John Pennekamp Coral Reefs

Pennekamp Coral Reefs

What makes the coral reefs of the Florida Keys so special? Well, for starters, the Florida Keys Reef Tract is the only living coral barrier reef in North America, and is the 3rd largest coral barrier reef in the world (after the Great Barrier Reef in Australia and the Meso-American Reef in Belieze). The reef runs roughly 221 miles down the south-eastern coast of Florida, paralleling the Florida Keys from Key Biscayne off Miami down to the Dry Tortugas, 70 miles west of Key West, from 1 mile to 8 miles offshore. The proximity of the reef (just a half-hour boat ride from land); the warm, clear water from the Gulf Stream just offshore; and the fantastic richness of life found here makes the reefs of the Florida Keys one of the most uniquely beautiful and accessible wild areas in the country.

CORAL REEFS are special because of the community of organisms that build the reef, the HARD and SOFT CORALS. Corals are animals in the Phylum Cnidaria (the group of animals that includes jellyfish and sea anemeones), Class Anthozoa. Corals are found in a variety of forms, from the hard branches of Elkhorn Coral to the soft leaf-like structures of Sea Fans. Corals can generally be divided into SOFT CORALS (Subclass Octocorallia), which have a soft, flexible skeleton of protein (similar to what makes up human fingernails or hair); and HARD CORALS (Subclass Zoantharia, Order Scleractinia), which form a hard exoskeleton of secreted calcium carbonate (limestone). Since the hard corals have a skeleton that is literally rock, it is their growth that really forms the structure of the reef. Each coral head is really a colony of thousands of individual animals called CORAL POLYPS, which look something like upside-down jellyfish.

As the coral colony grows and new polyps form through the division of old polyps, each individual coral polyp will lift itself up off the floor of its old cup and will secrete a new calcium carbonate floor underneath it, causing the entire coral head to expand up and outwards. A cross-section of a coral head clearly shows the successive layers formed by each polyp’s growth and expansion outwards. As the polyps move outwards, they leave behind them a dead limestone skeleton, so the only living part on any coral head is the outer 2-3 millimeters. Most hard corals in the Keys grow at a rate of 1/4 - 1/2 inch a year, and it ends up taking about 50 years for a brain coral to grow to the size of a basketball. Branching corals (such as the hard coral Acropora cervicornis, Staghorn Coral) grow somewhat faster, up to 1 1/2 inches a year, but at the price of being much more brittle and prone to damage from storms, ship groundings, or careless divers. Since the soft, jellyfish-like outer layer is the only living part of any coral head, a diver or snorkeler can easily damage or kill a coral merely by touching it! This is the reason behind the Sanctuary Preservation Areas, better known as "No Touch, No Take" Zones.

The reefs of the Florida Keys usually span several of these categories. The only reef type not found in the Keys is the atoll! True fringing reefs are rare in the Keys, and are found almost exclusively in the Dry Tortugas, which means that you must take a boat ride if you wish to see the reef. However, the outer reef tract is much closer to shore than many barrier reefs, becoming almost a "fringing barrier reef"; the outer patch reefs are often closer to bank reefs, with the deep water surrounding them, whereas several of the inshore patch reefs are fantastic miniature models of a barrier reef, complete with the protected lagoon area behind them. Although this tends to drive coral researchers to distraction, snorkelers and divers greatly benefit; the Keys provide some of the most unique snorkeling and diving opportunities in the world!

Location:
Mile Marker 102.5
Overseas Highway
Key Largo, FL
(800) 326-3521
website: www.pennekamppark.com

See:
• Jules Undersea Lodge
• John Pennekamp Coral Reef State Park
• Pennekamp Reef Information
• Diving Pennekamp Reefs
• Reef Animals & Fish
• Dive and Snorkeling
• Sailing