A Northwoods Almanac for January 19 – Feb. 1, 2024 by John Bates
Great Lakes Ice Cover
On New Year’s Day, the Great Lakes had the smallest amount of ice cover in the past 50 years. Only 0.35% of the Great Lakes was covered with ice, far below the roughly 9% that is typical for this point in the winter.
According to a NOAA analysis, between 1973 and 2017, the average Great Lakes ice cover dropped by about 70 percent. Cumulatively, researchers have also recorded as many as 46 fewer days per season of frozen ice on the Great Lakes – defined as a day when at least 5 percent of the lake’s surface had ice cover – with the most significant decreases in Lakes Ontario and Superior.
However, year-to-year variability can happen even during the decline. The lowest winter ice cover came in 2002, when the maximum coverage for the season was 11.8%. But just five years ago, in 2019, the maximum ice cover was 81%, among the highest ever.
So, we’ll see how the winter commences. Climate is the long haul, weather the short haul. We’re getting some colder weather now, but unless we get some continuously very cold weather in the next few months, we may be on course for a record low year climatically.
Northern Shrike
Over the last few weeks, we’ve had a northern shrike stalking our feeders in search of its next songbird meal. At first, we’re always excited to see a shrike, but that’s short-lived. Shrikes specialize in capturing and eating songbirds, and thus they make life for our feeder birds one of constant anxiety.
We were eating lunch recently, and I wondered how it would feel to know something or someone was lurking nearby ready to kill one of us – not the most peaceful dining experience, I imagine.
In North America, northern shrikes breed from Labrador to Alaska, living on the natural edge between boreal forest and open tundra. Many, but not all, individuals typically migrate south to southern Canada and northern United States during late fall and early winter.
They’re known for impaling their prey on thorns, barbed-wire fences or wedging them in forks of branchlets, and thus have earned the nickname “butcher bird” for their slow dismantling of prey. A shrike’s small feet don’t allow it to properly grip prey, so it skewers its food to hold it in place while eating. One author refers to shrikes as “a veritable ornithological Vlad the Impaler.” The bird’s Latin name, Lanius excubitor (“watchful butcher”), speaks to this.
 |
| Northern shrike capturing a pine siskin, photo by Bev Engstrom |
A shrike sometimes kills several birds in a brief period, impaling them near one another on a thorn, which is a form of caching, and not much different than our freezing leftovers.
We see “our” bird most commonly surveying the landscape from a perch at the very top of a silver maple, where its rather small size – like a robin – appears innocuous. However, if a flock of finches picks up, they will actively pursue them in flight and even into thick bushes.
The blue jays around our feeders seem unperturbed, but shrikes are known to occasionally take down birds larger than themselves, including robins, jays, and doves, so perhaps the jays need to read the literature more carefully.
Although they’re not noted for their song, over the years we’ve heard them occasionally sing, and apparently this is a ruse to get songbirds to wander over to hear who’s singing, and then the shrike can nail one.
The literature says shrikes have the ability to spot motionless birds “frozen” on branches and to capture them before they move, so this is not good news for our hairy and downy woodpeckers who commonly use this defense strategy.
Their winter diet also includes small mammals like voles, shrews, and mice who like to scavenge for seeds under our feeders. They’re even reported to infrequently feed on carrion.
We wonder how many birds or mice they need to eat per day to survive, but no one seems to know. Their success rate in capturing prey is quite low, so maybe they’re not capable of decimating our local flocks. We’re certainly hoping this is the case and will be watching.
Red and White-winged Crossbills, and the Need for Seeds
Reports of good numbers of red and white-winged crossbills have been steadily coming in over much of North America, in particular out West. Crossbills have evolved a (wait for it . . .) crossed bill that is perfect for prying open and extracting seeds from open cones of spruces, pines, and other conifers. According to one researcher, white-winged crossbills can extract and consume 3,000 conifer seeds in a day.
 |
| Red crossbills, photo by Mark Westphal |
This factoid led me to wonder just how many seeds are in a given cone of our various conifer species, and thus how many cones a crossbill may need to find on any given winter day.
So, here’s a sampling. For white pines, the Wisconsin Silvicultural Handbook (WSH) says the number of good seeds per cone varies from 0 to 73, with good crop years occurring every 3 to 5 years. So, for discussion’s sake, let’s say a white pine produces 50 seeds per cone in a good year, which means a single crossbill would need 60 cones a day, assuming they need that many seeds every day. Crossbills usually flock together, so a multiplier would need to be assigned here.
Red pine trees produce a mean of 45 seeds per cone in a good seed year, which means a crossbill would need 66 cones a day. Each tree, BTW, produces 50 to 200 cones or about 1,000 to 4,000 viable seeds/tree, according to the US Forest Service (USFS). Good seed crops are produced every 3 to 7 years, with bumper crops only every 10 to 12 years (WSH).
White spruce cones average 140 seeds each, so a single crossbill would need about 20 cones a day. These seeds are extremely lightweight averaging about 240,000 seeds per pound. Usually the seeds are blown about 330 feet, but dispersal in excess of 1000 feet is possible from mature trees. A good seed crop years occurs every 2 to 4 years (WSH).
For eastern hemlocks, I couldn’t find a source to give me a direct answer for their tiny cones, but the USFS says, “In one locality, only 2.1 viable seeds were produced per cone, 2.2 were destroyed by insects, and the remaining 8.0 seeds were empty.” Let’s just say a hemlock cone may average about 10 seeds per cone, so a crossbill working on a hemlock tree would need 300 cones per day.
How about balsam firs? They produce 134 seeds per cone (USFS), which means a crossbill would need 22 cones per day. Good seed crops occur every 2 to 4 years.
Enough statistics – the take away is that crossbills need large stands of cone-bearing conifers to make it through a winter. Thus, they often have to travel long distances to find good stands. Some crossbills have been observed to move three times in a year over a combined distance of 2,000 miles, so they are true nomads following the cone crops.
What makes them even more unique is that if the cone crop is good, they’ll breed, no matter the season. Both species are known to have nested in every month of the year, regardless of the weather.
Good News in 2023
Americans purchased 1 million fully electric vehicles in 2023, a record, according to a report from Bloomberg New Energy Finance. Electric vehicles accounted for about 8% of all new vehicles sales in the US during the first half of 2023.
In China, EVs accounted for 19% of all vehicle sales, and worldwide, they made up 15% of new passenger vehicle sales. EV sales in Europe were up 47% in the first nine months of 2023.
China, the world’s biggest climate polluter, has made lightning advances in renewables, with the country set to shatter its wind and solar target five years early. China’s solar capacity is now greater than the rest of the world’s nations combined.
It can’t be ignored, however, that China also ramped up its coal production in 2023, turning to fossil fuel as devastating heat waves increased energy demand for air conditioning, and as persistent drought in the country’s south impacted hydroelectric supplies, which are reliant on sufficient rainfall.
It’s a problem. Climate change keeps amping up the need for more renewable energy sources, and already we’re not moving fast enough to meet today’s energy requirements, much less the future needs caused by a warming climate.
Solar and Wind Energy Expected to Overtake Coal This Year
Still, in much of the U.S., it’s already cheaper to build and operate an entirely new solar or wind plant than to continue operating an existing coal-fired plant. The electricity generated by wind and solar combined is expected to surpass coal-fired electricity sometime this year, according to forecasts from the independent U.S. Energy Information Administration: “We expect that the 23 gigawatts (GW) in 2023 and 37 GW in 2024 of new solar capacity scheduled to come online will help U.S. solar generation grow by 39% in 2024. We expect solar and wind generation together in 2024 to overtake electric power generation from coal for the first year ever, exceeding coal by nearly 90 billion kilowatt hours.”
Snowy Owl-less Winter So Far
Very few snowy owls have been seen in WI or most of the lower 48 this year. So far, there have been only a handful of snowy owls reported from the western Great Lakes east to New England.
You have to go back to the early winter of 2010 to find a year with so few snowy owl reports in eastern and central North America. The Audubon Christmas Bird Count (CBC) tallied just five snowy owls continent-wide that year.
Off-years like this one are part of the periodic boom and bust in snowy owl breeding ecology. Occasionally they suffer from a poor lemming year, their main prey, and thus a poor breeding season for the owls results, with fewer young birds coming south.
The unusually mild winter weather so far may also be conspiring to keep owls farther north than normal. It’s also possible that the effects of highly pathogenic avian influenza (HPAI), which has hit snowy owls fairly hard, could be a cause.
Celestial Events
Our days are growing longer now by more than 2 minutes per day.
The next two weeks or so (Jan. 20 to Feb. 5) are when we experience, on average, the coldest low temperatures of the year.
The full moon – Native American names include the “Frost in the Teepee” or The Wolf” or “The Great Spirit” moon – occurs on 1/25.
After dusk, look for Jupiter high in the south and Saturn very low in the southwest. Before dawn, look for Venus low in the southeast and Mars rising in the southeast.
Quote for the Week
“Right now, everyone is looking for sources of guidance, resilience, and beauty in a world that’s turned upside down. We’re looking for those who can speak to our core need to respect and honor our relationships with one another and with the living world.” - Curt Meine
Please share your outdoor sightings and thoughts: e-mail me at manitowish@centurytel.net, call 715-476-2828, snail-mail at 4245N State Highway 47, Mercer, WI, or see my blog at www.manitowishriver.blogspot.com
