The 120th CBC in Minnesota
Cold weather before the 120th Audubon Christmas Bird Count season (2019/2020) resulted in most lakes well frozen before the counts and waterfowl scarce and therefore overall bird numbers reduced. Weather also kept participant numbers down. This count was a down year for most species. Only two species (Sharp-tailed Grouse and Red-headed Woodpeckers) bucked the trend and were found in record numbers. Noteworthy finds included first count records of a Northern Waterthrush on the Bloomington count and Harlan’s subspecies of Red-tailed Hawk on the Excelsior count, as well as a Lark Sparrow on the Mankato count and a Lesser Black-backed Gull on the Duluth count.
Eighty-two of 83 count circles collected and reported data, a slight decrease from last year. One count, Battle Lake, was canceled because of bad weather. Several other counts were rescheduled because of weather. Total participation (1872) was down from the last two years, but just above average, while the 485 feeder watchers were below average for the last five years. Average participation of 22.8 per count was down 6.6% from last year. Twelve counts had more than 40 participants, compared to 15, 11, and 14 over the last three years. Owatonna with a slightly higher turnout than last year, had the most feeder watchers (90), and the most total participants with 97. Henderson, like last year, had 68 feeder watchers No other count had even half that. Four Metro counts had over 60 field surveyors (Excelsior 73, Bloomington 72, Afton 64, and St. Paul 60). The next highest in the state were Minneapolis 46, Duluth 42, and the almost road-less Isabella with 37, some of which were on skis or snowshoes. Nine other counts sent out participants on skis, snowshoes, and/or snowmobiles. In addition, one count had surveyors out on ATVs. The average number of field surveyors was 16.9, compared to 18.1 last year. The average number of feeder watchers was 5.9 compared to 6.26 last year.
While the seasonal snowfall for much of the state was within 6” of historical averages, the 120th count season could still be characterized as snowy, with all but six counts in the south reporting snow on the ground and over half the counts having 6” or more snow depth, in comparison to 14 last year and 11 the year before. Duluth and NE Minnesota had higher than average snowfall, having been hit by a record snowfall in the beginning of December. A second major snowstorm blanketed most of the state at the end of the month. Five counts in the Northeast had 20 more inches of snow. Lake ice formed early due to cold conditions in November. By early December even the larger lakes had frozen over for the season. A slightly higher percentage (84%) of the lakes were frozen this year vs last year (82%).
The total count of birds (208,400) was the second lowest count in the last ten years, only edging out the 117th count year (2016/2017), when there were four fewer count circles. Two years ago, the total of Canada Geese and Mallards counted represented 54% of the total number of birds. Last year they represented 25.5% of the total, and this year they only represented 14.8%. Whereas last year it took five species to account for half of the total bird count, the low Canada Geese numbers this year increase that to six. The species count (127) was the lowest species count in nine years, back when there were only 70 counts, versus this year’s 82.
Only 82 reports (vs 147 last year) were unusual enough or considered difficult IDs of uncommon sightings that they required additional documentation. Only five sightings on count day were not accepted as a result of inadequate or missing documentation. Only one of the non-accepted sightings was a species not found elsewhere in the state. This silent bird, identified as an Eastern Meadowlark, was after review, recorded as an undetermined meadowlark species.
Of the 25 species of waterfowl reported (compared to 27 and 28 species for the last two years) all but two (Common Goldeneye and Common Merganser) were reported at below the ten-year average for the species. The 26,937 Canada Geese, our most common count bird, were 62.4% below the ten-year average, while the 17,073 Mallards, the fourth most common count bird this year, were 31.8% below the ten-year average. Canada Geese were concentrated in large flocks with over 90% found in just nine counts. Mallards were more widely distributed with only 74% in nine locations. The strong numbers of Common Goldeneyes and Common Mergansers were concentrated on the lower St. Croix and Mississippi Rivers with 67.7% and 98.9% found there. Almost 60% of all of the goldeneyes were found on the Red Wing count. The strongly expanding Trumpeter Swans dropped to the lowest numbers in five years. Cackling Geese and Ring-necked Ducks were at their lowest numbers in eight years. No grebes were reported for the first time in over 30 years. American Coot numbers were lower than anything reported for even longer. Three species of water dependent birds (cormorants, pelicans, herons, and kingfishers) were found, but with significantly below average numbers. For the fourth year no cormorants were reported. A notable find was a Belted Kingfisher on the Bluestem Prairie count in Northwestern Minnesota. Water bird numbers demonstrated the obvious relationship: with less open water, there will be fewer water birds.
The most common upland game birds, Wild Turkey and Ring-necked Pheasant, were widely found (80% and 60% of the counts) in above average numbers. Sharp-tailed Grouse numbers were the highest reported in count history, while Spruce Grouse numbers, though small, were the highest in over 20 years. Gray Partridge numbers were very low, while the other grouse reports were inconclusive with high numbers of grouse species not identified.
Bald Eagles were reported in near record numbers, continuing a population growth that is most easily noticed in the winter when the eagles concentrate near water. While they were found on all but two counts, 62% on their numbers were in the one quarter of the counts in southeast Minnesota. The second most common diurnal raptor, the Red-tailed Hawk, was found in over 60% of the counts, but 66% were concentrated in the southeast. The less common hawks and eagles were found in approximately average numbers, with the exceptions of Northern Harrier, the single bird seen in Pipestone and the count week bird Long Prairie, represented that species’ lowest count in over 20 years. The 31 Cooper’s Hawks were the lowest in ten years. A notable find was a first Minnesota count record of a Harlan’s subspecies of Red-tailed Hawk on the Excelsior count.
The numbers of the most common owls, Great-horned and Barred, were below average. Eastern Screech and Great Gray were above average, although neither is common. Snowy Owls were not reported for the first time since 1969. Four other owl species were reported in small numbers. American Kestrels were found in average numbers. Peregrine Falcons and Merlins were reported in small numbers. Notable finds included an American Kestrel in Roseau in the far northwest and a Merlin in Mountain Lake-Windom in the far southwest. Both were outside of the expected range.
Last year’s Herring and Ring-billed gull numbers were characterized as “very low”. This year they were lower, with Herring numbers the third lowest in 20 years, and Ring-bills at the second lowest in 20 years. Uncommon gulls included five Iceland, one Thayer’s during count week, three Glaucous, and only the third Minnesota CBC record of a Lesser Black-backed (in Duluth). All the gulls were reported in seven counts by Lake Superior or near the Mississippi River from Bloomington south.
All three species of doves were reported at lower than average numbers. Even Eurasian Collared-Doves, whose population had exploded five to ten years ago, had settled to lower than the average for the last five years. The common woodpeckers (Red-bellied, Downy, Hairy, Pileated) continue to be found at well above average numbers. Downies and Hairies were found on every count; Pileateds and Red-bellieds each on all but 11 counts. A Red-belly found on the Baudette count in extreme northern Minnesota was reported in one of the last counties where it is not considered regular. All four (plus two count week) Yellow-bellied Sapsucker reports were in counties where they are unexpected in winter. On the Mille Lacs South count the sapsucker was a first-time winter county record. The 98 Red-headed Woodpeckers reported at Cedar Creek Bog plus an additional 12 birds, represented a new record for the Red-heads on the Minnesota CBC, breaking the record of 84 set just two years earlier and attesting to the success of the Red-headed Woodpecker Recovery Program at the Cedar Creek Ecosystem Science Reserve. Their high numbers were attributed to good mast (acorns and nut) availability.
Winter field birds, among the more variable count species, had mixed numbers this year. Horned Lark numbers were about average for the last ten years. Widespread across the state in small numbers, four western counts accounted for almost 60% of the numbers, with the Kensington count in Douglas County, accounting for more than half of that. Lapland Longspurs numbers were way down. Found in small numbers in only 14 counts, they had the lowest numbers in 16 years. Snow Buntings were about average in number. Although found in about half of the counts, seven western counts accounted for over 77% of the numbers.
American Crow numbers were down for a second year. Other corvid numbers were higher, though corvids have yet rebounded from the peaks in the 1990’s as indicated by bird numbers when compared to the number of observers. Blue Jays were found in every count and American Crows missed just two. Canada Jay numbers bounce around on a clear four-to-five year boom and bust cycle and have rebounded from the nadir two years ago. Magpies and ravens are clearly expanding their range over the last ten years and now are found on approximately 20% and 50% of the counts respectively. A hypothesis that Blue Jay winter numbers were dependent on mast availability, like Red-headed Woodpeckers, seems supported by both species well correlated fluctuations over nine of the last the last ten years on the Cedar Creek Bog count.
Northern Shrike numbers were back up from last year, but too low and variable to note any trends. Black-capped Chickadees, both nuthatches, and Brown Creepers were all down from last year’s record high levels. All, but Red-breasted Nuthatches fell below the ten-year average. Black-capped Chickadees were found on all counts, while White-breasted Nuthatches were missed on the same two northern counts that included no crows. Tufted Titmouse numbers were similar to last year’s average tallies, although the number of counts reporting them dropped significantly. Golden-crowned Kinglet numbers rebounded from last year’s low. Only three Carolina Wrens were reported. Unlike last year, all were outside the Metro area. The most unexpected was one on the St. Cloud count.
American Robin and Eastern Bluebird numbers fell from last year’s record or near record levels to less than half the ten-year average. Overwintering robins, which require liquid water, have extremely variable numbers from year to year. However, their winter range is trending toward expansion as they are found on a higher percentage of counts. Only four other thrush family species were recorded vs. last year’s six; again in small numbers. A Hermit Thrush on the Granite Falls count and a Brown Thrasher on the Bemidji count were both first winter county records.
Bohemian Waxwing numbers crashed to the lowest report in 46 years, when there were only half as many counts. Over 85% were found on the Roseau count in far northwestern Minnesota. Cedar Waxwings were unexpectedly also found in lower than average numbers. Although widespread through the state, some of the biggest concentrations were in northeastern Minnesota on three counts along Lake Superior which accounted for about a third of the count. Starlings dropped from last year’s record high to the lowest numbers in more than 20 years. House Sparrows were slightly above average in number. Both species are among the most widespread and numerous species in the state, despite significant decline over the last 30 years. Interestingly, while each was found in about 95% of the counts, the only two counts where they both were not found were the two counts that missed crows and White-breasted Nuthatches.
Dark-eyed Junco and American Tree Sparrow numbers were below average dropping for the third year in a row. They accounted for over 99% of the 11 species of sparrow reported (down from 14 last year). The other species numbers were also mostly low. Notable finds included: a Lark Sparrow on the Mankato count, which was a second-time CBC and second-time winter record for Minnesota, a Spotted Towhee on the Little Falls count, and Chipping Sparrows on the Pelican Rapids and Cottonwood counts.
All of the blackbird species were considerably below average. Besides the Red-winged Blackbirds and Common Grackles, the other four species had between one to three birds. The three cowbirds represented about 5% of the average count for the last 10 years. Two counts accounted for almost 60% of the Red-wings reported.
Northern Cardinals had almost the same numbers as last years. Their population is trending down, although their range is probably stable over the last 20 years. Whereas last year had most finches seeing irruption peaks, this year was a nadir year. All finches were below average, although the southern (American Goldfinch and House Finch) finch counts were not down as much as the others. All the other finches, except Red Crossbills were more than 50 percent below the ten-year average. Pine Grosbeaks were almost absent from Minnesota, found in small numbers on only four counts, the lowest count in over 50 years. For the first time in 20 years, there were fewer Pine Grosbeaks than Evening Grosbeaks. White-winged Crossbills had the lowest count in 20 years.
Only two warblers were reported: a Yellow-rumped Warbler and an unexpected Northern Waterthrush on the Bloomington count, which was a first-time CBC report and second winter record in the state.
A complete table of the results of the 120th Christmas Bird Count in Minnesota (includes data from outside of Minnesota from border counts) is available at: https://moumn.org/CBC/coordinator_yearend_table.php?year=2019&main
For Minnesota only data:
A table showing what sightings were reviewed, what documentation was received, and whether reports were accepted is available for download at: