1000s of birds die around Esperance - Toxicity?

1000s of birds die around Esperance - Toxicity?

January 13, 2007 - WA government authorities believe a toxin may be responsible for the recent mystery deaths of about 5000 birds around Esperance. Toxic poisoning had emerged as the most likely cause of the deaths of thousands of birds around Esperance, 730km southeast of Perth. An autopsy being carried out by Department of Agriculture toxicologists on one of the latest casualties, will test for organochlorins, organophosphates and heavy metals...

The phenomenon has killed some 5000 birds since it was first reported in December. Populations of honeyeaters, wattle birds and miners have been hit. It was before the big December storm when Esperance residents first noticed large numbers of dead birds littering their streets and gardens.

The birds have been found vomiting and convulsing in bushland and suburban backyards over an extensive area. Department of Environment and Conservation (DEC) Esperance nature conservation coordinator Mike Fitzgerald says toxic wetlands near Esperance are the most likely reason for the mass bird deaths.

Mike Fitzgerald said they were looking at "something that is pretty potent," he said. "This is not a normal situation. The common thing that we have seen and heard is that the affected birds have an insatiable thirst... If it turns out to be a toxin that is responsible, that will raise more questions because there is no obvious source of exposure. It really is a puzzle."

Mr Fitzgerald said the deaths could be a result of the dry winter, which had caused algal and bacterial blooms in the Esperance Lakes Nature Reserves north of the town. Esperance recorded only 457mm rainfall in 2006. Its long-term average is 620mm.

Initially, health authorities feared a virus, possibly similar to deadly bird flu, was responsible. That was quickly ruled out, along with poisoning from bacteria or eating poisoned insects.

The first deaths were reported by Esperance resident Michelle Crisp, whose property is close to bush in the worst-affected area. Dozens of native birds began dying in her back yard a week before Christmas. She began ringing around neighbours and was shocked to find they were experiencing the same thing. Mrs Crisp found four dead birds, then 16, then 30 and finally up to 80.

Mike Fitzgerald said that any one of hundreds of toxins could be causing the deaths but so far all leads had not produced any answers.

Sources:
The Sunday Times - Day the birds fell dead
ABC - Esperance bird deaths mystify authorities
Border Mail - Toxin feared in deaths of birds
Perth Now - Autopsy may solve bird deaths