Image credit: Shek Graham/Flickr
Around the world, marine environments are threatened by overfishing, warming waters, ocean acidification, and coastal development. The diminished biomass and diversity that results leaves ecosystems vulnerable to disease and natural disasters and jeopardizes the economies of the communities that rely on marine resources.
While in many places the situation is getting worse, encouraging new research supports the power and benefit of conservation measures.
Rebounds in the Great Barrier Reef
In Australia, efforts to preserve the biomass of the Great Barrier Reef have led officials to ban fishing across 32 percent of the area. Since they were established, fish densities in these "no-take zones" have more than doubled. This increase has spread across the reef, with densities growing outside of the preserves as well.
Dr Laurence McCook, lead author of a new survey of preserves along the Great Barrier Reef, explained:
Critically, the reserves...benefit overall ecosystem health and resilience...outbreaks of coral-eating, crown-of-thorns starfish are less frequent on no-take reefs, which consequently have a higher abundance of healthy corals after outbreaks.
The net benefit, the survey suggests, extends to the fishing and tourism industries as well as the environment. "The Great Barrier Reef," McCook said, "generates far more economic benefit to Australia than the cost of protecting it."
Reversing Habitat Damage in the Gulf of California
Overfishing in the Gulf of California, an area Jacques Cousteau called the "world's aquarium," has had a serious impact on the biomass. Specifically, a fishing practice called "hookah" diving—in which fisherman use a makeshift hose to breathe oxygen threw as they spear or gather large amounts of fish—has devestated the balance of the food chain in these ecosystems.
Octavio Aburto-Oropeza, a researcher at the Scripps Institution of Oceanography at UC San Diego, explained:
In these studies, whether reefs or mangroves, we are trying to show that the destruction on the coast and overexploitation in other areas are diminishing the biomass (the amount of organisms in an ecosystem) in several areas...with lower biomass, the large predators, the keys to a robust marine ecosystem, are missing and that causes disruption down the marine food web.
The good news is that small conservation efforts have already yielded big results. One thing all of these efforts have in common is a dramatic reduction or complete elimination of fishing.
Read more about marine preserves:
Coral Can Recover from Climate Change Damage... In Marine Reserves
6 Steps to Saving the World's Coral Reefs
Bush Plan for Marine Preserve Threatened By His Own Vice President