According to new studies, the mangroves' habitat provides important shelter to small fish and other wildlife that comprise a coral reef's elaborate living network.

Mangrove forests, which can encompass dozens of different species of plants, are deeply rooted in the sand and mud that run parallel to the edge of a body of water. They are found in the tropics and sub-tropics, primarily in saltwater, although some plants can also adapt to freshwater environments.

These plant communities need protection from constant surf, which can erode the shore and make it difficult for new plants to take root. In some cases large coral reef systems, such as the Great Barrier Reef in the waters off of Australia, provide shelter for mangroves by protecting the plants from being battered by waves.

Mangroves host a variety of wildlife both above and below the waterline. Birds, small animals and insects utilize trees and larger plants while fish, snakes and other aquatic creatures use the maze of roots and plant life for food and shelter.

In addition to hosting several different types of animal life, mangroves also play a key role in preventing erosion and filtering storm runoff or other water pollution as they are anchored directly to the shoreline.

A recent study conducted by marine biologists and other scientists published in the journal Nature, found that mangroves are critical breeding grounds for coral reef fish.

Researchers compared the populations of over 100 fish in two habitats: coral reefs both close to and isolated from mangrove forests.

The scientists found that mangroves were shown to harbor small fish from predators until they were big enough to swim out to the reef, leading to a larger and healthier community of fish for the coral reef.

"They survive well in the mangroves until they are a bit larger," Peter Mumby, a marine biologist at the University of Exeter told National Geographic News of the study. "But at some point they need to move to the reef. We are not sure why they move to the reef, but [we] suspect it's a good place to reproduce."

The Australian government estimates that some 75 percent of fish caught commercially spend some time in the mangroves or rely on the food chain that exists in the plant systems.

Scientists believe that new conservation efforts will be necessary to protect and foster mangrove habitats in the future.

The coastal forests are often cleared to make way for shrimp farms or other reasons, particularly in developing countries where a centralized regulatory government agency for environmental concerns may not exist or have the resources to devote to mangrove protection.

Ivan Valiela, a marine biologist with Boston University's Marine Biological Laboratory, told National Geographic that his team's research indicates that mangroves are being destroyed at more than twice the rate of tropical rainforests.

"Maintenance of these important environments therefore has to be done from a wider perspective," Valiela told the magazine. "This whole set of concepts bears on the issue of setting up coastal reserves, national parks, maintaining commercial stocks, and a host of other management issues."

-- By Maureen Hoch, Online NewsHour