A predator plague that will pose a serious threat to our endangered native wildlife is being predicted by scientists this autumn.
High levels of seed production (mast) in our beech forests are expected to trigger a rodent and stoat explosion later this year. When seed supplies run out these predators will turn on endangered birds such as mohua, kaka, kea, whio and kiwi along with other at risk species like bats and land snails.
Mast events are prolific flowering bursts among forest trees, like beech, over spring and summer. This flowering in turn leads to a bumper seed fall in the following autumn and the widely available seed on the forest floor drives a rapid increase in rat and stoat numbers.
Rats and stoats both prey on native species and the surge in the predator population puts vulnerable natives species under extreme pressure, particularly during the spring when birds are nesting and raising chicks.
In anticipation of this year’s mast, the Department of Conservation will implement a special predator control programme called Battle for our Birds. You can find more information about masts, the programme and where control is being targeted on DOC’s website www.doc.govt.nz.
Private landowners and covenantors can take extra steps to knock back predator numbers after forest mast events. If you are already doing seasonal predator control work, Trust regional representative and pest control expert, Trevor Thompson, recommends an earlier start (early September) followed by more regular checks of bait stations and traps. If your beech forest area is contiguous with a larger beech forested area then a buffer zone should be established, if permitted.
If your covenant is affected by a mast event, contact your regional representative to discuss a pest control regime that will help you target rodents. For rat control tips and toxin options refer to Open Space magazine issue 80, March 2011 (magazine also available on our website at this link).
NPCA (New Zealand Pest Control Agencies) have a number of helpful resources available at this link http://www.npca.org.nz/index.php/publications/a-best-practice/157-a-series.