Toxic wetlands may be cause of thousands of bird deaths in Western Australia

January 14, 2007 Western Australian government authorities say they believe a toxin may be responsible for the recent mysterious death of an estimated 5,000 birds found in the area of Esperance - on the state's south eastern coastline. Autopsies by toxicologists from the WA Department of Agriculture will test for organochlorins, organophosphates and heavy metals.

Esperance residents first noticed large numbers of dead birds littering their streets and gardens on December 7 last year. Populations of honeyeaters, wattle birds and miners have reportedly been effected.

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

The DEC says it has failed to figure out the cause of death despite interviewing industry groups, farmers, grain handlers and timber companies about pesticide and chemical use.

Birds Australia, the peak group dedicated to the conservation, study and enjoyment of Australia's native birds and their habitats, said it had not heard of a similar occurrence. "Not on that scale, and all at the same time, and also the fact that it's several different species," chief executive Graeme Hamilton told the Sunday Times. "You'd have to call that a most unusual event and one that we'd all have to be concerned about."

Mike Fitzgerald said the DEC were looking at something "pretty potent." "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."

The deaths could be a result of a drier than normal winter, causing algal and bacterial blooms in the Esperance Lakes Nature Reserves. Esperance recorded 457mm rainfall in 2006; the average is 620mm.

Initially, health authorities feared a virus, such as the deadly avian 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 - who lives close to the worst-affected area. Dozens of native birds began dying in her back yard a week before Christmas. She says she contacted neighbours to discover if 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.