Western Australia’s Department of Environment and Conservation (DEC) has been unable to determine what killed up to 4000 nectar-eating birds in and around Esperance between December 7, 2006 and January 2, 2007.
The birds, mostly yellow-throated miners, wattle birds, new holland honeyeaters and silvereyes, plus some seagulls and pigeons, were found dead near water sources such as sprinklers and water tanks.
The DEC said bird viruses and bacteriological causes had been ruled out as the cause of death and toxins were still the most likely culprit.
DEC Nature Protection Branch manager Dave Mell today said the department had recently received reports of groups of dead birds - up to as many as 200 - at Yealering, Kellerberrin, Cunderdin, Kulin and Kukerin, in the state’s wheatbelt.
But Mr Mell said he did not believe the deaths were related to those around Esperance.
“The recent deaths have coincided with high temperatures of up to 45 degrees Celsius and strong winds, and we believe it’s most likely the deaths can be attributed to the extreme weather conditions,” Mr Mell said.