Mass bird and fish deaths stoke curiosity

WASHINGTON - Five thousand dead blackbirds rained from the sky on the first day of the New Year in Arkansas. Then more dead birds fell in other states. Then huge fish kills were discovered in multiple US waterways.

And suddenly it became a worldwide phenomenon, with reports of mass die-offs of birds and fish in Sweden, Britain, Japan, Thailand, Brazil and beyond.

Doves, jellyfish, snapper, jackdaws... it seemed no species was immune.

Conspiracy theorists, doomsdayers and religious extremists warned that the end was nigh.

Could it be astronauts testing a potent sound beam to ward off aliens? The US military experimenting with satellite-powered energy weapons?

What about chemical sprays, meteor showers, or earthquakes activating pollutants from the BP oil spill in the Gulf of Mexico?

"Birds" surged to the most searched term on The New York Times website.

Religious bloggers loaded their sites with Bible verse, Hosea 4:1-3: "The land dries up, and all who live in it waste away; the beasts of the field, the birds in the sky and the fish in the sea are swept away."

But as speculation roiled the blogosphere, wildlife experts rolled their eyes.

"It is not that unusual," said Kristen Schuler, a scientist at the US Geological Survey's National Wildlife Health Center.

"There is nothing apocalyptic or anything that is necessarily out of the ordinary for what we would see in any given week."

Indeed, the USGS keeps a log on its website with reports of groups of birds dying each week, averaging from dozens to thousands.

Regarding the bird deaths in Arkansas, where the local custom is to set off fireworks to mark New Year's Eve, officials determined it was likely that the noise set off a deadly bird panic.

"It appears unusually loud noises, reported shortly before the birds began to fall, caused the birds to flush from a roost," the USGS National Wildlife Health Center said in a statement posted on the Arkansas Fish and Game Commission website.

"Additional fireworks in the area may have forced the birds to fly at a lower altitude than normal and hit houses, vehicles, trees and other objects. Blackbirds have poor night vision and typically do not fly at night."

In Louisiana, Schuler said it looked like cold weather might have killed off about 500 birds.

Meanwhile in Maryland, locals were spooked by reports of some two million dead fish in the Chesapeake Bay.

But officials were quick to assuage those concerns, saying the deaths were a result of an unusual cold snap, combined with an overpopulation of a species known as spot fish.

"Natural causes appear to be the reason for the deaths of the fish," said a statement by the Maryland Department of the Environment.

"Spot may have difficulty surviving in colder temperatures, and the species’ susceptibility to winter kills is well-documented," it said, noting that surface water temperatures last month were the coldest in 25 years.

As for the bird and fish deaths elsewhere in the world, many were still under investigation.

According to the National Wildlife Federation's Doug Inkley, the most frequent cause of mass death in birds is disease, though pollution and "just plain accidents" can also trigger large scale die-offs. Often, people just are not aware of them.

"Most of the time these areas are not near human habitation such as in forests or in the woods," he said on CNN.

But in today's Internet Age, when hardly anything remains secret, word of mass bird deaths has spread with unparalleled speed.

"In 1960 if a bunch of birds started falling from the sky it may have been noticed by some people. It may have gotten reported in the local paper, but it may never have gotten any further than that," said Robert Thompson, professor of pop culture at Syracuse University.

"Now some of these kinds of stories, because they get out there on the Internet, if they are compelling enough they can immediately make this jump to national news," he said.

"Let's face it, big quantities of birds falling from the sky or fish going belly up is a pretty compelling story."