Coral Reefs and the Papahānaumokuākea Marine National Monument

What do you know about these topics? What are the major characteristics of a coral reef ecosystem? Where are coral reefs located? Are there any coral reefs in the United States? What value, if any, are coral reefs to humans? Please answer these pre-assessment questions on your worksheet

You’ll learn more information on these topics throughout this slide show!

Major characteristics of reefs complex, biologically diverse ecosystems home to more kinds of life than any other marine environment, rivaling even the tropical rainforests on land

More Reef Characteristics The delicate marine environment of the reef itself relies upon the interaction of many different forms of life: hard and soft corals, algae, fish, sponges, crustaceans, worms, turtles, dolphins and other sea life.

Corals – the basis of the reef Composed of thin plates or layers of calcium carbonate secreted over thousands of years by billions of tiny, soft- bodied animals called coral polyps. The reef is constantly growing new colonies of polyps on top of the skeletons of older ones. Corals typically grow only one-half inch per year.

A single coral polyp is a tiny animal

Check out a coral polyp from different perspectives! Up close! In cross section!

Corals are consumers! They may look like plants or tiny flowers but…. Corals use their tentacles to capture or collect plankton from the surrounding water In places where there is limited plankton, corals have another way of getting fed…..

Corals often contain a symbiotic algae in their tissues called zooxanthellae

This symbiosis benefits both the coral and the algae Coral provides the algae with a protected environment and the compounds necessary for photosynthesis: carbon dioxide, produced by coral respiration, and inorganic nutrients such as nitrates, and phosphates, which are metabolic waste products of the coral. In return, the algae produce oxygen and help the coral to remove wastes. They also supply the coral with organic products of photosynthesis. These compounds, including glucose, glycerol, and amino acids, are utilized by the coral as building blocks in the manufacture of proteins, fats, and carbohydrates, as well as the synthesis of calcium carbonate (CaCO3) that forms the hard part of the reef

Zooxanthellae often are critical elements in the continuing health of reef- building corals. As much as 90% of the organic material they manufacture photosynthetically is transferred to the host coral tissue!

There are other organisms that build coral reefs Algae that produce a hard exterior called coralline algae Sponges Other invertebrates like mollusks

Healthy reefs in Hawaii are often algae-dominated

Given what you’ve learned about coral reefs….. Where in the world do you think reefs exist? What kind of environmental conditions do they need to survive? Take a few minutes to discuss your ideas with a classmate sitting near you!

Abiotic (environmental) factors are also important in defining coral reefs Reefs need: Sunlight Clear water so that the sunlight can penetrate Temperatures in a range near 18°C

They are affected by currents and wave action

Coral Reefs are located near the equator

We do have reefs in the U.S. Red dots represent the reef study sites of the Millennium Ecosystem Study

The Papahānaumokuākea Marine National Monument, northwest of the main Hawaiian Islands, is one the largest marine preserves in the world and contains extensive coral reefs

The Papahānaumokuākea Marine National Monument Created by President Bush in 2006 Encompasses 137,797 square miles of the Pacific Ocean (105,564 square nautical miles) - an area larger than all the country's national parks combined.

The Monument is part of your natural heritage! The monument benefits from the most stringent environmental protection and ongoing scientific research The extensive coral reefs found in Papahānaumokuākea - truly the rainforests of the sea - are home to over 7,000 marine species! It is a place of great cultural significance to the Hawaiian people

What value, if any, are coral reefs to humans? Reefs protect coastal areas from storm surge by absorbing the impact of wave and wind action Coral reefs are also valuable for commercial and sport fishing, tourism and recreational opportunities for diving, boating, and photography They have value as a natural wilderness that provides habitat for numerous species- some of them endangered. Coral reefs also filter water and trap sediments

Coral reefs are storehouses of genetic resources with vast medicinal potential – currently being researched are: a cancer therapy made from algae a painkiller taken from the venom in cone snails antiviral drugs Ara-A and AZT and the anticancer agent Ara- C, developed from extracts of sponges

Are there other reasons you can think of to value coral reefs? Why would Hawaiians or other island cultures hold them sacred? Discuss these questions with your classmates!

Acknowledgements Contributors to the NOAA CoRIS web site including: R.D. Barnes (1987), R.S.K. Barnes and Hughes (1999), Lalli and Parsons (1995), Levinton (1995) and Sumich (1996) David A. Krupp, online lecture notes Andrew W. Bruckner, “Life Saving Products from Coral Reefs” Photo credits: James Watt, Daniel Suthers, Andy Collins, John Reed and Keoki Stender