Halo Likens Stoats to Rock Stars!
Stoats are notoriously difficult to control due to their biology. They are small animals with a big attitude and fast-paced life — short-lived, high metabolism and reproduction rates, plus highly skilled at what they do — just like a classic rock star. But these are common unwelcome predators.
Around Ōtepoti Dunedin, stoats are found anywhere from beaches and dunes to forests and farms, but more commonly in forest. On farms, they move around under vegetation cover, out of sight from kāhu/harriers, kārearea/falcons, cats and ferrets.
Stoats are good climbers, easily reaching nests in tree hollows and feeding on eggs, chicks and adult birds (including kākā), mice, rabbits, hares, lizards and wētā (and other insects). They hunt frequently, day and night, by climbing trees, invading nests and investigating every hole or burrow on the ground. They can even swim to the islands in the harbour in search of food.
Females raise litters of around seven kits annually. Young stoats disperse from their den during summer, when birds are on the nest and chicks are fledging – making perfect prey.
Upping the effort to trap young stoats as they disperse from their den and when birds are most vulnerable is an effective way to control the predator and protect the prey.
A large stoat caught in a double DOC200 trap box. Photo: Halo Project.
Halo’s newly completed stoat trap network, stretching from Heyward Point to Flagstaff, includes DOC150s, DOC200s and A24 autotraps, totalling 1866 active traps. Staff and volunteers are working hard to ensure every trap is checked fortnightly and freshly baited with enticing rabbit. Lots of work is done in preparation for the busy period - traps are cleaned and calibrated, volunteers rallied, vegetation cleared from the entrances and fresh rabbit sourced for bait.
Half-way through the season, the tally is lower than last years’ even though it covers a larger area: with 58 stoats trapped in December and January 2020/21, compared to 48 trapped in December and January this summer. What this means is hard to be sure of just yet, but we are hoping it signals that stoat numbers are being reduced by continuous trapping.
Map of stoat catch locations this summer (December 2021 and January 2022), showing that more than half were trapped in the Flagstaff/Leith Valley area in new traps, and fewer stoats were caught in the areas that have been trapped for the past three years (around Orokonui, Heyward Point and Dean’s Valley).
Map of stoat catch in previous summer (December 2020 and January 2021) showing higher catch.
Monthly total stoat catch from December 2018 to February 2022. Note the peaks in stoat catch in each of the four summers, with smaller peaks in autumn, when food becomes scarce and bait becomes attractive.
The boost of funding for Predator Free Dunedin means stoat control across 12,500 ha can continue for a further two years through 2025, to reduce stoats and keep numbers low. Plus, we’ll be working in partnership with Wenita to control stoats across Mt Allan forest.
This is great news for birds and other wildlife. More observations of titipounamu/rifleman, kakaruwai/robins, kākā and ruru/morepork are being recorded beyond Orokonui’s predator fence.
Over the next few years, we hope stoats will be more like a rockstars – you’ll be lucky to see one on their occasional appearances.