of these fox squirrels is food availability. During years of limited acorn production seasonal habitat use patterns are greatly affected, and complete reproductive failures will occur.
Fox squirrels are sexually mature at nine months of age. In Florida the two subspecies have two pronounced breeding seasons. One extends from late November through January, and the other from early May through August. Females usually produce only one litter per year. Mean litter size is two, and the young remain in the nest for approximately 75 days. They are weaned when they are 3 months of age. It is not known how long Florida fox squirrels live in the wild, but in captivity they have lived for 13 years.
In Florida the fox squirrel rarely nests in true cavities but prefers platforms of twigs, leaves, Spanish moss ( Tillandsia usneoides), pine needles and other vegetative material. The nest of the Big Cypress fox squirrel also includes strips of bark from cypress and melaleuca ( Melaleuca quinquenervia) trees. This subspecies places its nest in cypress, melaleuca, slash pine and oaks. It constructs as many as 30 nests per year and will use each nest for shelter once or up to and greater than 10 times. The Sherman’s fox squirrel places its nest high in oak trees and sometimes in longleaf pines.
The population of Florida fox squirrels has been declining over the past three decades from the conversion and loss of its primary habitat of longleaf pine and slash pine–dominated forests.