The typical migration through, and residence and breeding of these birds at Presqu'ile provincial park, roughly 40 km to the south, occurs from late March to mid-October, with extreme sightings on 10 March and 14 November (LaForest, 1993, pp.247-248). The tree swallow is a common summer resident and breeding species at Presqu'ile. In Peterborough county, to the northwest, the tree swallow has been noted from 03-04 March to 02 October, and exceptionally to 21 October (Sadler, 1983, pp.110,176). It is the most abundant swallow in the county, collecting in great flocks with other swallows prior to departure. "Because of its early arrival, it is often caught in a severe cold spell, when it will feed on berries" (ibid., p.110). This was the case with five birds seen on 30-31 March 2007, prior to some cold late-winter weather. Bent (1942) describes the early appearance of the tree swallow, and the adaptation of the species to harsh weather on migration (ibid., pp.384-400).
BENT,AC (1942) Life Histories of North American Flycatchers, Larks, Swallows, and their Allies. Dover Publications, Inc., reprint of Smithsonian Institution Bull. 179 in 1963, 555pp.
LaFOREST,SM (1993) Birds of Presqu'ile Provincial Park. Friends of Presqu'ile Park / Ontario Ministry of Natural Resources, 436pp.
SADLER,D (1983) Our Heritage of Birds: Peterborough County in the Kawarthas. Peterborough Field Naturalists / Orchid Press, Peterborough, ON, 192pp.