Hundreds of dead seabirds washed ashore this week and dozens more were found dying on beaches spanning almost the entire Florida east coast.No one knows why, but scientists suspect starvation. Frantic beachcombers dropped off about 130 greater shearwaters -- gull-like birds that prefer the open ocean -- to Brevard County rescue centers in the past 3 days. The die-off of birds ranged about 300 miles (about 483 km), from Hobe Sound in Martin County to South Ponte Vedra Beach in St. Johns County.Scientists suspect recent winds and currents disrupted the birds'food fish supply. But they also plan tests to rule out algal toxins, bird flu, parasites, metals, and other common causes of seabird deaths."The preliminary findings indicate starvation," said Wendy Quigley, spokeswoman with the Fish and Wildlife Research Institute in St.Petersburg. "We're basically seeing emaciated birds."The institute received reports of at least 200 carcasses along the East Coast since Saturday [16 Jun 2007]."As only one species appears to be affected, and the sick and dead birds have similar symptoms, we believe the seabirds are suffering from the same ailment," said Dan Wolf, research biologist at the institute.A similar but much less severe shearwater die-off happened in 2005.Shearwaters are one of the few birds that breed in the south and migrate north. They loop the Atlantic, 1st breeding on South Atlantic islands, then heading up the eastern seaboard of South America and North America around this time of year, ultimately crossing the Atlantic in late summer. Storms at sea can weaken, dehydrate, sicken, or kill them. They feed on fish and squid, diving from great heights to chase their prey underwater with partly open wings and paddling feet.Local birders have been chatting online this week about all the shearwaters they see flying south -- the wrong way for the birds'usual summer migration -- in what the observers believe is a desperate search for food. "There's been a lot of buzz," said David Simpson, a state park service specialist at St. Sebastian River Preserve. He suspects sparsely scattered tuna may be contributing to the die-off. Fishermen in South Florida recently have reported difficulty finding schools of tuna because strong easterly winds dispersed the fish. The shearwaters follow the schools of tuna because the larger fish scare smaller bait fish to the surface, where shearwaters can snatch them.People have been flooding animal rehabilitation centers along most of Florida's East Coast with dying shearwaters. At least 120 in 3 days were brought to the Florida Wildlife Hospital and Sanctuary in Palm Shores. Half were dead days later."It's difficult to test enough to isolate the problem," Sue Small, the hospital's director, said over squabbles from about 50 shearwaters in the sanctuary's cages. About 10 shearwaters were brought to the Wildlife Care Center in Canaveral Groves in the past few days. All died. The center fielded calls about 10 other sickly shearwaters that it referred to state wildlife officials."This has got to be something big with all of them dropping dead,"said Jennifer Sypien, president and director of the Wildlife Care Center. She recently treated birds with botulism and heartworm-like parasites but didn't know if that's what's killing the shearwaters."I haven't heard of any of them surviving," she said. "It's a tragedy. One after another is just dropping dead." Small said usually only 10 to 15 percent can be saved. "We hate not to try," she said, "even though we don't have a very good success rate."The die-off is reminiscent of March 2003, when about 200 gannets washed in either dead or starving on Brevard beaches. The cause was never determined, but some fishermen guessed a temporary lack of bait fish.Harmful algae blooms also can cause bait fish declines or can emit toxins that kill birds. No such blooms have been detected this week in Florida. And no beach advisories or warnings of high bacteria levels have been issued this week in Brevard.Nonetheless, Mendy Gaither of Salisbury, N.C., worried Tuesday [19 Jun 2007] about the water off Satellite Beach. "We kept seeing the dead birds," Gaither said. "There doesn't seem to be that many birds here."
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