The highly contagious H5N1 strain of bird flu is expected to reach the Northern Territory soon, the Environment Department has said, with staff sampling faeces and water supplies to identify contamination.

The ABC reported NT Department of Lands, Planning and Environment senior director of species management Tony Griffiths said combating H5N1 in the NT would largely be based on surveying areas such as the Top End coastline and Barkly lakes and using bird enthusiasts to be on the lookout.

“It’s definitely going to happen. It could be weeks, it could be months, but it’s a national event, it’s the biggest national disease event that has ever occurred in Australia for wildlife,” Dr Griffiths told ABC News.

The flu was first detected in Western Australia in late June and has now been found in all six states.

Dr Griffiths said department staff had been sampling faeces and water supplies to identify contamination, but they were not going to vaccinate native species.

“We have 450 species of bird in the Territory and 37 of those are threatened, but we don’t rely on captive breeding programs to support the management of those species,” Dr Griffiths said.

“The threatened birds we have are dispersed over very large areas and it’s very difficult to catch them to vaccinate.”

NT chief veterinary officer Sue Fitzpatrick told the ABC backyard poultry farmers and other bird owners need to watch out for the disease.

“We’re looking for bird keepers to protect their birds from wild birds, enclose their runs and put some roof over their runs, protect feed and water sources from wild birds,” Dr Fitzpatrick said.