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Coral reef communities within Florida waters are categorized as:
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Patch Reef Community
- Located in shallow water 10-20' (3-6 m)
- Outer edge ringed by sand
- Dominated by large star and brain coral colonies
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Patch reefs are located in shallow waters of 10-20 feet (3-6 m) in depth, within the Florida Reef Tract. The outer edge of each patch reef is surrounded by a halo of sand that extends out to adjacent seagrass beds. The width of this ring of sand is determined by the distance that herbivorous fish feel is within safe foraging range from the reef. Each patch reef differs in size, development, and species residing on them.
Arrow Crab
© Eugene Weber, California Academy of Sciences
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The patch reef originates with a coral larva settling out of the plankton onto a hard surface for attachment. It develops into a moderate-sized coral colony over time. Eventually the coral dies, perhaps from storm or predator damage, leaving behind the calcium carbonate skeleton upon which more coral larvae can settle. This continues for hundreds of years with the reef expanding upwards, towards the water's surface. As the reef reaches the surface, it will begin growing outward rather than upward.
Star Coral (Montastraea annularis) Polyps
© Mark Younger
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Large colonies of star and brain corals (Montastraea annularis, Siderastrea siderea, and Diploria spp.) form the base of many patch reefs, with smaller coral species settling on any exposed dead coral. Boring sponges, worms, and mollusks excavate through the coral skeleton, forming crevices that provide refuge for fish and invertebrates. Over time, the underlying foundation of the reef weakens resulting in the collapse of the structure.
Yellowtail Snapper
courtesy U.S. Geological Survey
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French Angelfish
© Eugene Weber, California Academy of Sciences
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Reef fish commonly found along the top of patch reefs include:
Parrotfish
© Luis Rocha
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Among the coral heads and branching corals are:
Fringed Filefish
© David Snyder
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Trumpetfish (Aulostomus maculatus) and filefish can be observed standing vertically among gorgonian branches. Larger predatory fish including grouper (Epinephelus spp.), snapper (Lutjanus spp.), bar jack (Caranx ruber), and great barracuda (Sphyraena barracuda) search for prey in the water above the reef formation.
Squirrelfish
© Eugene Weber, California Academy of Sciences
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Pufferfish, squirrelfish, cardinalfish, and green morays (Gymnothorax funebris) take cover in deep caves along with spiny lobsters. Herbivorous fishes often seek refuge on the patch reefs during daylight hours, venturing out at night to feed in the nearby seagrasses.
Blueheads
© Steve Turek
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