A wildfire battled by fire crews at the Waituna wetlands since Monday night is under control but several species of rare birds are threatened by the damage.
It took five ground crews and three helicopters to bring the fire, which burnt through 498 hectares of the internationally-recognised wetlands, under control.
Several species of rarely sighted birds lived in the 500 hectares of the Waituna Wetlands Scientific Reserve destroyed by fire, with some of the birds nesting at the time of the blaze, experts say.
The rural fire authority's principal rural fire officer Mike Grant said although the flames had died down, there was still a lot of work needed to ensure the fire was completely out.
While weather conditions in Southland have been wet with average rainfall recorded, scrubby vegetation dries quickly after rain and can burn within two to three hours, even in cold conditions, he said.
''There will be crews out there today patrolling the fire perimeter and dampening down hot spots to ensure the fire is fully extinguished.''Fire investigators are continuing to examine the cause of the fire.
"This fire is an opportunity for people to think about what fire risks may be on their property. Although this fire occurred in a wetland it could have occurred anywhere" Mr Grant said.
"Fine, dry scrubby vegetation can be found around home gardens, farmsland, hedges and dry dead grasses at any time of the year.''
The Awarua Wetlands, near Invercargill, is one of the largest remaining wetlands and is recognised for its biological diversity, cultural values and bird life.
Conservation Department Southern Islands area manager Andy Roberts, who is also the Southern Rural Fire District's incident controller, said bird species in the manuka bush and wetlands in the Awarua Bay area included bitterns, fernbirds and crakes.