Hodgson said that in developing countries like the Philippines and Indonesia homes of some of the most biologically diverse reefs ecotourism can help people strike a better balance with the environment while continuing to make a living. On most of the reefs surveyed by Reef Check, important species that should be there lobster, grouper, sea cucumbers are missing, Hodgson said. Without such algae-eating creatures, algae becomes so dominant it overwhelms the ecosystem. The opposite problem hit many reefs in 1998, an El Nino year that saw the warmest ocean temperatures on record. The warmer conditions killed the algae the coral needs to survive, bleaching the reefs white.
Coral structures are colonies of animals, and they get their color from algae.
In bleaching, the animals expel most of the algae. Usually, the remaining algae can repopulate the coral later on and restore its color. An otherwise healthy reef can bounce back from a bleaching. Reef problems triggered by climate changes are continuing. In early April, Fiji began seeing major coral bleaching, Hodgson said.