Oil on Panel - 4 x 4 inches
For the first time in ten winters at my home in Duluth, MN, American Tree Sparrows have stuck around all season, and that is most likely because we had very little snowfall. Just how little? Before the snowstorm of March 25th, Duluth was over 40 inches below normal, giving these seed-loving birds lots of areas to forage from bare ground, month after month.
In addition to a generally snowless winter, Duluth’s just experienced its second warmest winter on record. In all likelihood, the record would have fallen had the current weather station’s locale been in the same spot as it was in 1877-78, the winter that still covets first place. Currently, official temperatures are recorded at the Duluth International Airport, but it is approximately 5 miles further inland from the old weather station on Superior Street, just 1000 feet from Lake Superior. If anyone took temperature records at the old location, it would be interesting to know if the record was broken. It’s always nice to compare apples to apples.
During more normal winters (is there such a thing as normal anymore?), American Tree Sparrows aren't around. Big seed eaters, if the ground is covered with snow, they’ll typically stay further south. However, this is one bird that has a tendency to flock to urban areas during cold spells. Urban areas can be up to 10° F (6° C) warmer, and can provide this species with much needed warmth to survive. Known as the urban heat island effect where roads, buildings, and dense concentrations of similar materials absorb and retain heat, other birds like Carolina Wrens, Northern Cardinals and House Finches benefit from this scenario as well. Just like American Tree Sparrows, these birds are less tolerant of cold temperatures compared to Downy Woodpeckers and Black-capped Chickadees; but when Duluth is covered in snow for months at a time, regardless of its temperature, American Tree Sparrows are likely to stay away due to its food source being inaccessible.
So, consider this an update to my blog entry from Feb. 9th. Based on my most recent research, it appears the lack of snow probably had more to do with the American Tree Sparrows’ presence than this winter's warm temperatures.
If your neck isn't too sore from viewing today's solar eclipse, keep your eyes on the skies. The migration has begun. Yard sightings include the following: American Robins, Common Grackles, Red-winged Blackbirds, Mourning Dove, Fox Sparrows, Purple Finches, Yellow-bellied Sapsucker (heard), hawk (species unknown), and soaring Bald Eagles migrating north. Our resident mallards have returned. Hoards of Common Redpolls and Dark-eyed Juncos are common each April and this year is no exception.
Enjoy the migration everyone. Stay wild !
Devokaitis, M. (2021, Winter). Feeders in Urban Areas May Provide Refuge for Wintering Birds. Living Bird, 40(1), 60.
Latimer CE, Zuckerberg B. Habitat loss and thermal tolerances influence the sensitivity of resident bird populations to winter weather at regional scales. J Anim Ecol. 2021; 90: 317–329. https://doi.org/10.1111/1365-2656.13332
Sundgaard, S. (2024, Feb. 13). A break in the snow drought? First measurable snowfall in weeks coming. Minnesota Public Radio. https://www.mprnews.org/story/2024/02/13/a-break-in-the-snow-drought-first-measurable-snowfall-in-weeks-coming
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