[Tweeters] Seattle Christmas Bird Count 29 Dec 2018 - summary of results

Matt Bartels mattxyz at earthlink.net
Sun Jan 6 16:47:33 PST 2019

Tweeters -
We’ll have a complete write-up for every species total and the like up on the Seattle Audubon website before long, but for now here’s a summary of last weekend’s Seattle CBC, the 90th iteration of the Seattle circle:

2018 Seattle Christmas Bird Count
29 December 2018

121 species tallied (count day + count week)
Count day: 117species
Count week: 4 additional species
Individual birds: 46,748 birds
Observers: 314 [227 in field + 87 feeder watchers]

The 2018 Seattle Christmas Bird count was held on a windy, then rainy day – intrepid CBC-ers persisted, though, and found all the birds willing to be found. Our total of over forty-six thousand birds was lower than average, about the sixth best year in the past decade. Not amazing, but also not as low as it might have seemed during the day. The count-day species total of 117 was the lowest since 2003, and even when we add in four count-week birds, our total of 121 species was the lowest in over a decade. The effects of the weather probably overwhelm most efforts to draw trend conclusions out of the results, but it is interesting nevertheless to see how this year compares with others….

We continue to have strong participation numbers – this was our third year with over 300 participants. 87 feeder watchers contributed 2392 birds, about 5% of the total. On the bird front: One species was new for the count: Eurasian Collared-Dove. Considering that over 5700 Eurasian Collared-Doves were reported in Washington CBCs last year, and given that we were one of the last counts in the state to finally add this species to their circle, this is one of the least surprising new species to report. I think in Washington now the only counts without this species are the North Cascades count in the mountains and the ferry trip from Anacortes to Sidney.

A flock of 30 Barn Swallows at the Montlake Fill was another highlight – This species has only appeared on three previous counts (along with two count week sightings), and the previous high count was 2. Other notable birds included a feeder-watch Western Tanager [6th sighting in the ‘modern CBC era’], a count-week Clark’s Grebe [5th ever for the count], and a count-week Townsend’s Solitaire [6 of the last 10 counts, but only 10 times total in the last 50 years].

The bigger story though were low numbers for many species – At least partially due to the weather keeping the boat party from their usual route, almost all saltwater species showed very low totals including ducks, grebes, alcids, most gulls and loons. On land, the results were more mixed, as the more detailed discussion below will note, with many species lower than average, but some surprisingly high counts as well.

Notable Misses:
Four species were only picked up as count week birds: Snow Goose, Clark’s Grebe, Bonaparte’s Gull and Townsend’s Solitaire. In addition, species missed entirely for the count circle that have been seen in half or more of recent counts included: Redhead, White-winged Scoter (our first year missing them since the 1920s!), California Quail, Marbled Murrelet, Great Horned Owl, Evening Grosbeak and Red Crossbill.

Record high counts:
For the modern period (1972-present), high counts were recorded for five species: Wood Duck (121), American Wigeon (4076), Eurasian Collared-Dove (15), Barn Swallow (30), and Yellow-rumped Warbler (465, more than 150 higher than the previous best). A few other species came close to their highest marks: Anna’s Hummingbird (3rd highest total at 456), Chestnut-backed Chickadee (3rd best ever, 385), American Goldfinch (2nd best ever, 731), White-throated Sparrow (3 seen, tied for 3rd best ever), White-crowned Sparrow (2nd best ever, 105), and Dark-eyed Junco (3rd best ever, 1732).

[numbers in brackets indicate the total number seen and the percentage as a ratio of the 10-year average on the count]

Ducks and geese:
As with recent years, the trend in general was for dabbling ducks to be doing about average and saltwater ducks to continue their seeming local decline. Along with the previously mentioned Wood Duck [121, 364%] and American Wigeon [4076, 181%], several other ducks were seen at higher than average numbers, including: Gadwall [674, 109%], Mallard [1700, 135%] and Green-winged Teal [187, 175%]. At the other end, Greater Scaup [48, 16%], Lesser Scaup [47, 13% - record low], Harlequin Duck [24, 38%] and Surf Scoter [173, 20% - record low] were some of the species that were well below their previous averages.

Grebes and pigeons:
Pied-billed Grebe were again seen in good numbers [211, 111%], but all other grebe species were low: Horned Grebe [187, 60%], Red-necked Grebe [47, 42%], Eared Grebe [1, 60%], Western Grebe [119, 16% - record low]. Rock Pigeon numbers were down [1291, 59%], but Band-tailed Pigeon did alright [70, 133%] and the previously mentioned Eurasian Collared Doves [15] were good to add to our count circle.

Alcids, loons, cormorants:
Alcids were pretty elusive this year. In addition to missing Marbled Murrelet, the three species seen all came in at less than half their recent average: Common Murre [16, 22%], Pigeon Guillemot [21, 39%], Rhinoceros Auklet [24, 43%]. The three loon species seen were similarly found in below-average numbers: Red-throated Loon [12, 41%], Pacific Loon [19, 85%], Common Loon [5, 41%]. The story for cormorants was mixed: Brandt’s Cormorant [103, 46%], Double-crested Cormorant [840, 117%], Pelagic Cormorant [35, 77%].

We found 8 species of gull, and the numbers were not bad: A few came in high: Mew Gull [1373, 115%], California Gull [36, 130%]. Others were low: Ring-billed Gull [146, 69%], Western Gull, Iceland & Herring [each with 3 seen, respectively 38%, 81% and 86% of their average]. Though birds labelled Glaucous-winged Gull were well down [732, 54%], if you combine that species with the Western x Glaucous-winged Gull numbers [1297, 370%], the combined total of 2029 is 119% of the merged average. The changed proportions were likely somewhat influenced by more guidance advising caution in assuming all large gulls were pure Glaucous-winged.

Hawks and owls:
Other than Bald Eagle [112, 136%], other raptors came in at low numbers: Sharp-shinned Hawk [4, 39%], Cooper’s Hawk [14, 63%], and Red-tailed Hawk [27, 73%]. Other than missing Great Horned Owl, we did decently with owls given the wind and rain, finding a dozen owls of four species: Barn Owl [3, 100%], Western Screech-Owl [1, 59%], Barred Owl [6, 81%] and N. Saw-whet Owl [2, 125%].

Corvids were a mixed bag: Those seen at higher than usual rates were California Scrub-Jay [12, 126%] and Common Raven [6, 135%], while Steller’s Jay [89, 49%] and American Crow [5574, 64%] were low. This marks the fewest Steller’s Jays found in 20 years, and the crow numbers continue a trend of being much lower than the years near the early 2000s when a crow roost was inside the count circle.

Several passerine species were found at relatively normal rates despite the excuse of the weather: Black-capped Chickadee [1678, 102%], Bushtit [1073, 112%], Golden-crowned Kinglet [898, 93%], American Robin [2601, 96%] and House Finch [657, 91%].

Others were notably low this year, presumably just because of transient factors like the day’s weather or the season’s weather: Red-breasted Nuthatch [91, 67%], Pacific Wren [122, 64%], Ruby-crowned Kinglet [204, 58%], Varied Thrush [68, 56%] and Townsend’s Warbler [9, 35%]. Others were low but seemed to be confirming a general trajectory of lower numbers for the count: House Sparrow [204, 48%], Purple Finch [3, 20%], and Red-winged Blackbird [82, 58%, perhaps following Brewer’s Blackbirds out of the circle?]

There were a few passerines found at higher than usual numbers too though! These included Hutton’s Vireo [13, 289%], Chestnut-backed Chickadees [385, 123%], Cedar Waxwing [122, 129%] and American Goldfinch [731, 156%],

Sparrows: Other than the notably high counts of White-throated Sparrow, White-crowned Sparrow and Dark-eyed Junco mentioned earlier, all other sparrow species were low this year, most notably: Spotted Towhee [226, 80%], Fox Sparrow [45, 30%], Song Sparrow [618, 78%], Lincoln’s Sparrow [1, 6%!!].

There might be a few tweaks as the final bits and pieces come in, but that about covers it.

Thanks to everyone who participated and made this another great count.

Matt Bartels
Seattle CBC Compiler
Seattle, WA
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