Stoat

Braided River Status

Commonly found along braided rivers.

Description

Introduced into New Zealand in the mid-1800s, the stoat is a member of the mustelid family, along with the smaller weasels and the much larger ferrets. Stoats are now considered “public enemy number one” for New Zealand birds.

Similar in colour and general appearance to weasels, stoats (Mustela erminea) are larger, have longer tails with a distinctive bushy back tip and there is a clear demarcation in colour from the reddish-brown fur on their backs and their yellow-white belly fur. Stoats are 350-400mm long from nose to tip of the tail. At 325grams males are generally considerably larger than females, which are about 205 grams, though this may vary from region to region. In alpine areas, some stoats develop a pure white winter fur, (though this is rare in New Zealand) and referred to as ermines. Stoats have acute sight, hearing and smell, and may have some colour perception.

Stoat

Why are they a problem?

• • Agile and excellent climbers, stoats hunt at any time, day or night

• • Rapid reproduction rates

• • Will happily cross water; braided rivers birds nesting on temporary gravel islands are no less vulnerable than those nesting near riverbanks

• • Inhabits all regions, from alpine to coastal

• Known predators of native birds, reptiles and invertebrates

Conservation Activities

• Trapping. The DOC 150 and 200 are effective for stoats
• Where you can buy  or order DOC 200 traps ($60 each)

• If you are interested in helping out with or starting up a local trapping programme, please contact your nearest DOC office, enrol in DOC’s animal Pest Control course, or contact one of the local rivercare groups.
• If you believe you have mustelids on your property, you can purchase a trap here – they will gladly show you how to use it.

Stoat traps with stoat (left) and ferret (right).

More information

• Stoats (DOC)
• Pest Detective: Stoat

• Kill a Stoat and Save New Zealand (Radio NZ National)
• DOC traps: all the information you need
• Wildlife Ecology and Management (Landcare Research)
• Animal Pest Control course (DOC)

Research papers

• Norbury et al (2013) Invasive mammals and habitat modification interact to generate unforeseen outcomes for indigenous fauna ESA  doi: 10.1890/12-1959.1