Petroglyphs Count Circle (click to enlarge)
For the 23rd year, local naturalists took stock of wild birds during the annual Petroglyphs Christmas Bird Count (CBC). Most of the (22 km diameter) count circle falls on the southern edge of the exposed Canadian Shield. Agriculture and road development are limited and much of the area remains forested. Bird counting, by sight and sound, is concentrated along county and township roads, ski trails and backyard bird feeders.
The day broke clear and crisp at -20 C. As for most of the past counts, open water was limited to a few very small seeps and some fast sections of streams. Water birds would be scarce at best.
Soon after dusk, Tony Bigg of the Peterborough Field Naturalists crunched the numbers tallied by 17 volunteers who had scattered across six sectors within the circle. Seven other people provided observations from their backyard bird feeders. In the following discussion, the number in parentheses is the average count from the last ten years.
A total of 2779 individuals of 38 species were found, close to the averages of 2773 birds of 34 species. The highest species count, 41, was in 1998 following an unseasonably mild autumn that left our lakes unfrozen and hospitable to five species of waterfowl.
As in past years years, three species - Black-capped Chickadee 859 (998), Blue Jay 437 (306) and Red-breasted Nuthatch 239 (179) - accounted for more than half of birds seen. Some others were present in record numbers. Eighty-nine Rock Pigeons and 93 Mourning Doves broke the previous records of 87 and 27, respectively. Prior to 2002, Wild Turkeys were unknown from the count. Last year, a record 29 were seen and this year, 51. Almost certainly the population will continue to increase. I wonder how and when their number will stabilize. Wild Turkeys - three - were found on yesterday's Algonquin Park Christmas Bird Count for the very first time, evidence of the spread of this species well beyond their introduction sites.
The only water bird seen was a hardy Belted Kingfisher (seen only once before, in 1998) beside a tailings runoff pool below the Indusmin Mine at Nephton. New to the count was a Red-bellied Woodpecker (a Carolinian species steadily marching northward) seen at a suet feeder at the east end of Stony Lake. The ecotonal character of the southern shield is reflected by the juxtaposition of this southern species with Black-backed Woodpecker (a spruce-loving bird of the boreal forest) found today in suitable breeding habitat in Petroglyphs Provincial Park and on the Kawartha Nordic Ski Club trails north of Haultain. Three Gray Jays, another northern species at its southern breeding limit, helped themselves to the hiking snacks of the Petroglyphs Park crew.
Birds of prey were present in small numbers. The observation of three Barred Owls, a resident species, marked the 13th consecutive appearance for this nocturnal hunter. Much rarer, recorded only once before on count day, was a single, day-hunting Great Gray Owl, found by Anne Anthony, Marilyn Taylor and Lynn Smith near Jack Lake. This is the third area sighting in recent weeks, leading some to wonder whether these birds represent the vanguard of a more significant flight. A spectacular winter irruption of Great Grays into Peterborough County last happened in 2004-2005.
Great Gray Owl near Jack Lake courtesy of Anne Anthony
A previous record high of two Goshawks was matched but no other accipiters were seen. A lone Red-tailed Hawk was the only buteo. Red-tails are much commoner in more open country south of the count area.
Veteran CBC participants are always mindful of "misses" - the absence on count day of a species they have come to expect. For species with low populations, misses are a statistical inevitability. If a Sharp-shinned Hawk - perhaps one of only handful in the 400 square km. count area - zigs moments before a human observer zags then the bird will be missed. A notable miss of this year was the sometimes numerous Snow Bunting. Only once before, in 1990, did this visitor from the tundra fail to appear on count day.
Nine species have been seen on every one of the 23 Petroglyphs CBCs. One is the numerous and conspicuous Common Raven. Seven are abundant feeder visitors - Black-capped Chickadees, both nuthatches, Downy and Hairy Woodpeckers, Blue Jay and American Tree Sparrow. The ninth species, the Bald Eagle, is much less common (average of 5) and was very nearly a miss - only a single sighting - in this and five other counts. This year's singleton, a white-headed adult, was spotted by Jerry Ball and Bruce Kidd east of Kasshabog Lake.
Other interesting sightings included 11 Bohemian Waxwings and a single Northern Shrike. Winter finch numbers are highly variable as a result of annual fluctuations in natural food availability in the vast boreal forests of the north. The absence of both crossbill species in odd numbered years since 1999 reflects the cyclic scarcity of spruce and pine cones here and elsewhere. This count turned up 80 White-winged and three Red Cossbills. Rounding out the finch assemblage were 23 Pine Grosbeaks, 12 Purple Finches, 206 Common Redpolls, 75 Pine Siskins, 189 American Goldfinches and two Evening Grosbeaks.
Tony Bigg did an outstanding job of organizing the count and compiling the results. Thanks Tony.
I'm especially grateful to the feeder watchers in my sector: Christine Church, Robin and Roman Miszuk, Doug Charles & Elina Laird.
[The map above is derived from a handy utility, the CBC Base Map Generator, developed by Bird Studies Canada, the organization that oversees CBC activities in Canada.]