Dead birds rain down on towns half a world apart

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Dead birds rain down on towns half a world apart



It could be the plot of a horror film, but in two towns on opposite sides of the world the mysterious phenomenon of thousands of dead birds dropping out of the sky is all too real.

Officials are baffled by the unexplained deaths which have affected Australia and the U.S.

Three weeks ago thousands of crows, pigeons, wattles and honeyeaters fell out of the sky in Esperance, Western Australia.

Then last week dozens of grackles, sparrows and pigeons dropped dead on two streets in Austin, Texas.

As birds continue to die in Esperance and the town's dawn chorus remains eerily silent, vets in both countries have been unable to establish a cause of death - despite carrying out a large number of autopsies on the birds.

Wildlife officials from Western Australia's Department of Environment and Conservation said they were baffled by the "catastrophic event" but emphasised the deaths had nothing to do with a severe storm which recently struck the area, as the birds had started dying before then. District nature conservation coordinator Mike Fitzgerald said: "It's very substantial.

"We estimate several thousand birds are dead, although we don't have a clear number because of the large areas of bushland."

Birds Australia, the country's largest bird conservation group, said it had not heard of a similar occurrence.

"You'd have to call it a most unusual event and one that we'd all have to be concerned about," said chief executive Graeme Hamilton.

Dr Fiona Sunderman, chief veterinary officer of the Department of Agriculture and Food, suspects the cause of death is some form of toxic poisoning.

Esperance resident Michelle Crisp, who normally sees hundreds of birds roosting in her garden, counted 80 dead ones in one day.

"It went to the point where we had nothing, not a single bird," she said. "It was like a moonscape - just horrible."

In Texas, officials are also working on the toxic poisoning theory. Adolfo Valadez, medical director for Austin and Travis County Health and Human Services, said it might be weeks before any conclusive results were known.

Such was the concern that the birds suffered deliberate toxic poisoning that several streets were closed in Austin while police and fire crews checked the area for any substance that might be of harm to humans.

"This was a precautionary measure. We certainly take these kinds of thing seriously, especially following 9/11," said Mr Valadez. "It may be a matter of time before we know what happened and why it happened. There is no threat to public health."

Federal officials in Washington said they were monitoring the situation, but a spokesman for the Department of Homeland Security said: "There is no credible intelligence to suggest an imminent threat to the homeland or Austin at this time."

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Re: Dead birds rain down on towns half a world apart

Salty Water Cause Of Deaths

November 2006

A combination of thirsty birds and salty water likely resulted in the deaths of about 1,000 snow and blue geese at Lake Nicholson.
Personnel from the S.D. Game, Fish and Parks Department reported the bird deaths on the lake about 15 miles northwest of Watertown in late November of 2006. Biochemical analysis on the brain tissue of some of the dead birds, while not conclusive, did reveal a high enough sodium concentration to suspect that salt toxicity led to their deaths.
"It appears that the birds came into the Lake Nicholson from other lakes with less salinity, became ill and died within a matter of hours of drinking the salty water," according to Will Morlock, GFP regional game manager. "The dead birds were all blues and snows. It doesn't seem to affect Canada geese or ducks."
Morlock said the effects of salt toxicity are noticed within a few hours. "Those birds that survive in the initial shock to their systems appear to get along fine," Morlock said.
Waterfowl die-offs on lakes in that area are not uncommon. Morlock said as many as 2,000 snow geese and blue geese died on Medicine Lake in the mid 1980s. A similar die-off took place in the 1930s.
"All birds collected from the die-off were also tested for various strains of avian influenza and those tests eliminated bird flu as a cause of the die off. Although not confirmed, evidence strongly indicates that these birds succumbed too much salt in their systems," Morlock said.
GFP, along with wildlife agencies across the nation, took part last year in a multi-state testing of live birds and hunter-harvested samples looking for highly pathogenic avian influenza, otherwise known as bird flu. Of the more than 1,000 waterfowl and shorebird samples collected by GFP, none tested positive for highly pathogenic bird flu.