A Northwoods Almanac for 12/31/10 – 1/ 13/11
by John Bates
Ermines
Pete Esche in Presque Isle sent me a fine picture of an ermine that has been a frequent visitor on his deck throughout December. The picture clearly shows how the ermine has molted from its brown summer pelage into its white winter coat, retaining the black tip on the end of its tail. The black-tipped tail seems an anomaly in its otherwise perfect camouflage; however, one research study found that hawks easily captured fake weasels that had no black-tipped tails. Conversely, the hawks would first hesitate and then attack the tails of the normal black-tipped weasels, presumably mistaking the tails for the ermine’s heads, thus giving the ermines a better chance for escape.
The Northwoods has three species of weasels: the short-tailed (also called the ermine), the long-tailed, and the least. To tell them apart, the short-tailed and the long-tailed weasels have a black-tipped tail, while the least weasel is all white. Long-tails are typically more than a foot in length and their tail is half again as long as their body. Ermines are less than a foot in length and their tail is about a third of their body length, so it works out that long-tailed weasels are about twice as long as ermines.
Still, the long-tailed weasel (Mustela frenata) and the ermine (Mustela erminea) are nearly impossible to distinguish in the field. Genders are easier to tell apart given that the males weigh about twice as much as females.
The Genus Mustela (Weasels and Minks) also includes minks, pine martens, otters, badgers, skunks, wolverines and fishers, but none of these change colors. All mustelids are active in winter, except for the skunk, which becomes semi-dormant in winter, living off its fat.
It’s interesting that when a person is referred to as a “weasel,” it’s a derogatory term usually associated with someone who is gutless and conniving. These slurs are true character assassination, because weasels are bold and confident out of all proportion to their size. They’re considered by some to be the most efficient and fiercest predator on earth, and are well known to attack prey that is often bigger than themselves. Weasels have even been observed to attack snowshoe hares, which weigh at least 5 times as much as they do. One observer also watched a hawk pluck up a weasel, but it soon plummeted from the sky, dead, with the weasel’s teeth sunk into its breast.
Weasels suffer an unduly poor reputation for eating birds when research shows they mostly eat rodents, including rats. They certainly eat some birds, but a 1999 study of least weasels showed that small rodents (mostly voles) constitute 41% of their diet in summer, along with birds, eggs, and insects, while their winter diet is predominantly small rodents. The shape of their bodies tell their evolutionary story - weasels apparently adapted their small, long, sinuous bodies over some four million years expressly for the purpose of following rodents into their burrows.
Weasels are lean, mean, fighting machines particularly in winter because in large part they have no choice. They’re built long and skinny, with very short fur and very small stomachs, and they also put on very little body fat in the winter. These physical attributes combine in winter to make them nearly always cold and hungry, thus their resting metabolism is twice that of other animals their size. They also have to eat more food per day than any other winter-adapted animals. Males consume almost half their own weight every day to stay warm, while females need two-thirds of their own weight daily in order to nurse 8-10 young for three months.
The body-size differential in the genders allows the much larger males to overpower prey too large for the females, while the smaller females can get down burrow holes too narrow for the males, thus making the species as a whole even more efficient hunters.
Weasels hunt at night usually only about 800 feet from the center of their territory investigating every nook and cranny. They’re so active that Richard Conniff in a Smithsonian magazine article perfectly compared their metabolism to “a hip-hop dancer on a caffeine bender.”
Christmas Bird Count
We conducted the 18th annual Manitowish Waters Christmas Bird on 12/19, and we broke our total species count record with 31 species! Now if you live in Madison, where they found 82 species during their count last week, then you will be less than impressed with our total. But Madison is 250 miles south, and the difference in winter conditions between northern and southern Wisconsin is more than amply demonstrated by the vast difference in wintering bird species.
Notable in our count this year were 43 wild turkeys. We never counted a wild turkey until our 2005 count when three appeared, so 43 is quite a jump.
Goldfinches were the one finch species in profusion so far this year – we found 420 of them within our count circle.
We had firsts of a northern cardinal and a white-crowned sparrow. I expect the cardinal numbers to climb steadily in the next decade, but that white-crowned sparrow was either seriously lost, ill, or injured.
Common redpolls showed up in our count (114 of them), even though virtually no one has seen them at their feeders yet. They seem to currently be working white birch trees for their seeds.
Our easiest count of the day occurred when Mary and I were awakened by the calls of two barred owls beneath our window – the only barred owls we got on the count!
Eleven trumpeter swans appear to be spending the winter on the Manitowish River. We first counted wintering trumpeters on the Manitowish back in 1999, and we’ve counted some every year since then. They usually hang out on the open water just before Benson Lake.
We had a great day in Manitowish as well – we counted 16 species out our windows, a record day for us.
Guy David organized the Minoqua count the day before, 12/18, and found 25 species, a very good count for our area as well. Notable on their count, I thought, were the 65 snow buntings they found still hanging around. They’re usually long gone by now.
Perhaps as important as the data we collected were the smiles and camaraderie we all experienced when we met for lunch and shared our mornings successes and disappointments. Good stories always abound, and our mutual enthusiasm is worth every bit of the effort.
Sightings
Judith Bloom in Lake Tomahawk sent photos of a flock of 13 wild turkeys which arrived in their yard on 11/29 and seem to like their ground seed and the shucks from the black sunflower seed. Judith noted, “Once they are done feeding they often hunker down at the far end of our backyard against the hillside and just enjoy the chance to be out of the wind and in the sun if it is shining.”
Sharon Lintereur reported purple finches at their feeders on 12/16, “about a month behind from when they usually come.” Sharon’s doing better than most everyone I know – purple finches are rare so far this winter.
Jane Flanigan in Hazelhurst had an ermine visiting their suet several times during the snow storm on 12/11. She noted, “I think he was determined to take it with him, but wasn't very successful. Entertaining to watch him, but not very photogenic . . . We also have several flying squirrels visiting the sunflower feeder right next to our patio door. They come like clockwork every night.”
A reader in Springstead called on 12/20 to report that a small flock of pine grosbeaks were coming to her platform feeder. Pine grosbeaks have also been very uncommon this winter.
Rich Egdorf in St. Germain had a female red-bellied woodpecker come to his feeder on 12/21. He also has pine grosbeaks coming in.
Al Denninger, who lives between Lake Tomahawk and Rhinelander, told me he has had two pairs of red-bellied woodpeckers nesting on his property for five years now.
On 12/25, we had our first pine grosbeaks appear at our feeder, and on 12/27, a lone bohemian waxwing picked away at the few remaining crabapples left on one of our trees. Later that morning, Mary also spotted a large hawk sitting on the snow beneath our feeder, but it took off almost immediately so she only got a very brief look at it. It was most likely a Cooper’s hawk enjoying either one of the songbirds or some of the mice that often try to grab some seeds from beneath the feeder.
Accessing Earlier Columns from 2010
Over the years, a number of readers have asked me to post my columns so they could read them when they were unable to pick up a copy of the Lakeland Times. Daughter Callie showed me how to create a blog, and though it’s taken me a while to get the hang of it, you can now find my old columns at: www.manitowishriver.blogspot.com.
Celestial Events
January 7 marks the last of the latest sunrises of the year – 7:40 a.m. From here on in, the sun comes up earlier a minute or two every morning until June 20. That’s worth a major cheer!
Best Natural History Books and Outdoor Gear of 2010
Before nearly every Christmas over the last 20 years, I’ve posted a list of books and outdoor gear in this column that I think are worth considering giving as gifts. This year I plain forgot! So, given it’s too late for Christmas, I thought I might solicit your thoughts – what do you think are the best books and/or outdoor gear from 2010 that folks might like to take a gander at? Send me your thoughts via e-mail, and I’ll post the best of the lot.
