PANAMA CITY, Fla. — Scientists and environmentalists worry that 3,500 miles of Gulf of Mexico coastline from Mexico's Yucatan Peninsula to Cape Sable in Florida's Everglades National Park, ringed with rich, diverse habitats where many imperiled birds and animals breed and feed, would be at risk if the oil spill reaches them.
"It has the potential of being a disaster ecologically," said John Bente, the lead biologist for 13 coastal state parks in Florida. "It's just frightening."
In his office at St. Andrews Bay State Park in western Florida's Panhandle on Wednesday, Bente studied a map and wondered if the looming slick would make its way into a fragile estuary that supports some 3,600 species, from endangered beach mice to redfish.
Linked to the Gulf of Mexico by two passes around Shell Island, St. Andrews Bay opens just inland from the hilly dunes and sugar soft sand of the coast. Fed by creeks and bayous, the bay boasts the lushest seagrass beds in the Florida Panhandle, as well as salt marshes, tidal flats and oyster mounds.
Elsewhere, the fear is the same. Kemp's Ridley sea turtles lay eggs on the beaches of Texas and Mexico. Least terns nest on the beaches around Biloxi, Miss., and snowy plovers along Panama City Beach. Manatees munch seagrass from Florida Bay to Tampa Bay.
"All of these coastal areas, the salt marshes and the sea grass beds and the oyster bars, all support what we call foundation species," said Felicia Coleman, the director of Florida State University's Coastal and Marine Lab in Tallahassee, Fla. "It's the glue that keeps the coastal environment chugging along."
The open gulf also teams with life. Five species of rare sea turtles swim its vast waters, which also teems with whales, dolphin, shark and an array of species that wind up on hooks or in nets, from red snapper to bluefin tuna to pink shrimp.
More important, it's a vital seasonal spawning area for those same species, along with grouper, lobster, blue crabs and others. They move to the deep Gulf to set their tiny offspring adrift in the swirling currents that help restock coral reefs, bays and marshes from the Yucatan to the Florida Keys.
For now, with the Coast Guard and British Petroleum struggling to cap an undersea well gushing an estimated 210,000 gallons of oil daily, it's difficult to predict how widespread the damage to the Gulf might be.
James Fourqurean, a marine biologist at Florida International University in Miami, views the oil slick like a hurricane with a cone of danger covering the entire Gulf. For now, no one can predict where it will go, and not everyplace will be hit.
So far, the visible victims have been limited — blackened salt marshes on the Louisiana Delta and one oil-slimed Northern gannet, a seabird found in the slick. Some three-dozen dead turtles also have been found along Gulf beaches in recent weeks, but oil hasn't showed up in necropsies, and federal fisheries managers are investigating whether shrimpers are to blame.
However, Audubon reported Wednesday that oil had begun hitting the Chandeleur Islands, south of Gulfport, Miss., which are a breeding spot for sandwich and royal terns and the brown pelican.
"This is another sad milestone in a disaster unfolding in slow motion," said Audubon President Frank Gill in a press release. "This massive oil slick is churning around in the Gulf and emulsifying into a thick, deadly 'mousse' that will extinguish life and destroy habitats."
Biologists suspect that there already may be massive but unseen impacts that could have broad ripple effects. Slicks of oil are lethal to most of those drifting eggs and fish larvae, said Tamara Frank, an associate research professor at a Florida Atlantic University branch campus in Fort Pierce, Fla.
"That is going to be the problem," she said.
Plankton aren't strong enough to swim away, and if the tiny creatures aren't instantly poisoned, they'll soon suffocate, she said. "Anything that uses gills, like crustaceans and fish, is going to have problems. They way gills work, they have a lot of surface area. They're really frilly, and the oil is going to clump and stick on them."
Even before the massive spill, pollution and other environmental problems have plagued the Gulf of Mexico.
Pesticides, fertilizers and other chemicals pouring out of the Mississippi River have created a massive, oxygen-poor undersea "dead zone'' every year that, so far at least, dwarfs the spill.
Fish-killing algae red tides periodically hit the Gulf Coast, particularly around Southwest
Florida. Commercial and sports fishing have hammered some species so hard — notably popular fare such as red snapper and grouper — that federal fisheries managers have issued a series of escalating restrictions.
Even a Gulf in decline has managed to remain vibrant, particularly in sections, however, at east for now.
(Morgan and Goodman report for The Miami Herald. Donna Melton of the Biloxi Sun Herald contributed to this report.)
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