The focus of the BP oil spill relief effort is shifting eastward – toward the beaches of Alabama and Pensacola, Fla. – as the slick’s toll on Gulf wildlife slowly mounts.

Tar balls bobbed toward Pensacola, threatening to make Florida the fourth Gulf state directly affected by the undersea geyser from BP’s Deepwater Horizon well off the Louisiana coast. As a result, federal and state governments are moving booms and skimmers eastward.

“There’s a lot of tactical movement of boom right now as the threat is shifting to Mississippi and Alabama,” says Coast Guard Adm. Thad Allen. Meanwhile, the National Wildlife Federation reported Wednesday that six to nine times more sea turtles are turning up dead than usual. Similarly, the 29 stranded dolphins found since the spill began represent two to six times the normal amount. So far, 444 birds and 222 sea turtles have been found dead in the area, according to a recent tally provided by the US Fish and Wildlife Service.

It’s not yet clear whether a higher than average dolphin mortality rate can be blamed on the spill, although she reported that “no oil” has so far been found inside the dead dolphins, says Jane Lubchenco, administrator of the National Oceanic and Atmospheric Administration (NOAA).

Species ranging from sperm whales to Kemp’s Ridley sea turtles, from pelicans to already depleted bluefin tuna, could all be impacted by the spill, scientists say. The degree to which dispersants being used have made the situation better or worse for sea life is one key question NOAA scientists will try to answer in an unprecedented federal study of the worst oil spill in US history. In Louisiana, 120 miles of shoreline has been inundated by oil from the spill. The oil slick spread toward the northeast on Tuesday.

Adm. Allen reported that tarballs and “sheen” had washed ashore on Dauphin Island, Alabama, and on Petit Bois Island, off Pascagoula, Mississippi.  Florida Gov. Charlie Crist said he expects tar balls to hit Florida “in a day or two.” As federal skimming boats move eastward, Alabama, Mississippi, and Florida are deploying booms to protect their valuable white sand beaches.

Florida officials say they are laying 66,000 feet of boom off the state’s three westernmost counties. A federal decision on whether to give the go-ahead to a proposed protective berm project across some Louisiana barrier islands is expected later Wednesday.