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Ten years of Sea to Sky Christmas bird counts

The numbers, the species, the special sightings

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As usual, it takes a while to post all of the Christmas Bird Count data for the Sea to Sky corridor. This area has a south-west anchor at Lower Howe Sound (Horseshoe Bay and offshore islands), and proceeds into the mountains at Squamish, Whistler, Pemberton-Mt. Currie, D'arcy-Devine to Lillooet and then over the Pavilion Ranges through Hat Creek to a north-east anchor at Ashcroft-Cache Creek on the leeward side of all mountainous terrain.

This year, Squamish led with 10,894 birds counted and 87 species identified, surpassing the usual leader, Lower Howe Sound, which had half that many birds and only 68 species. In fact, Pemberton-Mt. Currie spotted 73 species but with only 2,508 birds counted, and barely eking out Lillooet with 69 species and 2,650 birds.

It is a toss-up whether Whistler, with 58 species and only 859 birds, or Hat Creek, with 28 species, but 1,261 birds, is at the bottom of the pile.

D'arcy, despite a 40 centimetre snowfall on count day, was better than either with 49 species and 1,495 birds counted.

Other than Lower Howe Sound, all other counts reached average, to above-average species counts. All told, 30,416 birds were tallied, with 131 species identified. The decadal averages are 127 species identified and 30,130 birds tallied, signifying that the 2012 Christmas season for the corridor was average, the extra four species being attributed to birds never seen before; a Ruddy duck at D'arcy, a Sora rail at Lillooet, a flycatcher (Phoebe?) at Ashcroft, and Snowy owls at Squamish and Whistler. There are always surprises, and Lillooet usually has the best ones, repeatedly, every year!

For 2012, the following species were seen at all eight count localities: Mallard ducks, Merlin falcons, Common ravens (as expected), Black-capped chickadees, American dippers and Song Sparrows. Usually, Downy and Hairy woodpeckers are seen at all sites, but this year Ashcroft failed to deliver. There are 14 other species which were seen at seven of the eight sites, the most significant being a Townsend's solitaire (a thrush) and Common redpoll — a bird closely related to the Pine siskin, which was Whistler's most numerous species last year (4,655), but this year weighed in at only 186 seen. However, most of the redpolls were to the east with three- figure counts at D'arcy, Lillooet, Hat Creek and Ashcroft.

In descending order, the most abundant species were: Glaucous-winged gulls (especially at Squamish), Pine siskins (again, Squamish and Lower Howe Sound), Dark-eyed Oregon Junco (Pemberton, well-endowed), Bohemian waxwing (a Hat Creek specialty), Common raven (lots at Ashcroft), Starling (again, Ashcroft), Rock pigeon (and again, Ashcroft), Robin (record numbers at Lillooet) and Bald eagle (Squamish).

Alas, Whistler topped all other localities with: Trumpeter swan (20), Greater scaup duck (25), Pied-billed grebe (3), Steller's jay (75), and Gray jay or Whiskeyjack (26).

Notwithstanding, there were also 10-year high counts on Eared grebe, Greater White-fronted geese, Northern pintail (duck), Greater scaup (duck), Merlin (falcon), Eurasian Collared-dove (an invasive, expanding its range rapidly in North America), Red-winged blackbird, Common redpoll and ties to previous high counts by Cooper's hawk, Red-tailed hawk and California gulls. There were also way above-average tallies on Lesser scaup, Cassin's finch and Evening grosbeak (a species of concern).

And as for the lows, Black turnstones, Red-breasted Sapsucker, Steller's jay, Black-capped chickadee, Pacific wren and Ruby-crowned kinglets nose-dived in numbers and Surf birds (a Lower Howe Sound in habitant) drew a zilch!

As usual, some species are seen at only one count centre and not at any of the others.

Lower Howe Sound, in the mild marine habitat, was the usual leader in harbouring exclusive species. But, this year, Squamish, despite its foul weather, managed 12 exclusives and 32 species with the highest tallies in the region to lead the way, followed by: Lower Howe Sound, with 10 exclusives and 27 high counts; Lillooet, with six only's and 18 highs; Pemberton-Mt. Currie, with four exclusives and 11 highs; Whistler, with three exclusives and eight high tallies; Ashcroft-Cache Creek, with only one exclusive and eight highest tallies; Hat Creek, with one not seen anywhere else and four high tallies; and D'arcy-Devine with the only Ruddy duck and two other high tallies. The high tally species at Whistler were Trumpeter swans (20), Greater scaup (26), Pied-billed grebe (three), Steller's jay (75), Gray jay (26) and the only sightings of Tundra swan (one), White-winged scoter (one) and White-tailed ptarmigan.

Were there any obvious regional trends in numbers of birds sighted for a given species?

There are a few obvious ones: from the marine zone to the interior, there were decreasing numbers, more or less, of Ring-necked ducks, Hooded mergansers (duck), Common loons, Great Blue herons, Glaucous-winged gulls, Kingfishers, Steller's jays, Northwest crows, Black-capped and Chestnut-backed chickadees, Pacific wrens, Golden-crowned kinglets, Varied thrush and Fox sparrows; but, conversely, from the interior to the coast, there were decreasing numbers of Rock pigeons, Eurasian Collared-doves, American crows, Bohemian waxwings, Common redpolls and possibly Townsend's solitaires (an unusually high of 85 at Hat Creek).

And there were many other strictly marine species (e.g. Black turnstone and Oystercatcher) and a few dry belt-only species (e.g. magpies). There were also a few mountain-only species, found between Whistler and Hat Creek, which descend to valley floors during cold winter months: Mountain chickadees, Gray jay, Pine grosbeak, and several finch species. This year, White-winged crossbills provided surprises throughout south-western B.C., but we didn't see any at Whistler.

Despite two extreme weather events, which affected the Squamish and D'arcy-Devine counts, the Christmas census for 2012 was successful.

Over the 10 years of corridor surveys, 180 species have been identified. Several of those are "once-only's," never to be seen again in years to come because they were either out of range wanderers (e.g. Western Scrub jay at Squamish, 2004), or out of season lingerers (e.g. Osprey at Squamish in 2005).

The 131 species tallied this past season equates to 72.8 per cent seen of the current list seen over the last 10 years. Not bad at all, and it could have been a little better, perhaps, if the Lower Howe Sound count would have been conducted a few days before Christmas instead of its scheduled post-New Year's January 5th date.

It is well-known that the number of species to be seen diminishes in January for most of Canada, which is certainly the case at Whistler.