A second bird found sick on a remote beach in Western Australia's south coast has now tested positive for a deadly strain of bird flu, authorities have confirmed.Federal Agriculture Minister Julie Collins said testing at the CSIRO had confirmed both a brown skua and a northern giant petrel had tested positive for H5N1 avian influenza.Australian Federal Agriculture Minister Julie Collins.ABC NewsBoth birds were found in Esperance, about 700 kilometres south-east of Perth, and authorities confirmed on Saturday morning that the brown skua had the disease.Collins said there was no evidence of mass mortalities in wildlife, with the Australian poultry and agricultural systems remaining free from bird flu so far."We are working to determine whether the H5 bird flu has established in the wildlife or Australia, other than these two isolated birds," she said.The news comes as Ingham's, one of the nation's biggest poultry producers, announced earlier on Monday it was locking down its entire WA operations in response to the bird flu threat.- ABC