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The 117^th Christmas Bird Count season was another one for the books, with a total of 447 counts completed in Canada – just a slight drop from the previous year. Some of these counts have been run for decades, engaging multiple generations in winter birding, while others have recently joined in the tradition. This year, 13 new counts were initiated in Canada, from Spirit River, AB to Baddeck, NS. New or old, CBCs contribute valuable data for assessing bird population health and guiding conservation action.

Compared to the previous season’s unusually warm temperatures, the weather during the 2016-17 count period was more typical of a Canadian winter. Cold snaps and heavy snowfall in some regions resulted in challenging census conditions and lower species totals. There were few lingering migrants, and many freshwater bodies were ice-covered, pushing waterfowl south or coastward. Despite these challenges, Canadian participants rallied in true CBC spirit to tally over three million birds representing an impressive 278 species and over 30 infraspecific forms.

Results by Region

The coastal counts in British Columbia did not disappoint, and this province once more topped the species richness list. Again, Victoria recorded the most species out of all Canadian counts (141), followed by Ladner (136). Among the inland counts, Long Point in Ontario took a turn at the top (112), very closely followed by Blenheim, also in Ontario (111). On the East Coast, Halifax-Dartmouth continued its reign with the highest Atlantic species total (108). All provincial and territorial high counts are listed in Table 1.

On the flip side of the species total spectrum, Arctic Bay in Nunavut tallied three species (Common Raven, Hoary Redpoll, and Rock Ptarmigan): an impressive total, given the few twilight hours available for census in this most northerly CBC circle. Each region in Canada offers different challenges for CBC participants, whether it’s keeping count of thousands of crows flying overhead, trudging through bogs riddled with poison sumac, or, in the North, just trying to find something other than a Common Raven!

Table 1. 117^th Christmas Bird Count Summary / Tableau 1. Résumé du 117^e Recensement des oiseaux de Noël

Most Abundant Species

The 117^th CBC was the ‘Year of the Crow,’ with the American Crow taking top prize as the most abundant species in Canada (336,115). However, this represented a 16% decrease in crow numbers compared to the previous season. The runners-up included European Starling, Canada Goose, Mallard, and Snow Goose, rounding out the top five species. Totals for the 15 most abundant species are listed in Table 2. Snow Geese have continued a dramatic rise, with numbers increasing 12-fold over the past three years, whereas Ring-billed Gulls have dropped back down after spiking in 2015-16. Dark-eyed Junco and Common Redpoll numbers were noticeably lower in 2016-17.

Tableau 2. Espèces les plus abondantes lors des plus récents Recensements des oiseaux de Noël. / Table 2. The most abundant birds on the 2016-17 Christmas Bird Count in Canada, with totals from the two previous counts for comparison.

Interesting Finds

Species considered rare, either for the area or time of year, were documented across the country. Examples included a Red-flanked Bluetail in British Columbia (Comox), and a Pink-footed Goose and Greater White-fronted Goose seen side-by-side in Nova Scotia (Yarmouth). Notable inland finds included a Franklin’s Gull in Alberta (Lethbridge), a Townsend’s Solitaire in Manitoba (Winnipeg), and a Blue-winged Teal in Québec (Sorel-Tracy). Other notables included two species new to the all-time Ontario CBC list: Smith’s Longspur (Long Point) and Western Meadowlark (Woodstock).

The past few years have brought excitingly high numbers of Snowy Owls to southern Canada, sometimes surpassing the 500-count mark. However, this year’s show of snowies was back down to 128 birds, lower than the most recent 15-year average (220). Reasons for impressive southward movements of Snowy Owls are not definitively known, but scientists suggest they might be due to higher than usual nesting success on the northern breeding grounds; more young means more competition for food, which could force birds southward.

Another often-reported trend has been an increased number of American Crows on Canadian CBCs. In 2016-17, American Crow was the most abundant species, with 336,115 individuals counted across Canada; in 1960-61, only 1459 crows were counted. One reason that CBC data are so valuable is that participants diligently record the amount of time they spend searching for birds, which influences how many birds are counted. Nevertheless, even after accounting for search effort, there has been a dramatic increase in American Crow numbers since the 1980s – about a 10-fold increase in the number of crows counted per hour of effort. Many scientists suggest this recent increase is due in part to a positive response to urbanization for roosting, and recovery from population declines related to West Nile virus in the early 2000s.

The Christmas Bird Count offers opportunities for birders of all levels to participate and make meaningful contributions. Whether observing feeder birds through the window, or tromping all day through forests, fields, and wetlands, it all counts. Thank you to all Canadian CBC participants, compilers, and editors for your invaluable contributions.

(Adapted from BirdWatch Canada)