Weasels
Weasels…know your pest!
Weasel (Mustela nivalis)
Identification and habitat
While weasels overall are the least numerous of the mustelid species, they can wreak untold harm to NZ’s native ecosystems.
Weasels are the smallest mustelid in New Zealand. Males grow to about 20 cm long. Weasels are brown on their upper bodies and white below, similar to stoats and their tails are short, brown and tapering. To identify a weasel from a stoat, a weasel does not have a bushy black tip at the end of the tail whereas a stoat does.
Habitats
Weasels are most likely to be found in tussock grasslands, lowland forests and farmland. They prefer areas with an abundance of mice.
Behaviours
- They can hunt either day or night.
- While they prefer mice, they will easily hunt and consume birds, geckos, skinks and invertebrates (like wētā).
- They have fast metabolisms and therefore often kill and store food in dens.
Threats – why are they a problem?
- While not as large as the other two mustelid species, the weasel can still kill and consume many bird species larger than themselves. This means that ground nesting birds such as the banded dotterel, pipit and terns are very vulnerable.
- They are an extreme risk for skink populations and can hunt and decimate local populations in their home range.
- As they are extremely agile, they can take prey from more difficult locations that might have been safe from other predators, such as coastal cliffs.
DOC 150, 200 or 250 in a Wooden Tunnel
Description
- This is the classic all around trap, in differing sizes
Target Pest(s)
- DOC 150 – Norway rats, stoats, hedgehogs
- DOC 200 – As above, plus ship rats
- DOC 250, as above plus ferrets
- We’d expect all to be suitable for weasels.
Pros
- Traditional and proven tunnel design
- Durable
- Catches a variety of pests
Cons
- Heavier to carry in the bush
- DOC 250s are beasts to set
Our Comment:
These traps are the workhorses of most trapping efforts, tried and true! They are durable, and if you build your own boxes, relatively inexpensive. Go for the Doc 200, the all around performer.
Buy From:
- Borrow a DOC 150, DOC 200 or DOC250 for up to 3 months from Akaroa Trap Library for free (donations welcome)
- DOC 200, Trap only from Trapinator, $29+GST
Live Capture Tunnel Trap
Description
- Double entry – tunnel trap for live capture of animals and pests.
- An excellent cat trap, possum trap, animal trap, magpie trap and pest trap for humane live capture of most animals. sizes
Target Pest(s)
- Feral Cats, Possums, Ferrets, Stoats, Weasels, Rabbits, Hedgehogs, Rats
- No NAWAC approval required, as this only captures the pest
Pros
- Particularly good for trapping, trap shy animals
- A little fiddly to set, but you get used to it
- Catches a variety of pests
- Excellent door design, many cheaper traps have weaknesses allowing pests to escape, especially ferrets and stoats
Cons
- Short Supply
- Legislation requires traps to be checked at least once a day within 12 hours of daylight the day after it was set
- You have to kill the animal. (Note that drowning any animal is a prosecutable offence under the Animal Welfare Act)
Our Comment:
We’ve used these successfully to capture ferrets and feral cats, even ones that had escaped a previous less effective trap and were very trap shy. They are not cheap, but they are the best!
Buy From:
Weasel Fact Sheet
Download this information above as a Fact Sheet on Weasels.
Mustelid Trapping Tips
Information on how to catch the Mustelids.
Info on Stoats
Information on another one of the Mustelids: Stoats.
