See Corals for information about corals in Hawai'i.

When snorkelling or diving you should not touch, walk on, stand or break live corals. Corals are living organisms and any contact with your body or fins can kill or damage them. Corals only have a very thin layer of live tissue on top of their skeletons- if you stand, hold onto or kick corals you may damage decades of coral growth. Hard corals are essential to the coral reef ecosystem, providing food and shelter to many organisms.

Do not remove anything from the reef. Everything has a purpose in the reef ecosystem and if you remove something you may be disturbing the natural balance of the ecosystem. Even an empty shell can provide an animal with a home or help to replenish beaches. Taking live coral or rock with attached marine life is illegal in Hawai'i. Do not touch, pick up or hold the organisms on the reef- you can injure them and yourself when doing so.

Fish feeding upsets the natural balance and can be harmful to fish. If fish eat introduced human food they will not eat their normal diet. If they don’t graze on algae it may become overgrown and compete with corals. Fish feeding changes the behavior of reef fish, causing them to be more aggressive, frightening other swimmers. Fish can even get sick and die from eating human food.

If you are using sunscreen use an environmentally friendly brand and put it on at least 15 minutes before you enter the water. Make sure it is waterproof- the oil and chemicals left in the water from sunscreen can create a slick on the surface that reduces gas exchange and can be harmful to reef animals.

Dispose of your trash properly! Plastics in the water can damage and kill marine life through entanglement and ingestion. Plastic bags can wrap around or cover corals, causing them to suffocate and die. Sea turtles and sea birds can mistake plastic debris for food. Once ingested plastics can block digestive systems and release chemicals. A plastic bag can last 1000 years in the ocean, an aluminum can 500 years and a plastic bottle 450 years. Participate in local beach clean-ups or organize them.

Photographs: Robert Shallenberger and Andrew Walsh.