The ruby-crowned kinglet is a delightful, very small songbird, with wing bars, a white eye ring, and (in the male) a seldom-seen red crown patch. It tends to spend summers to the north, and winters to the south, thus it is expected to show peak appearances in spring and fall. The observations are insufficient for a definitive result. Earliest and latest observations are 19 April and 16 October, generally with 1-2 observations in each month through the summer, except for a lack of June sightings.
The golden-crowned kinglet is similar, except with the eye ring replaced by a dark eye stripe, and an orange to yellow crown patch in both sexes. It has been seen in a narrow time window, 15 September to 26 October. Both species of kinglet are easily overlooked: in a fleeting appearance it may not be possible to distinguish the two species. This leads to a unique result, with 24 definitive sightings in 23 years, plus a further 18 sightings of "kinglet, sp.".
At Presqu'ile provincial park, roughly 40 km to the south, the ruby-crowned kinglet is a common migrant from mid-April to late May, and mid-September to early November (LaForest, 1993, pp.272-273). Reported numbers have been very large, up to several hundred a day in April. There have been two summer and two winter records, but the principal status of migrant is clear. A generally similar story applies to the golden-crowned kinglet (ibid., pp.271-272). This kinglet is a year-round resident and breeds in the park, though again it is an abundant spring migrant, with Doug McRae reporting maximum estimates of 2,000 to 3,000 individuals in a day, on 15 April 1985. The autumn migration is also quite pronounced, with peak numbers in the latter half of October.
Similar patterns apply also in Peterborough county, to the northwest (Sadler, 1983, p.120), with migrant periods generally around 04 March to 01 May and 03 September to 01 November (golden-crowned) and 03 April-03 May and 04 August-04 November (ruby-crowned).
Overall patterns may be recorded by the breeding bird atlases (Cadman et al., 1987, pp.314-317; 2007, pp.422-425). Observations reveal a paucity of breeding in southwest and southeast Ontario, with most birds spending their summers between Georgian Bay and the Ottawa valley, and all across the province to the far north. The greatest density for each species is in northwest Ontario, west and north from Lake Nipigon toward the Manitoba border.
Cadman,MD, Eagles,PFJ and Helleiner,FM (1987) Atlas of the Breeding Birds of Ontario. Federation of Ontario Naturalists and Long Point Bird Observatory, published by University of Waterloo Press, 617pp.
Cadman,MD, Sutherland,DA, Beck,GG, Lepage,D and Couturier,AR (editors) (2007) Atlas of the Breeding Birds of Ontario, 2001-2005. Bird Studies Canada, Environment Canada, Ontario Field Ornithologists, Ontario Ministry of Natural Resources, and Ontario Nature, 706pp.
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.