A Northwoods Almanac for January 14 – 27, 2011
by John Bates
Badgers
Al Denninger called me three weeks ago to report that he had three badgers coming in at night under his bird feeder and eating sunflower seeds. Al then called again last week to say he had noticed a large new hole dug in his yard, and when he went out to take a look at it, dirt started flying out of the hole! Al stood within five feet of the hole and watched the dirt fly until a young badger finally popped out and saw him. Interestingly, Al said the badger didn’t seem disturbed by his presence, allowing Al to get numerous good pictures.
Al wondered what the current status of badgers is in the Northwoods, given that in the nine years Al has lived at his home between Lake Tomahawk and Rhinelander, he had never seen a badger, and his neighbor, who has lived there since 1940, had never seen one until this summer when this small family showed up. It’s a question I’ve had as well because there’s very little research data available despite the fact Wisconsin is known as the “Badger State.” Even basic information like how many are in Wisconsin and where they are found are unknown.
I’ve always thought of badgers as a grassland animal which prefers sandy, treeless areas like prairies and meadows, and thus I’ve considered badgers to be a species largely confined to southern Wisconsin. But it turns out they do fine along forest edges, along old railroad tracks, and even along dirt roads and driveways, and are found in every county of northern Wisconsin, with particularly good numbers in Douglass, Burnett, Bayfield, and Langlade counties. In fact, the highest observation rates for badgers are in northern and central Wisconsin where sandy soils and jack pine savannas dominate. So much for badgers being a southern Wisconsin specialty!
It’s not known if badgers prefer one habitat type over another, or if they are equally adept at surviving in forests, agriculture, and natural prairie. Perhaps the key factors are how sandy the soil is and whether prey species are plentiful.
Badgers opportunistically eat almost anything the size of a woodchuck or smaller, and are adept at capturing burrowing mammals like woodchucks, 13-lined ground squirrels, chipmunks, and gophers. They’ll also take voles, mice, turtle eggs, ground-nesting birds, insects, and carrion, but to a less significant degree. Their consumption of 13-lined ground squirrels plays an important role in the survival of ground-nesting grassland birds whose nests are often raided by ground squirrels. Their large burrows also may serve as the initial excavations from which fox and coyote construct their dens.
Badgers patrol large home ranges, up to a square mile for females and two square miles for males, at least according to an Idaho study. Like most animals’ home ranges, if food resources are plentiful, their ranges are smaller, while in poorer habitats, they will range more in search of food. Badgers are known to move multiple miles in a single day and can dig a lot of holes along the way. They are reputed to greatly reduce their activity during the winter in northern climates, but they don’t hibernate, as evidenced by Al Denninger’s photos.
A 1975 Wisconsin study estimated the statewide population between 8,000 and 10,000, but badgers are darn hard to count since they’re mostly active at night and spend most of their time underground. And while their large burrows are easily identified, they often dig many burrows nightly in pursuit of prey, making burrow counting a useless endeavor.
Since so little is known, the WDNR and the University of Wisconsin-Milwaukee teamed up in 2009 to learn more through a study they’re calling the Wisconsin Badger Genetics Project (see badgerresearch.uwm.edu). Researchers are conducting genetic sampling of individual badgers, and as of early fall 2010, have collected 110 samples. Observations reported by citizens are the key to the process. If you see a live badger, a badger carcass, or find a burrow, please e-mail badger@uwm.edu with exact details of the badger’s location. Since the researchers will follow up by visiting the site, photos are particularly helpful so that the researchers don’t go out on wild goose chases. Trail cameras have proven particularly useful for positive identifications.
Badgers have been protected from harvest in Wisconsin since 1955, and thus trapping is illegal.
Detective Work
Kay Lorbiecki in Presque Isle e-mailed the following puzzle: “My Airedale and I just got back from a walk on the lake. We discovered 30 feet from shore the frozen remains of a grouse . . . basically plucked clean (cool feathers) and everything eaten off the bones, but the bones were still attached to each other and included the feathered feet, feathered wings but not the head. Big bird tracks around it and an obvious aerial attack, deep depression where the grouse hit the snow . . . couple of clear hop spaces, then big bird tracks and the arc of a wing in the snow. From the outside edge of the foot track to the wing tip where the feathers flare, it measured 24 inches. I could see the wing leading edge in the snow, then the bend down to the flare of separated feather tips. It happened sometime after 4 p.m. yesterday, but I suspect closer to morning because the resident coyote and fox have not been nosing around for meager scraps. Some kind of owl, do you think? Goshawk?”
Kay did a great job of gathering all the facts and putting them together. So, let’s see if we can analyze the data and reach a likely answer:
1- The wingspread of the bird was around 48 inches. According to Sibley’s Field Guide, the only real suspects, because of their average wingspan, would be as follows: the average wingspread of a barred owl is 42”, a great horned owl 44”, a goshawk 41”. An eagle is 80”, so it’s out of the picture. On occasion in winter, we have a rough-legged hawk or two come down our way – their wingspan is 53”. On rare occasions, we see a snowy or great gray owl – both average a 52” wingspan. It should be noted that other guides differ on the average wingspans, and that average means, well, average. There will be larger birds than the average.
2- The attack appears to have taken place at least at dusk, and most likely at night. According to Tom Erdman, a highly respected expert on raptors, goshawks do not hunt at night – they’re considered pretty blind at night, which is why female goshawks can be taken by nest-raiding fishers in the spring. Still, never say never – goshawks often remain far north in the taiga and have to be able to hunt in low light during the winter. Owls, of course, hunt very well at night.
3- The head was gone. Different raptors have different techniques for killing prey. Most hawks use their feet, get a good grip and squeeze. Owls typically do not bite pieces off of their prey – they simply swallow it whole most of the time. But something large like a grouse, they will have to eat "piece-by-piece." And owls have an established reputation for biting the heads off of prey, but then again, hawks do as well.
4- The attack occurred 30 feet off shore of a lake. Goshawks typically are an interior forest hunter, while owls hunt openings and lakeshores regularly. Still, why was a grouse 30 feet out onto the lake? Could the goshawk have chased it out there?
5- So . . . for me, the evidence overall points to the greatest likelihood of an owl. But which one? There is only one snowy owl so far reported in the state, and no great grays, so the likelihood of one of those is very slim. So, a barred or a great horned? A grouse is a pretty big prey for a barred owl, and a much more common prey species for a great horned owl. So, my best guess based on the evidence . . . a great horned owl ate the grouse.
Sightings
On 1/7, Jean Hall reported seeing several pine grosbeaks at her feeders near the Minocqua Airport. Interestingly, Jean has had evening grosbeaks at her feeders all winter. Evenings are quite uncommon so far this winter.
Jayne Stenstrom in Oneida County sent me photos of wild turkeys that have whitish feathers mixed in among the more common brownish feathers. I asked Bruce Bacon, wildlife manager at the Mercer DNR station, about this, and he said this wasn’t particularly unusual. The males have pale gray flight feathers, but these birds are plainly blessed with more white on them than usual. Bruce noted that breeding the whitest of wild turkeys is how we ended up with white domestic turkeys.
Jane Flanigan in Hazelhurst sent me several fine photographs of an ermine eating suet from her hanging suet bag.
Cherie Smith in Lake Tomahawk sent me a photo of a barred owl that’s hanging around her feeders right outside her kitchen window.
And in Manitowish, we now have 17 pine grosbeaks visiting our feeders regularly. We also had our first common redpolls appear at our feeders on January 1st.
Celestial Events
Look for the full moon on January 19. The moon is near the Pleiades star cluster on the evenings of January 14 and 15; near Gemini’s brightest stars Castor and Pollux on the night of January 18 and near Leo’s brightest star, Regulus, on the night of January 21. Look for Jupiter, the solar system’s largest planet, about half-way up in the southwestern sky during evening twilight. Venus is easily visible in the southeast sky about one hour before sunrise.
Please share your sightings and thoughts: call me at 476-2828, or drop me an e-mail at manitowish@centurytel.net, or snail-mail me at 4245N Hwy. 47, Mercer, WI 54547.
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