By Karl Ricker
It took the results of eight count centres, from Horseshoe Bay and Keats Island (the Lower Howe Sound CBC) to Ashcroft-Cache Creek but the 2006 Christmas Bird Census in the corridor did reach an aggregate species total typical of a single lower mainland or southern Vancouver Island count.
Yes, there are exceptions: Ladner and Victoria are duking it out at 140-150 species each for top honours in the nation each year. Nonetheless, despite the very inclement Christmas Bird Count season (Dec. 14-Jan. 5), and the cold blasts of November which preceded it, the tally was significant in quality but a little shy on quantity — especially Whistler. The following volumes and species counts were garnered at the eight centres (from south to north): Lower Howe Sound: 12,736 birds, 80 spp; Squamish: 10,202 birds, 76 spp; Whistler: 1,067 birds, 49 spp; Pemberton-Mt. Currie: 2,550 birds, 60 spp; D’Arcy-Devine: 795 birds, 54 spp; Lillooet: 3,409 birds, 58 spp; Hat Creek: 382 birds, 31 spp; and Ashcroft-Cache Creek: 1,848 birds, 43 spp. Species counts, by the way, include birds seen in count week, which for Whistler amounted to 8 of 49 tallied.
The survey covers a transect from the maritime mountain front through the entire breadth of the Coast and Cascade Mountains to the rain-shadow western edge of the Interior Plateau. There are no other transects of such calibre through a mountain system elsewhere in Canada, or Washington and Oregon, but there are two in Alaska and several in California–Nevada.
Over such a breadth a diverse array of birds is to be expected, from sea birds of the ocean environment to raptors and upland birds of the interior dry belt. Nonetheless, the following species were found in all eight counts: Great blue heron (a high of 21 at Lower Howe Sound); Bald eagle (1,625 at Squamish); Northern flicker (67 at Lower Howe Sound); Raven (268 at Lillooet); Steller’s jay (150 at Pemberton); Black-capped chickadee (276 at Squamish); Red-breasted nuthatch (51 at Lower Howe Sound); American dipper (90 at Squamish); Starling (351 at Squamish); and Song sparrow (257 at Squamish). Yes, Whistler did not have a big contribution this year on the volume of any species.
On the opposite end of the scale every count had at least one unique species, not seen elsewhere. Not unexpected there were 22 “uniques” at Lower Howe Sound (sea ducks, shore birds, but also Anna’s hummingbird, Hermit thrush and Band-tailed pigeons), 15 at Squamish (more sea ducks, Barred owl and an out-of-habitat Gray-crowned rosy finch), a surprising five at Whistler (Gadwall duck, Spruce grouse, Western gull, White-tailed ptarmigan and Three-toed woodpecker — finally!), only two at Pemberton (a flock of Tundra swans, and a Brown-headed cowbird), one at D’Arcy (Merlin), four at Lillooet (Wilson’s snipe, Morning dove, Pygmy nuthatch and Red crossbill), a single one at Hat Creek (American tree sparrow) and a lone one at Ashcroft (Sharp-tailed grouse). The compiler for Hat Creek, Ken Wright, responded by saying that he was glad to be able to contribute something new to the corridor count!