The Animal Health Board has asked for permission to release 10 feral pigs into the Hokonui Hills in a trial to detect the presence of bovine tuberculosis in the remaining possum population.
AHB national disease control manager Garry Knowles said pigs were excellent scavengers that readily picked up possum carcasses, and research had shown pigs were easily infected by TB.
Possums are the main wild animal TB "vector", which spread the disease to cattle, and in 2004 the AHB conducted an aerial operation in the Hokonui Hills using 1080 poison, successfully reducing possum numbers in the area.
On July 9, a report was put to the Environment Southland regional services committee and a recommendation made that the AHB be exempt from rules 1 and 3 in the ES regional pest management strategy, which relates to the release of feral pigs in Southland.
It was stated in the report that no further evidence of TB had been found in autopsied possums from the area. However, three TB infected ferrets were caught in 2006.
Mr Knowles said before the release, proposed 2008/09, each pig would be fitted with a radio collar which allowed for GPS tracking and for data to be downloaded throughout the project
He said it was essential the "sentinel pigs" were free from TB, and so would be captured from a known TB free area in the Marlborough Sounds and tested for the disease, before being transferred to Southland.
The pigs would be released into separate areas of the Hokonui Hills and left for a period of up to 12 months, after which they would be caught and collected for a TB post mortem.
Mr Knowles said the possum population was "extremely low" in the Hokonuis and only a few "pockets" of TB remained.
"It's needle in the haystack stuff," he said.
Mr Knowles said if TB was found in any of the sentinel pigs a ground crew would return to where the pigs had been scavenging and undertake "intensive possum control".
He said the AHB was not planning to use 1080 again, but would instead take a "targeted approach" to wipeout the remaining sites of TB infection in the wild animal population.
The report to the council said the sentinel pig trial would form part of a national experimental programme, aimed at the eradication of TB from New Zealand.
