Danielle Baviello
What exactly are coral reefs?
Coral reefs are rocky mounds and ridges formed
in the sea by marine organisms through the
accumulation and deposition of limestone, otherwise
known as calcium carbonate. Coral reefs are unique and
rich marine ecosystems.
-Hard Coral Colonies: living polyps
1) massive
2) branching
3) plate-like
Ecological Requirements of Coral
Reefs
 warm water (17-34°C)
 shallow coastal waters and bays
 sufficient sunlight to support photosynthesis
Where are coral reefs located?
- Pacific Ocean
- Atlantic Ocean
- Indian Ocean (including the Red Sea)
3 Widely Recognized Major Coral Reef Areas:
- Indo-Pacific Region
- Wider Caribbean
- Red Sea
Types of Coral Reefs
Atoll- a roughly circular oceanic reef system surrounding
a central lagoon
Fringing Reef - a reef system that grows fairly close or
directly from the shore, with an entirely shallow lagoon
or none at all
Barrier Reef - a reef system that is parallel to a shore and
is separated from it by a wide lagoon that contains some
depth in sections
How are coral reefs formed?
Coral reefs are formed by the accumulation of
limestone extracted from seawater. Small animals and
plants help form the mounds and ridges. The following
build the underlying framework:
-Reef-building Corals: Specialized kind of
animals.
-Coralline algae: Specialized kind of plants.
Species, Colors, and Classes
Two types of classes
 Vertebrates- Bony Fish
 Cartilaginous- cartilage fish like sharks and rays
Helpful fact: A majority of the fish dwelling in the coral
reef are bony fish
Fish Adaptations to the reef
 Body shape- Torpedo like shape for speed, laterally
compressed shape to make sharp turns
 Adaptive Coloration- Bright colors, odd patterns. This
is to hide from predators and attract mates. Also, some
fish have venomous spines or flesh to warn off
enemies.
 Feeding structure- Special digestive tracks to digest
plants/small fish. Some fish have sharp teeth to snip
off coral like the butterfly fish
Finding Nemo
 Anemones are coral reef animals that have stinging
tentacles to ward off other creatures.
 Anemones look like plants but are in fact sea animals.
 You may have herd of them from finding nemo.
 Clownfish (nemo) are fish that have adapted to
anemones. They are able to live in them with out
getting stung.
Herbivores
 Herbivores are fish that feed mainly on plants(feed on
small fish in some cases).
-Parrotfish- largest and most colorful herbivores
-Surgeonfishes
-Rabbitfish- closely allied with the Surgeon fish.
Elongated snout.
-Damesfish
Planktivores
 Planktivores are fish that feed on small
animal plankton.
- Open water plankton feeders
- Benthic Planktivores – hunt their pray
while remaining close to the reef.
- Nocturnal Planktivores- Hunt during the
night.
Benthic Carnivores
 Benthic Carnivors are fish that feed on invertebrate
animals and small fish that live on or near coral reef
habitats.
 These types of fish make up a majority of the fish
associated with living in the coral reef.
-Butterflyfish
-Triggerfish
-Trunkfish
Piscivores
 Piscivores are fish that pray on other fish. There are
three different hunting strategies these fish have;
pursuit, stalking and ambush
- Pursuing- fish that relay on speed to track down
their pray
- Stalking- watch and approach their pray before
they strike.
- Ambush- relay on their coloration to make them
seem invisible, and their stillness. Their pray won’t
see what's coming.
Coral Reef Plants
 Three main types
- Marine algae- essential to the survival of the coral reef
- Seagrasses- supports other forma of life. Provides a
habitat.
- Mangroves- Shoreline plants. Grow where there are
few waves. Located a far distance from hard corals.
Quick Facts about Coral Reefs
 The coral reefs are home to 25% of all marine life
 10% of the World’s coral reefs have been completely
destroyed
 70% of the reef in the Philippines is destroyed and
only 5% is in good condition
Coral Bleaching
 Colorful algae in the coral are expelled due to the
increase in temperature caused by global warming
 If the algae do not return the coral will die
 On warm days scientists are very concerned with this
phenomenon
Coral Mining
 Live coral is removed from the reefs and used in
construction as bricks or cement
 Coral is also taken from the reefs and sold as souvenirs
 They are also harvested for a live rock trade
Sedimentation and Pollution
 Sedimentation occurs when erosion caused by
construction, mining, logging, or farming flows into
the rivers and then into the ocean
 The sedimentation blocks light from reaching the
coral and can get caught in the reefs
 Pollution occurs when toxins are
dumped in the ocean or their runoff
reaches the ocean
 This can cause an overgrowth of
algae, blocking sunlight to the reef
Overfishing
 This can cause problems in the entire food
chain and cause problems beyond the reef
 Destructive fishing practices can eliminate
fish and the reeds themselves due to dynamite
fishing or muro-ami which means banging on
the reef with sticks so the fish will swim out
Why is this important?
 Coral reefs remove and recycle carbon dioxide
 They protect the land from harsh weather by
absorbing the impact from storms
 Very large biodiversity in the reefs and without them
many plants would die
 Lots of new things can be studied from reefs such as
ecosystems, biodiversity, biomes, and
interrelationships between organisms
References
http://www.coral-reef-info.com/
http://coralreef.noaa.gov/