The latest Sea to Sky corridor bird count began in western West Vancouver and the island entrance to Howe Sound (a.k.a. Lower Howe Sound Count) and continued north-easterly through the Coast Mountains, terminating at Ashcroft-Cache Creek. The eight stops along the way provided a unique geographic cross-section of the winter bird lore not done elsewhere in British Columbia, though such a short transect does exist through the Haines Corridor in Alaska-Yukon.
The transect begins with the interface of the Salish Sea to the entrance of a lengthy fiord for this Christmas count.The next stop (Squamish) is at the interface of the fiord head to the high mountains surrounding it. Whistler marks the "pass" through the western ranges of the Coast Mountains and Pemberton-Mt. Currie is in the broad "through" valley between the western and eastern ranges of the Coast Mountains.
Next is D'arcy-Devine on the "pass" through the eastern ranges, and Lillooet sits on the cleft (Fraser Canyon) between the Coast Mountains and the Pavilion Ranges to the east. Upper Hat Creek, a broad elevated inter-montane feature, lies between the western high ridges and eastern foothills of the latter. The transect terminates at the interface of those foothills (Cornwall Range) with the vast Interior Plateau in mid-province.
Climate-wise, it ranges from very moist and very wet, to sub-alpine and alpine, to drier and very dry, over an elevation range of sea level to 2,900 metres. Flora-wise, it passes through maritime and sub-alpine forest to tundra to sagebrush!
This year, 40,088 birds were counted and identified at the eight count centres, the second-highest in nine years of analysis of the transect, or roughly 9,500 above-average.
One hundred and thirty species (four above-average) were identified of the 178 seen over the years at Christmas-time. This includes four new ones added in 2011 (a Rhinoceros auklet in Lower Howe Sound, a Swamp sparrow at Squamish, a Turkey vulture at D'arcy-Devine, and Western tanager at Lillooet). Squamish also noted the first-ever seen Harlan's form (black) of the Red-tailed hawk.
Would you believe that only two species accounted for almost half of the total number of birds counted? Lower Howe Sound tallied a whopping 12,216 Surf scoters (a sea duck) hanging off Bowen and Keats Islands, but also a few around Caulfeild in West Vancouver.
The other big number was 7,816 Pine siskins (a small finch), the majority of which were counted at Whistler!
The other eight species in the top 10 are as follows: Glaucous-winged gulls (2,821 birds), Dark-eyed Oregon junco (1,155), Common raven (1,080), Mallard duck (874), Red crossbill (869), Northwest crow (826), Rock pigeon (750), Bohemian waxwing (743) and Black-capped chickadee (709) — that is, the top 10 account for roughly 75 per cent of all birds seen; 120 species comprise the remaining 25 per cent.