Tropical Hardwood Hammocks

Crucial habitat for the Key Largo Woodrat
THH

Tropical hardwood hammocks occur on the highest elevations of Key Largo. They are characterized by diverse woody plants, including numerous fruit-producing trees and shrubs, much of which commonly occur in the West Indies.  The soils in these forests are generally shallow and rich in accumulated organic matter on a limestone substrate.  These forests are extremely diverse, hosting over 140 species of trees and shrubs.  Some of these species include torchwood, gumbo-limbo, wild tamarind, wild lime, West Indian mahogany, pigeon plum, and wild coffee.

Historically, much of Key Largo was a dense hardwood hammock established on fossilized coral.  The harvest of West Indian mahogany and other native hardwoods was the first significant manmade impact to this habitat from the 1750's through the 1800’s.  Pineapple and citrus plantations, along with vegetable farming, also transformed and fragmented the hammock.  Residential development took hold in the 1930’s, creating more significant habitat fragmentation and loss.  Hurricanes and tropical storms have also impacted the hammock, though the native plants and wildlife are adapted to these sometimes violent but natural events. 

Seven of our eight listed species at Crocodile Lake National Wildlife Refuge are dependent on this special forest: Key Largo woodrat, Key Largo cotton mouse, Stock Island tree snail, Schaus’ swallowtail butterfly, Eastern indigo snake, Keys tree cactus, and the Florida semaphore cactus.  To compensate for the loss of habitat over the years, the USFWS as well as other organizations have put a considerable amount of effort into restoring tropical hardwood hammocks by removing and treating invasive exotic plants and planting native trees and shrubs.

Facts About Tropical Hardwood Hammocks

Seven of our eight listed species at Crocodile Lake National Wildlife Refuge are dependent on this forest.