Pests also use commuter corridors
Transmission Gully is a quicker route for something we absolutely don’t want.
Kō kako and kiwi at Pukaha Mt Bruce in the Wairarapa are also threatened by predator migration.
As reported back to the Greater Wellington Regional Council environment committee which I chair, the regional council is seeing possums and mustelids using landscape corridors such as roads, waterways and coastlines as pathways.
As I shared in interviews on radio and TV1’s Breakfast, Transmission Gully is a particular concern, and for those of us on the Kā piti Coast, we know how the Kā piti Expressway has been a commuter corridor for pests as well as humans.
Predators, such as possums, ferrets, stoats, and weasels, can move large distances thanks to the roading corridor, favouring the easy-to-access pathways such as those created by Transmission Gully, and therefore reinvade areas where control has been undertaken.
Targeting these pathways with control methods will slow the pest immigration across the landscape and provide protection on a wider scale where we cannot do intensive
control.
We are particularly concerned about ferrets migrating down the Kā piti Coast and into the wider Wellington region, where they are rare.
Ferrets predate upon groundnesting birds, including kiwi and are capable of killing adult kiwi, unlike stoats which primarily take chicks.
There are some areas that were previously controlled but which are now under threat, including possumfree Whitireia peninsula, Baring Head and Parangarahu Lakes where dotterel colonies are located, Wairarapa Moana, home to endangered bittern, and the western hills of Wellington around Makara where kiwi are now establishing
thanks to Capital Kiwi.
Kō kako and kiwi at Pukaha Mt Bruce in the Wairarapa are also threatened by predator migration. A previous ferret invasion at Pukaha resulted in the loss of 50 per cent of the adult kiwi population in a matter of weeks.
Thankfully we have not yet discovered any extensive damage from recent predator incursions in these areas, but are working with Waka Kotahi to help increase their pest management.
Predator migration to high-value biodiversity areas will threaten native animals and vegetation at risk and will require an intensification of control methods.
As part of the Greater Wellington long term plan process, we are considering options to target predator control pathways such as those created by Te Aranui o Te Rangihaeata/Transmission Gully.
We hope to work with partners including councils, agencies like Waka Kotahi NZ Transport Agency and the community to slow predator migration along these pathways and provide protection on a wider scale.
Currently, Waka Kotahi has contractors shooting goats and deer to protect their plantings, but no other pest control.
Ideally we’d like them to expand that to rabbit control and collaboration on further ungulate and mustelid control.
Volunteers are also a huge help, and here on the Kā piti Coast we have dedicated people trapping in and around Queen Elizabeth Park, catching stoats, weasels, rats, mice, hedgehogs and possums.