OCS2008 Coral Reefs Study Guide

Flashcards based on the key concepts from the OCS2008 Coral Reefs Study Guide.

Cnidaria

The phylum that corals belong to.

Anthozoa

The class that corals are classified under.

Hermatypic corals

Reef building corals.

Colonial organisms

Organisms made up of multiple individuals, such as polyps in corals.

Zooxanthellae

Symbiotic algae that live in coral tissues and provide nutrition through photosynthesis.

Nutrition contribution of zooxanthellae to corals

Approximately 71% of their nutrition comes from zooxanthellae.

Predation on zooplankton

Accounts for 17% of nutritional intake for corals.

Dissolved organic matter

Provides 12% of the nutrition for corals.

Coralline algae

Algae that cement loose rubble and sediments together, holding reefs together.

Parrotfishes

Biogenic source of sediments on and around coral reefs.

Temperature limits for coral distribution

Corals are limited to ~25˚N - 25˚S due to temperature.

Depth limit for corals

Corals are typically found at depths of 25 – 50 m due to light requirements for zooxanthellae.

Bleaching

A stress response in corals that leads to the expulsion of zooxanthellae.

Eutrophication

A process that stimulates algal growth, which can smother corals and is detrimental to their health.

Types of coral reefs

The three main types are fringing reefs, barrier reefs, and atolls.

Atoll formation process

Begins with a volcanic island > fringing reef > barrier reef > atoll.

Coldwater corals

Corals that occur in deeper waters, lack zooxanthellae, and rely on predation for energy.