Why are weasels and stoats hard to find?
We had another first for our camera traps just after Christmas – the first weasel we’ve captured on video. It’s also only the second time we’ve captured a weasel on camera trap at all – the last (confirmed) being almost a year ago.
As you’d expect with such an agile and fast-moving animal, the weasel’s appearance was brief – but it did stand up to give us a good view (make sure you watch in HD).
Weasels are quite common throughout most of the UK, found in a wide range of habitats and estimates of their numbers are at around 450,000. That said, the Mammal Society’s MaWSE project (which collects all forms of sightings, including from camera traps) has recorded 1479 mammal sightings in the South East of England, of which weasel records make up just 2.91%.
So though it’s fairly common, it’s not often you see these tricky mustelids in the wild and even harder to capture them on camera trap – but why?
You can appreciate from the video just how small weasels are – in fact, they are the smallest native carnivore in the UK and only about 25cm long at most. Small animals can give camera traps the slip quite easily, as they give off less heat and have more subtle movement compared to a fox for example.
That’s one reason why they don’t often turn up on camera traps, but there are actually many more…
Weasels need to eat every 24 hours, and mainly hunt mice and voles. That means they need to be hunting frantically for most of the day and their small size means they can travel through small tunnels and holes in search of their prey.
Weasels also don’t like to be out in the open. Bad news if you want to capture them on camera trap, as it means they are often out of sight and moving very quickly.
It also makes them extremely hard to predict, so even if you have a camera trap in weasel-friendly habitat you could be waiting a long long time for one to turn up.
Once you do capture one, it may return; weasels do have home ranges.
The last time we caught a weasel was with camera traps out for our Yorkshire Pine Marten Project. The only reason we’d captured it was because it had been attracted by our smell lure, in the belief it was an easy meal.
Another issue is that they can sometimes become locally extinct after bad winters, and generally only survive to 2 years old. So if you see a weasel one year, it may not be around the next.
What about stoats?
Often confused with weasels, stoats again can be an enigma when it comes to camera trapping.
NatureSpy have had a little more success (or luck) when it comes to capturing stoats, including footage a few years ago of a stoat dragging a rabbit it had just killed…
Most of our captures however have been extremely fleeting and just mere glimpses of their giveaway black-tipped tail.
They are thought to be just as numerous as weasels, yet the same MaWSE project has only recorded 36 stoats so far, 2.43% of the total records.
Stoats are bigger than weasels and hunt larger prey such as rabbits. Crucially however, the stoat shares the weasel’s reticence for being out in the open, preferring to move along hedgerows or through scrub and ditches. Again, bad news for camera trappers.
Their biology and behaviour means that camera traps are not ideal tools for monitoring weasels and stoats, and any sightings of them are largely due to luck more than judgement.
However, that makes capturing them all the sweeter!
Have you captured a weasel or stoat on your camera trap? Let us know in the comments below…
Mammal Society, 2015. Weasel. Available online: http://www.mammal.org.uk/weasel
Mammal Society, 2015. Stoat. Available online: http://www.mammal.org.uk/stoat
Harris, S., Morris, P., Wray, S., Yalden, D.W., 1995. A Review of British Mammals: Population Estimates and Conservation Status of British Mammals Other than Cetaceans. Joint Nature Conservation Committee, Peterborough. Available from: http://jncc.defra.gov.uk/page-1741