Pine Grosbeaks - first of this season

Three of the six Pine Grosbeaks we saw today.
After watching the Northern Hawk Owl this morning, we returned home to find six Pine Grosbeaks at the bottom of our drive. These were the first we've seen in central Ontario this season and, like the Evening Grosbeaks, weren't expected given the this year's bumper crop of Mountain Ash fruit north of Lake Superior.
Ron Pittaway's Winter Finch Forecast, 2008 provides a thorough discussion of the distribution of irruptive winter finches in Ontario.
Male Pine Grosbeak in a Mountain Ash tree, we observed on the Marathon (Thunder Bay District), Ontario, Christmas Bird Count on December 21.

Bald Eagles

We see them every month of the year. Numbers seem to increase during the winter when they can be often be seen at our local landfill sites. This pair of birds flew up from the roadside - perhaps there was a roadkill off the shoulder, beyond my sight.

Cerulean Warblers in cottage country

Courtesy of Lana Hays
We were delighted to find at least two Cerulean Warblers (Dendroica cerulea) singing in the hardwood forest less than a kilometre from our back door. I recorded some sounds from the first bird we found singing on May 21, 2007. On May 23, we found two males countersinging 300 m from where we made our May 21 observation. The video begins and ends with a Cerulean song. There's some Red-eyed Vireo (Vireo olivaceus) chatter in between.

This follows our observation of a single Cerulean Warbler in the same woodlot in May last year. We don't know whether they're actually breeding but the habitat - mature, mesic upland hardwood forest - corresponds to that utilized by well-studied breeding populations at the Queen's University Biological Station, 200 km to the east. We'll monitor the site over the next few weeks for signs of breeding.

The Cerulean Warbler is a species of special concern* in Canada, where the population is estimated to be only 500-1000 breeding pairs. Some populations in the United States have experienced precipitous declines. One of the threats to the Cerulean Warbler is the destruction of the tropical forests in which it, and a suite of other Neotropical migrant songbirds, spend the winter. This is one of the reasons we choose to buy shade grown coffee [on-line] from Birds and Beans in Toronto.

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Update - June 3, 2007. This species isn't unknown from the Kawartha Lakes. In the late 1990's, Cerulean Warblers were found breeding near Buckhorn, about 20 km east of us. As far as we know, they haven't been found there in recent years. We visited the area two days ago and located two singing Ceruleans as we drove slowly and listened through the open window of our vehicle, during the middle of the day. No doubt, there are more in the area.

The forests are similar to those near our home - second growth with a canopy largely enclosed by even-aged sugar maple. Just over a century ago, these lands were cleared for farmland; however, the soils are thin along the edge of the Canadian Shield and much of the land proved not to be arable. Succeeding generations from the pioneering families abandoned these farm fields allowing the forests to regenerate. Cerulean Warbler populations along the southern edge of the Shield appear to be benefiting, faring much better than those in the core of their range in the United States.

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* Special Concern - A species of special concern because of characteristics that make it particularly sensitive to human activities or natural events.

COSEWIC. 2003. COSEWIC assessment and update status report on the Cerulean Warbler Dendroica cerulea in Canada. Committee on the Status of Endangered Wildlife in Canada. Ottawa. vii + 25 pp. Available here.

Hamel, P. B. 2000. Cerulean Warbler (Dendroica cerulea). In The Birds of North America, No. 511 (A. Poole and F. Gill, eds.). The Birds of North America, Inc., Philadelphia, PA.

Cooper's Hawk takes Rock Pigeon

Click to view a substantially larger image.
Almost all of the birds we observe at our feeders are the native species one would expect in cottage country. Exceptions include three European Starlings (Sturnus vulgaris) that showed up for the first time this past month. Only once before have Martha and I seen feral Rock Pigeons (Columba livia) from our property, a high-flying flock that wheeled over our bay, heading west in high gear last September. We know of a few small flocks, several km to the north and south, that take advantage of the shelter and nesting opportunities afforded by bridges along Highway 28. Perhaps it was such an overflying trio that observed the many Common Grackles (Quiscalus quiscula), Brown-headed Cowbirds (Molothrus ater) and Red-winged Blackbirds (Agelaius phoeniceus) at our feeders on April 23rd. The pigeons landed, tasted the cracked corn and so joined the list of 30 or so other species we've observed at the feeders. Since then, the same three Rock Pigeons have visited two or three times each day.

Late this morning, I glanced out the window and saw the three Rock Pigeons feeding along side a mixed flock of 30 or so blackbirds. The birds suddenly scattered - they are often startled by the construction-related traffic at the barge landing on our neighbour's lot. I then saw a fair-sized bird make contact with one of the fleeing Rock Pigeons and the two cartwheeled to the grass, just down slope from the feeders.

I called Martha from the kitchen and over the next five minutes, we watched the Cooper's Hawk (Accipiter cooperii) subdue and pluck the hapless dove. We were able to get a few blurry pictures by "digiscoping" our Coolpix 4500 against an 8 x 40 binocular objective. Our observations ended when an approaching motorboat flushed the hawk, which flew down slope to the east with its prey in its talons.

The pictures convey the rest of the story.

Our resident Canada Geese, celebrated below in their routing of a Red Fox, were unruffled by this particular predator. Indeed the two geese approached, on webbed feet, to within five metres of the hawk and quietly observed the pigeon's demise.

The two other Rock Pigeons returned to the feeder an hour or so later.