A Northwoods Almanac for 1/24 - 2/6/2020
2019 Weather Summary – Hot and Wet
Earth’s warming trend continued in 2019, making it the second-hottest year in NOAA’s (National Oceanic and Atmospheric Administration) 140-year climate record, just behind 2016. The world’s five warmest years have all occurred since 2015 with nine of the 10 warmest years occurring since 2005. It was also the 43rd consecutive year with global land and ocean temperatures, at least nominally, above average. The average temperature across the globe in 2019 was 1.71 degrees F above the 20th-century average.
NASA (National Aeronautics and Space Administration) scientists conducted a separate but similar analysis which concurred with NOAAs ranking. NASA also found that 2010-2019 was the hottest decade ever recorded.
In contrast to the near-record global heat, average temperatures across the contiguous United States made 2019 the 34th warmest year in records that go back 125 years, and the coolest year since 2014. The year closes out a decade that saw nationally averaged temperature alter from intense warmth (including the hottest year in U.S. history, 2012, and the next three warmest years on record, 2015–2017) to more typical values. However, temperatures in the 2010s averaged more than 2°F above the values seen a century earlier, in the 1910s.
Alaska was a different story, experiencing its warmest year on record. At 32.2°F (0.1°C), this was the first time in the nearly 100 years of recordkeeping that the statewide annual average came in above the freezing mark.
Climate change as we all know is all about long-term trends, not one year records. So, looking at trends, the NOAA report shows the number of daily record highs to record lows in the United States has increased every decade since the 1970s. The decadal ratio of record highs to lows comes in at around 2 to 1. That compares to 1.9 to 1 in the 2000s, 1.4 to 1 in the 1990s, and 1.2 to 1 in the 1980s. Thus, the long-term data shows a dramatic increase in record high temperatures compared to record lows throughout the United States. That’s our present, and our future. Read for yourself: https://www.ncei.noaa.gov/news/national-climate-201912.
As for rainfall, according to NOAA’s annual summary, the contiguous United States saw its second wettest year on record in 2019. In five states—Michigan, Minnesota, North and South Dakota, and Wisconsin—2019 was the wettest year on record. Fifteen other states from Nevada to Rhode Island saw a top-ten-wettest year. The nationwide annual average precipitation for 2019 of 34.78” was 4.84 inches above the average and just 0.18” shy of the record-wet year of 1973. However, the last 24 months easily set a record for the wettest two-year calendar span in data going back to 1895.
If we add all the snow we’ve received so far this winter to the record high moisture of 2019, there’s legitimate concern regarding what our water levels will look like this coming spring. Time will tell.
Sightings: Western Meadowlark, Wood Duck, Goldfinches
Karen, in the town of Oma, Iron County, has a western meadowlark coming regularly to her feeders. While a wintering western meadowlark was confirmed in Bayfield County in 2014 and 2016, this is a rare winter sighting for our local area. Western (and eastern) meadowlarks are grassland birds associated with hayfields and pastures where they feed on seeds and insects found on the ground. Our heavy Northwoods winter snowfall usually forces all ground-feeding birds, including meadowlarks, to migrate to far less snowier climes. Why this one chose to visit Oma and remain there is anyone’s guess.
Kris Nelson, who lives year-round on the Manitowish River in Boulder Junction, reported observing a lone female wood duck keeping close to her home throughout the day. She noted, “Our property sits on a wide, lengthy stretch of open water, and she's been feeding and sheltering off the shoreline.” Kris wondered what they might do to help it survive the winter. I wrote back and said that cold isn’t really a major issue for wood ducks, but food is – the woodie should survive if she can find sufficient food. Wood ducks are somewhat unusual in the Northwoods world of ducks because they eat not only aquatic vegetation but quite a lot of tree seeds and grains. They commonly eat corn at people’s feeders in the spring, so I suggested to Kris that she might put corn out for her, or if she could find acorns under the snow, the woodie would love them as well. In a second email, Kris noted that she now has two hen wood ducks.
During our Manitowish Waters Christmas bird count, we found a wood duck wintering on a tiny open creek in Lac du Flambeau, and in speaking with a neighbor there, she said a pair had wintered on the creek the previous year. So, woodies can survive our winters, but why these apparently uninjured individuals chose to stay when they ordinarily migrate south is a mystery.
Birds and Winter – Strategies for Survival
By my very unofficial count, around 155 birds nest in Wisconsin’s Northwoods, but only about 25 of those are permanent residents who remain the winter. The rest, exercising apparent wisdom, are currently sipping pina coladas somewhere well south of here. In fact, out of all of Wisconsin’s 226 confirmed breeding bird species, at least 133 (56%) are neotropical migrants, meaning they winter south of 25° latitude, including both Central and South America.
Historically, northern Wisconsin averages around 5 months of ice cover and snow cover, as well as 8 months of temperatures that dip below freezing. It’s a true test of resilience for birds to balance their caloric checkbook, so that energy-in equals energy-out.
Finding sufficient food to keep the internal furnace stoked is the toughest issue. Birds employ many strategies, one of which, scavenging, is seen every day on roadkills. Our wintering birds have little choice but to be opportunists, and many are quite happy to scavenge a recent kill. Bernd Heinrich, author of Winter World, writes that ravens, for instance, will kill almost any animal they can catch, “but given their high-energy needs, surviving winter for them means feeding on the carcasses of large animals they could never kill. The raven’s carnivore connection is most prominently displayed by association with wolves. Under natural conditions, ravens arrive at and feed on wolf kills within minutes after a pack kills an ungulate . . . By accessing large clumped food resources, ravens can range as far north as their providers—wolves, humans, and polar bears.”
Many of us have seen a recent kill in the woods or along a road, and go back the next day to find innumerable tracks around the carcass. A friend of ours refers to the aftermath gut piles of the annual deer hunt as “coyote Christmas,” but he could call it “chickadee or raven Christmas” as well.
Many people are surprised to learn that chickadees and nuthatches feed on animal remains, too. While around a half of their winter diet is the larvae/pupae of insects and spiders found by probing tree bark, many people have watched chickadees and nuthatches feeding on the fat of dead deer, skunks, and even fish. Hang a deer rib cage in a tree after hunting season, and you’ll feed many a chickadee and nuthatch. Even brown creepers and golden-crowned kinglets are known to forage on fat.
When food is found in abundance, a necessary strategy is to figure out how to store some of it for leaner times. Ravens, as well as blue jays, crows, chickadees and nuthatches, also cache surpluses.
Chickadees cache food mostly in the autumn, hiding food in bark, dead leaves, clusters of conifer needles, knotholes, and even in the ground. Researchers studying their caching have found that chickadees can accurately find their cache sites even after 28 days by using landmark clues and sun compass orientation to find them. Chickadees in harsher northern climes stash more seeds and insects than more southern chickadees, and their hippocampus, the brain region associated with spatial memory, is proportionately larger. In a study comparing Alaskan to Coloradan chickadees, the Alaskan chickadees stored more food, were more accurate and faster in finding their caches, and had larger hippocampi.
Ruffed grouse don’t need to cache food because in 15 minutes they can nip off enough nutrient-rich buds from an aspen or birch tree and store them in their crop to eat later, which lasts them through a day and night. Instead, their more important wintering strategy is to “snow roost” on cold winter days to conserve heat, but also to reduce predation since they are the favorite prey of winter raptors. Heinrich studied ruffed grouse through two Maine winters and found that if there was fluffy snow, ruffed grouse spent most of the day under the snow. He surmised that “their winter problem . . . is not so much to find enough to eat, but rather not to be eaten.”
And then there’s golden-crowned kinglets. These little dynamos have to constantly forage for insects the entire day to make it through a winter night. Heinrich found that they huddle together to stay warm: “On one evening I saw four kinglets disappear into a pine tree. Later that night, with extreme caution and armed with a flashlight, I climbed the tree and spied a four-pack of golden-crowned kinglets huddled together into one bunch, head in and tail out, on a twig. One briefly stuck its head out of the bunch, and quickly retracted it – indicating it was staying warm, and not in cold torpor. Using each other as a heat source, as a means of reducing their own heat loss, is an ingenious strategy, as it alleviated these birds from searching for or returning to a suitable shelter at the end of the day. By traveling as a group and converging to huddle, they were their own shelter instead.”
There are numerous other strategies that individual species employ, each nevertheless a life-risking gamble against the rigors of a northern winter. Heinrich notes, “Surviving winter is not always survival of the biggest and strongest.” Indeed, it’s a matter of thousands of generations struggling to perfect strategies that make the most sense for who they are. Each species has its own story, an ever-evolving one, that we can only try to understand and marvel at.
Celestial Events
The new moon occurs tonight, 1/24. On 1/28, look after dusk for Venus about 4 degrees above the crescent moon. For planet watching in the next two weeks, look before dawn in the southeast dawn for both Jupiter and Mars, and look just after dusk in the west for Venus.
Our days are growing longer by 3 minutes per day as of 1/31. February 4th marks the average midway point between ice-up and ice-out on Foster Lake in Hazelhurst according to Woody Hagge’s 40+ years of data.
Thought for the Week
“The tree which moves some to tears of joy is in the eyes of others only a green thing which stands in the way… As a man is, so he sees.” - William Blake
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