On the Mainland, more than half of the original wetlands in the lower 48 states have been drained or converted to other uses. Research Ecologist Katherine Ewel of the USDA's Institute of Pacific Islands Forestry says literature shows some people were aware of the importance of wetlands in America well back into the 1800s, but it wasn't until the 1970s that something happened to make people sit up and take notice. What turned the tide, she says, was that the filling of prairie potholes for agricultural use severely depleted the numbers of migratory waterfowl. Since then, wetlands have continued to rise in the opinion stakes. For productivity, they are now rated alongside rain forests and coral reefs.
Wetlands act as flood control barriers for downstream areas.
And on a global scale, wetlands may even affect climate by serving as a sink for the greenhouse gas carbon dioxide. Wetlands are now protected by a slew of federal legislation and policy. Last year, Vice President Gore announced a new Clean Water Act initiative with the goal of a net gain of 100,000 acres of wetland a year in the United States starting in 2005. The James Campbell National Wildlife Refuge near Kahuku is one of Hawai'i's first manmade wetlands. Water levels are artificially controlled year-round to provide the best possible conditions for the birds.