Ecology of South Florida (EVR 3013) LECTURE 25
MARINE COMMUNITIES II
CORAL REEFS
FROM: BALLAD OF THE GREEN TURTLE
Where the green turtle comes in the dark of the moon
To this lonely spit of sand
And crawls from the waters--amongst the quiet dunes
And buries her eggs in the sand
The hatchlings are bound to the call of the sea
According to nature's plans
The scurry thru danger and into the waves
A cycle older than man
Will McLean (1980) [in Jones and O'Sullivan 1995]
HANDOUTS: 1. Species List for coral reefs
I. DEFINITIONS
A. Reefs
Biologically-produced, geomorphic structures often made of calcium carbonate, reef-building organisms secrete calcium-carbonate as they grow.
B. Several kinds of reefs
- worm-reefs--Phragmatopoma lapidosa
- mollusk reefs
- Ivory coral--Oculina varicosa
- bryazoan
- artificial
- coral, produce by skeleton of corals and shell fragments and calcareous algae
C. Corals
- Free-swimming medusae and sessile polyp stage
- Zooxanththellae - up to one million/cm2 of coral surface, provide much of the color of corals. Corals provide the algae a constant physical environment (CO2, N and P wastes). Corals gain O2 and wastes are removed. Up to 90% of the algal photosynthate may be transmitted to the coral
II. PHYSICAL FEATURES
A. Distribution
Florida Keys, reef corals occur as far north as Jupiter but at present are not building reefs north of Cape Florida, Gulf Stream brings warm, nutrient-poor water vital for reefs
B. Physical Attributes
- two types--Bank and patch
- limited to 30 m in Keys
III. PLANTS
A. Composition
Algae common, vascular plants rare.
B. Plant Species List for Coral Reefs
Algae
|
|---|
| Umbrella Algae | | Acetabularia crenulata |
| Green Fleece | | Coduium decorticum |
| Disk algae | | Halimeda incrassata |
| Mermaid's Shaving Brush | | Penicillus captitatus |
| Sargassum | | Sargassum natans |
| Sea lettuce | | Ulva lactuca |
IV. ANIMALS
A. Diversity
Extremely high
B. Animal species list for Coral Reefs
1. Birds |
|---|
| Osprey | | Pandion haliaetusSSC |
| Royal tern | | Stern maxima |
| Double-crested cormorant | | Phalacrocorax auritus |
| Brown pelican | | Pelicanus occidentalisSSC |
2. Mammals |
|---|
| Florida manatee | | Trichechus manatusT |
| Bottle-nose dolphin | | Tursiops truncatus |
3. Reptiles |
|---|
| Green sea turtle | | Chelonia mydasT |
| Loggerhead turtle | | Caretta carettaT |
4. Fish |
|---|
| Mangrove snapper | | Lutjanus griseus |
| Tarpon | | Megalops atlanticus |
| Mullet | | Mugil cephalus |
| Great Barracuda | | Sphyraena barracuda |
| Atlantic Sailfish | | Istiophorus platypterus |
5. Sponges |
|---|
| Loggerhead sponge | | Spheciospongia vesparium |
| Vase sponge | | Icinia campana |
6. Corals |
|---|
| Common sea fan | | Gorgonia ventalina |
| Elkhorn coral | | Acropora palmata |
| Finger coral | | Porites porites |
| Grooved brain coral | | Diploria labyreinthiformis |
| Staghorn coral | | Acropora cervicornis |
| Star coral | | Montastrea annularis |
| Starlet coral | | Siderastrea radians |
7. Jellyfish |
|---|
| Portuguese man-of-war | | Physalia physalia |
8. Gastropods |
|---|
| Horse conch | | Leuroploca gigantea | [state shell] |
| Queen conch | | Strombus gigasSSC |
9. Crustaceans |
|---|
| Spiny lobster | | Panulirus argus |
| Pink shrimp | | Peneaus duorarum |
| White shrimp | | Penaeus setiferus |
10. Sea urchins |
|---|
| Long-spined sea urchin | | Diadema antillarum |
For superscript by species name: C = commercially exploited, SSC = species of special concern, T = threatened. Florida Game and Freshwater Fish Commission listings. EX = exotic.
V. BIOTIC RELATIONSHIPS
A. Endemics
B. Exotics
C. Diversity
Coral reefs are renowned for diversity
| Type of Organism | | Number of Species |
|---|
| Algae | | 60 |
| Sponges | | 120 |
| Octocorals | | 42 |
| Stony corals | | 63 |
| Crustaceans | | 500 |
| Polychaetes | | 450 |
| Mollusks | | 1200 |
| Echinoderms | | 75 |
| Fish | | 450 |
| Birds | | 40 |
VI. ECOLOGICAL PROCESSES
A. Productivity
(g C m-2 yr-1)
B. Succession
VII. HUMAN EFFECTS
A. Pre-Colombian
Harvested fish, mollusks and sea turtles
B. 18th and 19th century
- Spanish wrecks
- 1897 Sponge industry employed 1400 people and was worth $284,640
- Dredging
C. 20th century
- 1912 Railroad was completed to Key West, destroyed in 1935 hurricane
- Dredging
- Overfishing
- Anchor scars
- Lobster overharvest
- Red and black band coral diseases
- Importance - Molasses Reef generates $400 million per year (meals, lodging, boat rentals equipment rentals) valued - 267 sq. ft.
Back to start, Back to lecture 20, 21, 22, 23, 24, On to lecture 26, 27
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