Written by Kennedy Zittel, Naturalist
Wisconsin is home to 8 species that come from the Mustelid Family (weasels). These species include: Fisher, Mink, American Marten, River Otter, Badger, Short-tailed Weasel, Long-tailed Weasel, and the Least Weasel. Woodland Dunes has documented 7 out of the 8 species, some much more frequently than others. We have not seen the American marten, as they do not live in this part of the state. Mink and short-tailed weasels are common sightings here, both in person and on a trail camera. The river otters are next, more common to see on a trail camera and less common to see in person, however, a handful of visitors have gotten to see them at the end of Cattail Trail. We have documented a badger on a trail camera, but the animal was likely passing through the area. We have not documented the long-tailed and least weasels since the early surveys done here. Does this mean the long-tailed and least weasels are gone from our preserve, or simply hiding out of sight?
Let’s find out!
Weasels are very elusive, as such it is hard to determine their population size, or in our case if they are even here. Having around 1,500 acres certainly leaves a lot of space for a weasel to live without being seen by people. This summer, our education intern, Natalie, and I came up with a fun research project to try and determine if there are any long-tailed or least weasels left in the preserve.
How can we do this? Camera trap boxes!
Camera trap boxes are not actually traps, as animals can choose if they want to enter the box, and can leave at any time. I made our boxes out of plywood, around 2 feet long by 1.5 feet wide. A 4 inch wide pvc pipe runs through one side of the box and out the other end, creating a tunnel. The pvc pipe has a window cut into the part that sits inside the box. A trail camera is placed at the end opposite to the pvc pipe, aimed at the opening. The idea is that weasels are naturally curious animals and are known for exploring tunnels. Without even needing to add bait to the box, a weasel will enter the pvc tunnel, when it enters the box the trail camera will take its photo. Afterwards it can walk right out the other end of the pipe. I will add a ruler to the inside of the box, to help us determine what species are entering, as well as a label so we know when looking at the images what box it came from. An additional trail camera will be placed somewhere nearby, facing the box so we can see what other animals are nearby.
Are the boxes weasels only? Nope! Other camera trap box projects have documented a variety of animal species entering the boxes. We are excited to see whatever animals decide to enter the box, but are keeping our fingers crossed for weasels! Once the boxes are placed I will check the trail camera’s SD cards every few months – so it is definitely a more long-term project, but an easy way to try and document species. Stay tuned for future updates!