Welcome to Lignumvitae Key Aquatic Preserve (pronounced "LIG-nuhm-VY-tee"), a 6,700-acre protected area adjacent to Islamorada in the Upper Florida Keys. The aquatic preserve spans a unique transitional zone between Florida Bay and the Atlantic Ocean. This vital productive area includes seagrass flats, mangroves and hardbottom communities, which support a wondrous diversity of life.
Lignumvitae Key Aquatic Preserve was designated in 1969 by the Florida Legislature. Today, Lignumvitae Key is one of 42 Florida aquatic preserves that have been set aside to ensure these exceptional underwater ecosystems are safeguarded for generations to come. These protected areas are managed by the Florida Department of Environmental Protection through the Office of Resilience and Coastal Protection. The Florida Park Service co-manages the aquatic preserve as part of the Lignumvitae Key Botanical State Park, which overlaps most of the aquatic preserve. The aquatic preserve spans a unique transitional zone between Florida Bay and the Atlantic Ocean.
Lignumvitae Key Aquatic Preserve encompasses 6,700 acres of seagrass meadows, deep water channels, hard-bottom communities and mangrove wetlands.
Rare wading birds often can be observed foraging in the shallow waters of the tropical lagoon and among the mangroves.
Activities within the aquatic preserve include boating, snorkeling, commercial fishing, marine life collecting, charter sport fishing and recreational fishing for finfish and lobster.
The tropical hardwood hammock that thrives on Lignumvitae Key is one of the few remaining virgin forests of its type in Florida's Upper Keys.
In 1919, William J. Matheson, a wealthy Miami chemist, bought this tiny island and built a caretaker's home with a windmill for electricity and a cistern for rainwater. This building is now the visitor center for the park, which is accessible only by boat.
An underwater seagrass bed community.
A topside view of Lignumvitae Key Aquatic Preserve waters.
Lignumvitae Key Aquatic Preserve is located in the upper half of the Florida Keys in Monroe County. The aquatic preserve includes 6,700 acres of submerged lands lying north and south of U.S. Highway 1 (Overseas Highway), between Upper Matecumbe Key (Islamorada) and Lower Matecumbe Key. It overlaps much of Lignumvitae Key Botanical Botanical Park.
No archaeological resources are listed within the aquatic preserve, however several historical sites are nearby.
On Lignumvitae Key, the Matheson House, a caretaker's home built in 1919, serves as the visitor center for the Lignumvitae Key Botanical State Park and offers visitors a glimpse of how island people lived during a time when most of their needs were met by the land and sea around them.
In 18 feet of water south of Indian Key lies the San Pedro wreck that sank in 1733. Established as the San Pedro Underwater Archaeological Site in 1989, the wreck exists as a part of Florida's rich maritime history.
Indian Key lies south of the aquatic preserve's boundary lines - a small island that has been occupied by various cultures from prehistoric times. In the 1800s, it was a prominent trading village, but it has not been inhabited since the 1930s and is now owned by the state of Florida.
October 3, 2023 - 11:11am
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The Florida Department of Environmental Protection is the state’s lead agency for environmental management and stewardship – protecting our air, water and land. The vision of the Florida Department of Environmental Protection is to create strong community partnerships, safeguard Florida’s natural resources and enhance its ecosystems.