Key Largo woodrat

Identification

The Key Largo woodrat (Neotoma floridana smalli) is a nocturnal 7-9-ounce rodent that is reddish above, cinnamon on the sides, and has a cream or white belly coloration. Its forefeet are white to the wrist and hindfeet are white to the ankles. It has large ears, protuberant eyes, and a hairy tail unlike it’s nonnative competitor, the black rat (Rattus rattus) which has smaller ears and a naked, scaly tail. The head-and-body-length of the Key Largo woodrat ranges from 4.5 to 9.0 inches in length, with a tail of 4.7 to 9.0 in length.

Population Status and Distribution

The Key Largo woodrat is a federally endangered species that is endemic to Key Largo, Florida. This island population is separated by approximately 130 miles from the nearest population of woodrats on the mainland of Florida. Historically, the Key Largo woodrat occupied all of Key Largo, but today is restricted to approximately 2,000 acres in the northern one-third of the island.

Habitat

The Key Largo woodrat is a resident of tropical hardwood hammocks, a type of forest that occurs on upland areas in the Keys. These hammocks provide a shady, humid environment with less wind and temperature variation than more exposed areas. The soils are poorly developed and typically consist of a thin humus layer and litter lying on a limestone substrate. On Key Largo, tropical hardwood hammocks include a greater number of tropical plants than hammocks on the mainland. Many tree and shrub species are West Indian in origin and co-occur with a variety of vine species from temperate North America and the West Indies. The canopy within these forests typically reaches a height of 30 to 40 feet.

Threats

Habitat loss due to development and deforestation, and predation, particularly from feral house cats are the main factors limiting distribution of the Key Largo woodrat on the island. Despite protection of its remaining habitat, the Key Largo woodrat has continued to decline since its listing in 1984. The magnitude of this decline is not clear; a report from 1973 suggested that only 800 individuals may remain, and although the population was estimated at approximately 6,500 individuals in 1988, all subsequent estimates have suggested that < 500 individuals remain in the wild.

Behavior

Like other woodrat species, the Key Largo woodrat uses sticks, twigs, and other objects to build large stick nests in the hammock. These nests can reach 4 feet in height and 8 feet in diameter. Nests are typically occupied by a single woodrat, but individuals may maintain multiple nests throughout their home range. In addition to building natural nests on the forest floor, they also occupy cracks and crevices in the limestone and occasionally non-natural structures such as rock piles.

Conservation Efforts
Perhaps the most important effort to conserve the Key Largo woodrat was a cooperative land acquisition on north Key Largo. Today, most remaining habitat is public land comprised of Crocodile Lake National Wildlife Refuge and Dagny Johnson Key Largo Hammock Botanical State Park. Agency personnel and university researchers closely monitor the remaining Key Largo woodrats through live-trapping and nest surveys.

Links to more information:
https://www.fws.gov/verobeach/msrppdfs/keylargowoodrat.pdf

https://ecos.fws.gov/ecp0/profile/speciesProfile?spcode=A087

http://myfwc.com/wildlifehabitats/imperiled/profiles/mammals/key-largo-woodrat/