The biosecurity response plan implemented by the Department of Conservation (DOC) following the sighting of a rat on Mana Island in November has paid off, with confirmation that a lethal dose of poison has recently been consumed.
“We were pretty happy when the bait blocks were checked and it was evident that the rat had nibbled on them. When the bait was weighed, it was confirmed that the rat had ingested a lethal dose,” DOC spokesperson Brent Tandy said.
Rodent detection dog team Miriam Ritchie and Occi arrive on Mana Island
Mr Tandy pointed out that, while this is good news for now, a body has not yet been found. However, no sign has been seen of the rat for over a week.
“Although all signs to date point to their being only one rat, we will continue extensive monitoring until we can be sure that there are no other threats to our precious island wildlife. Keeping our island nature sanctuaries pest free is a constant battle and we will continue to use traps, tracking tunnels and rodent detection dogs to monitor the island.”
Rodent detection dog team Miriam Ritchie and Fin Buchanan, with dogs Occi and Pai, visited the island shortly after the rat was first detected as part of this response. They identified four rat scent ‘hotspots’ on the island – an old shore plover nest site and three compost bins near houses.
Poison bait blocks were placed at the ‘hot spots’ and the bait was weighed and wired into the ground. Motion sensor cameras were also installed in the area. The rat was photographed visiting the old shore plover nest site on several occasions and it was at this site that it consumed the bait.
Miriam and Occi then returned to the island after the bait had been eaten but didn’t find a carcass. No sign of the rat was detected anywhere on the island, suggesting it may already have died.
Surveillance and trapping will continue on Mana Island until it is certain that there are no more rats. Even after this, periodic surveillance will be ongoing to detect any new arrivals
“Mana Island is an important breeding ground for endangered wildlife – including takahe, rare lizards, North Island robin and shore plover – and we will continue to do all we can to protect it,” Mr Tandy said.
People can help keep Mana and other treasure islands pest free by thoroughly inspecting boats, kayaks, clothing, footwear, bags and other equipment for pests before visiting our offshore wildlife sanctuaries. ENDS