The Bio Report: Tracking Tunnels

A light morning rain left the surrounding bush damp and the high humidity left my skin feeling sticky. Walking past the tree ferns, their wet fronds transferred water droplets to my clothes. Keeping my head up, I was always searching for the next flourescent flagging tape marking the weareabouts of the next tunnel. Without the flagging tape and with no GPS, it would be almost impossible to find your way through the bush. It was nice working in the bush again to help with pest management. Just a month ago New Zealand was in lock down due the COVID pandemic.

Palm beach evening

Today I was helping Natasha who is an Auckland Council ranger in Waiheke's Whakanewha reserve monitor for pests using tracking tunnels. Ten tracking tunnel networks were more or less randomly placed in the reserve. Each tunnel network has ten tunnels that get an ink card and a spoonful of peanut butter in the center. Left overnight, hungry critters come to feast and unknowingly leave their footprints behind. The goal is to have rats tracking (RTI) at 5% and of course higher percentages of native species such as weta, skinks, and geckos. A tracking rate of 5% means that bait stations and DOC200s are doing their job. Rats tracking at less than 5% can be a good thing but can also lead to issues such as an explosion in mice. Ecology is funny like that.

Best practice would be to track before and after a bait pulse but due to limited resources, this generally is not feasible. Many groups aim to monitor quarterly and log their data to help develop pest trends overtime. It's always exciting pulling the tracking cards out of the tunnel. It's almost like opening a birthday present and hoping that you are going to get something cool. Sometimes you do and sometimes you don't.