Honors Marine Biology

Module 11

Coral Reefs

Class Challenge

Share your most unique thing about yourself.

Estuary Presentations

Coral Reefs are home to an amazing assortment of organisms and are truly the underwater equivalent of a diverse rain forest.

Coral reef communities are found in the tropical climates of the world because reef-building corals need warm temperature in order to survive.

They are found between the Tropic of Cancer and Tropic of Capricorn latitudes.

Coral Reefs

This “band” around the earth receives a much larger portion of sunlight throughout the year than the rest of the world and has overall warmer climates.

Upwelling along the Western Coastlines

Figure 11.1

Central America

South America

Africa

The Coriolis Effect

Causes ocean currents to spiral clockwise in the Northern Hemisphere and counterclockwise in the Southern Hemisphere.

This effect results in the presence of cooler water off these western coasts, therefore it does not support the growth of corals.

Back in Module 4Hard surfaces and Shallow water in which light can penetrate.

Also……

You learned that these types of corals cannot grow well without the presence of tiny algae called zooxanthellae.

Corals need clear water to allow for superior light penetration.

Coral Reefs consist of two major components:

1. Reef Builders are organisms that actually produce the reef structure. These are the tiny animals called corals. They produce calcium Carbonate (limestone) which is their “armor” around their bodies.

2. Reef inhabitants

Taxonomy of Coral

Page 264 Figure 11.4

Phylum Cnidaria

Class Anthozoa

1. Subclass Alcyonaria (soft corals, sea fans and sea pens)

2. Subclass Zoantharia (sea anemones, corals)

See Figure 11.6 (pg. 265) Diagram of

• Each corallite has a series of sharp edges radiating from the center of the corallite cup called Septa.

• Around its perimeter and pointed Columella extending upwards from the floor of a corallite cup.

Coral Growth FormationsFigure 11.7

• Corals have a large variety of growth forms based upon their budding patterns:

• Boulder Coral (Encrusting) : bud mostly sideways or uniformly upward, covering existing hard substrates.

• Branching coral: are mainly made up of vertically budded polyps.

• Foliacious Coral: use a combination of both horizontal and vertical directions.

The Coral Spawn

http://youtu.be/pnDJvhgPn8o

Blue Planet: Coral Sea: GBR - Coral Spawning

http://youtu.be/wsaZ8-I7akg

Types of Reefs

1. Fringing Reef: A type of coral reef that forms as a border along the coast.

Fringing Reef

Barrier Reef

2. Barrier Reef: A type of coral reef that occurs at a distance from the coast.

Barrier Reef

Atoll Reef

3. Atoll: A ring of coral reef with a steep outer slopes, enclosing a shallow lagoon.

Atoll Reef

formation

Lab: Diagram of Coral

Homework

1. Module 11: Read pages 269 to 280.

2. OYO questions : 11. 7 – 11. 15

3. Study Guide: define: d-e; 14 – 26

4. Quiz on Corals and Coral polyps

5. Class challenge