Monitoring to detect mice

The Antipodes eradication team have been busy monitoring

Written by Stephen Horn – Project Manager

Tracking tunnels for detecting mice have been deployed on Antipodes Island as well on the offshore islands including Bollons, Leeward and Windward Islands. Each device station contains a tracking card and a bait positioned in the middle of the card. As mice move into the tunnel they walk across a black ink pad to access the bait, leaving their signature footprint on either end of the card confirming their presence and depending on number of tracks, giving some indication of the density of the population.

Finlay setting up biosecurity network

Mouse tracking tunnel

Mouse tracking tunnel

Following the bait application to eradicate mice, 15 tracking tunnels were placed around the field camp and coastal areas around the Hut Cove and Anchorage Bay and also at an elevated plateau site on the North Plains.

The tracking tunnels were monitored daily when possible on Antipodes Island and when the weather was conducive to access the offshore islands. None of the offshore island monitoring stations showed the presence of mice.

The tracking tunnels around the coast fell away to zero tracking approximately 10 days after the first bait application. We continued to track mice until close to the completion of the second bait application around the field camp before tracking went to zero and bait take from the trays around the infrastructure stopped.

Mice are almost impossible to detect at low density and much of Antipodes Island is steep and inaccessible so these results are not sufficient to say if the eradication attempt was successful but provide interesting data about the period required for mice to succumb. Rodent detection dogs and monitoring tools will be used on site in 2018, two potential mouse breeding seasons after the eradication attempt. This gives sufficient time for any remaining mice to have bred to detectable levels if the eradication was not successful. If no mice are detected at that stage we can be confident they have been eradicated.

Many of the monitoring tools have been set up as part of a long term biosecurity network to be checked upon the arrival of any visitors to help protect against the risk of any future incursion.

Bird and insect monitoring have also been a big focus for the team. Watch this space for these updates from the island.