Possums under siege in Southland control areas
Southland possums are facing a losing battle with more than 300,000 hectares of land now part of a highly successful control programme.
The programme reached the major milestone this month, just eight years after the first Possum Control Areas (PCA) was established.
Senior biosecurity officer Dave Burgess said the success of the programme was largely due to the commitment of landowners who had recognised the significant economic and environmental impacts of managing possums on their properties.
"Most landowners are aware of their responsibilities for possum control, however having large areas in designated PCAs reduces the chances of possum reinvasion between neighbouring areas and achieves a much better level of control with everybody working together."
Environment Southland biosecurity staff support and assist landowners within the areas, by carrying out initial possum control work at no cost.
The team had managed to set up about five control areas every year since the project's inception. Burgess said the process to create them involved a lot of work from staff who visited all of the farmers and landowners in the area to try and get them on board.
"We make sure possums are reduced to a low level that landowners can effectively manage and maintain. Sometimes areas don't require an initial control programme and then we go straight to the next phase of setting up bait stations in areas of prime possum habitat."
Burgess said landowners were then provided with ongoing support and were strongly advised to use a recommended contractor. Farmers were generally on board with the programme, he said.
"The benefits of good possum control are substantial, not least for the impact on improving biodiversity. Possums can devastate native flora and fauna and one of the early signs reported by landowners who have achieved good possum control, is the return of birdsong to their property."
Initially, the programme followed up the work of the TBfree programme to continue the control of possums once the risk of tuberculosis had been removed.
"Farmers didn't want to see possum numbers grow," Burgess said.
While the programme had reached a milestone this month, Burgess doubted whether it would be able to encompass the entire region. There were a lot of areas in Southland where the habitat and terrain would be too harsh to warrant a control area, because the cost would outweigh the benefit, he said.
"We're trying to pick areas that have got the most benefit."
Predator Free 2050 aims to rid New Zealand of possums, rats and stoats by 2050. However, at this point it was unlikely Southland would be rid of possums by 2050, Burgess said.
The research and development of an eradication tool had yet to be completed, so for now the aim was to keep possum numbers at a low level, he said.