Everglades National Park covers 1.4 million acres,about a seventh of the Everglades.It is the largest continuous stand of sawgrass prairie and the most significant breeding grounds for tropical wading birds in North America.It is the largest mangrove ecosystem in the western hemisphere. South Florida gets a lot of rain,60 inches a year.Yet the region has water shortages due to over develoment.The Everglades' natural ability to store water has been interrupted by canals and levees.Because the waterway is channeled,the Everglades losses 1.7 billion gallons per day of fresh water into the Alantic Ocean and the Gulf of Mexico at such a fast pace nature cannot use it appropiately. Fresh water flowing out of the Evergaldes mixes with salt water to form estuaries,home to at least 70% of harvested fish and shellfish in South Florida.The cemicals and nutrients which pollute the Everglades destroy an algae called periphyton.these algae are a key link in the food chain.In dry season,this algae gives moisture to small organisms so they can survive untill it rains. Phosphorus promotes the growth of marsh plants such as cattails,which crowd out other plants.Their rampant growth crowds out other native plants.When cattails die,they use up oxgen to decompose,leaving fish to die. Lightning starts fires in the Everglades.Until 1958 the National Park Service suppressed all fires.A study showed tat fire was necessary to maintain biological diversity.The Everglades became the site of the first prescribe fire in a National Park.How does fire help the Evergaldes?Fire removes decaying vegetation and allows for regrowth.That new growth,plus nutrients released from the burn,increases food and habitat for wildlife. Everglades Facts by National Wildlife Federation Web Site.