Weka benefitting from 1080 pest control programmes:
On the South Island's West Coast, the Lady Lake and Bell Hill Scenic Reserves are both in the Grey River catchment between Nelson Creek, Moana, Rotomanu and Haupiri. This formerly pakihi country has been the focus of major land development by Lands and Survey then Landcorp over the last 30 years. Prior to that it was heavily mined for gold and the focus of native forest logging and considerable conversion of native forest to pines and rough pasture.
Small scenic reserves link with hill country forests and with patches of bush protected by Lands and Survey in their farm developments. There are dairy farms and sheep and beef farms. A major issue is the presence of TB infected possums that have infected a number of the dairy herds here. For the last 30 years this area has been the focus of major AHB-West Coast Regional Council 1080 programmes to reduce TB infected possum numbers and create infection free deer and cow herds.
If anywhere was to demonstrate any negative impact of 1080 programmes on native birds it would be evidenced by a collapse in bird numbers in the Bell Hill and Lady Lake Scenic Reserves.
Yesterday at 4pm, 4 of us stopped at Bell Hill Scenic Reserve to look at the rimu forest. A weka wandered out of the forest to say hello. We drove about another 6 km south and stopped at Lady Lake Scenic Reserve to photograph the late afternoon sun setting behind the kahikatea and flax of this lake. There were tui singing all around us in the tops of the giant kahikatea. A robin flew onto the roadside beside us and posed for the camera. Then a flock of fantails, 4 pied fantail and 1 black fantail, started flying all around us. The highlight was 2 weka as tame as anything emerging from the bush right next to us and fossicking around for food.
Right next to us nailed to a tree on the road side was the required public notification from pest control company Vector advising that 1080 poison had been applied to all the forest around Bell Hill - Lady Lake on 23 March 2011. Because of this, the Lady Lake forests had birdlife nearly as rich as what you would encounter on a pest free off shore island.
We must never underestimate the enormous benefits for native birds that come from Animal Health Board (TB Free NZ) operations.
Our visit was just a snapshot in time but if you map the distribution of western weka against AHB 1080 operations over the last 30 years in the South Island, you will note that almost everywhere that had surviving weka populations 30 years ago AND where there have since been AHB operations against possums (with the consequent by-kill of rats and stoats) weka are still thriving.
Where there have not been such 1080 operations, such as in Abel Tasman National Park and many parts of Golden Bay where weka were formerly abundant, weka numbers have today either collapsed or have even died out altogether!
We know that stoats are major predators of weka and we also know (from efforts by Forest and Bird North Island Branches) just how hard it is to re-establish weka once they have died out.
Has anyone else got observations or studies of weka in relation to pest control programmes?
Does the Animal Health Board deserve a special vote of thanks from the NZ nature conservation movement?
Attachments
-
Vector_1080_pest_control_sign_applied_.jpg (95.7 KB, 0 downloads) 12 months old - Lady_Lake_Scenic_Reserve_Sunset_22_May.jpg (69.4 KB, 0 downloads) 12 months old
- SI_Robin_Lady_Lake_Scenic_Reserve_May_.jpg (77.1 KB, 1 downloads) 12 months old