Dozens of species of land and sea animals, along with the fisherman who live off the bounty of the Gulf of Mexico and coastal wetlands off Louisiana, are under threat by a massive oil slick hitting the southeastern US shore.
At the epicenter of what could be the worst manmade ecological disaster to ever hit the United States -- the spot in the Gulf where 5,000 barrels of oil are spewing each day from a leaking sunken oil rig -- bottlenose dolphins and sperm whales are especially threatened, environmentalists to said.
Closer to shore, Louisiana's shrimp industry, which locals say is the source of most of the shrimp that goes onto dinner tables around the world, was looking at a doomsday scenario.
Fisheries officials opened the shrimp season Thursday at noon, at least a week before it was due to start, Margaret Curole, a former commercial shrimper and now a self-described fisheries activist, told AFP.
"They called the emergency opening of the season so the guys could try to go out and get a few shrimp before the oil gets here," she said.
On Friday, Louisiana Governor Bobby Jindal announced that many offshore shrimp fisheries and oyster beds had been shut and those closer to land would only remain open for a few more hours as the slick closed in.
The vast majority of shrimp fished in the Gulf are spawned in estuaries running from the mouth of the Mississippi River to the Atchafalaya basin further west, Curole said.
As the slick headed toward those fertile estuaries, it would pass through Gulf waters near the shore where bottlenose dolphins like to cluster.
"That incoming oil slick can devastate bottlenose dolphin populations, some of which only have a few dozen members," Natural Resources Defense Council senior policy analyst and marine animal expert Michael Jasny told AFP.
Sperm whales had probably already felt the impact of the spill, he said.
Mother sperm whales and their young use the Gulf waters located to the south and east of the Mississippi delta as their nursery. That area is already "under direct assault from the spill," said Jasny.
Oil can kill animals by coating their skins and suffocating them, or by toxic inhalation.
But it also acts as an invisible killer that Doug Rader, chief ocean scientist at the Environmental Defense Fund, said could wipe out generations to come of fish in the Gulf of Mexico.
"The top of the sea is like an interstate highway for larvae that move with the current to spawning zones far afield," Rader told AFP.
"The oil is at its most toxic, and the animals are at their most sensitive, in that surface zone, and that threatens to wipe out a whole generation of snappers and groupers and other fish," he said.
The slick was slithering up to the spawning grounds of Louisiana's local redfish, which attract recreational fishermen for tournaments that form part of the backbone of the state's economy.
"Our entire economy could be wiped out, whether it's the tourism dollar from guys coming in to fish, or the millions of pounds of shrimp that come in to port at Grand Isle every year," said former shrimper Curole.
The area that the slick was bearing down on is "a veritable highway for so many different kinds of animals -- tropical migratory songbirds, shorebirds, seabirds, raptors all move through that zone," said Rader.
Experts fear the wind will push the oil inland into the sinuous network of tributaries that feed off the marshes in the delta area -- and then remain trapped in the marshland's tall grasses and tiny pockets of water.
"The wetlands in the Mississippi delta are the most important wetlands on the entire continent and right now, that's where all the migratory birds are nesting," said Dean Wilson, keeper of the Apatchafalaya Basin, which lies to the west of the Mississippi delta.
Louisiana's state bird, the brown pelican, which was removed from the list of endangered species in November last year, is among the birds that pass through the delta on their way to warmer climes, dipping down into the marshes and onto the beaches to snap up fish to eat.
Even if the pelicans and other birds aren't directly affected by the slick, the plants and fish they eat will inevitably be caught in the pollution.
And as time goes by and the Gulf's waters are cleaned up, all the fish and fowl that move through the region will ingest and recycle toxins from the BP spill that have worked their way into sea and land food chains.
"This region has one of the biggest concentrations of sensitive marine ecosystems in the world, and a very tight dependence of human societies and economies with those marine systems," said Rader.
"And that raises the specter of this becoming one of America's greatest environmental catastrophes."