The South Livingstone Raptor Count for the spring migration of 2009 has now begun. First official day of counting began on 15th February 2009. Follow the daily movement of raptors on this blog updated daily by Peter Sherrington.

Sunday, May 17, 2009

May 17 [Day 80] (Piitaistakis Ridge) It was another warm day with the temperature already 8.5C at 0800 and reaching 16C after 1600, but the heat resulted from strong WNW-W winds all day that peaked at 105 km/h at 1300 and only slightly moderated to 50-70 km/h in the afternoon. Cloud cover was 70-100% altostratus, cirrus and lenticular cloud all day producing hazy sunshine and good observing conditions. Normally, strong winds favour movement of the larger raptors but today 10 of the 15 migrants were juvenile Sharp-shinned Hawks, which is the second highest daily count this season, and there was also an unidentified accipiter. The other migrants were an Osprey (bringing the season’s total to 21, the same as last spring’s count), an adult light morph Broad-winged Hawk, a juvenile Golden Eagle and a female American Kestrel. As yesterday, the only migrant passerine species was Grey-crowned Rosy-Finch with 165 moving north along the ridge. The highlight of the day (and probably of the season), however, was a small Chaetura swift that flew low to the north along the western edge of the ridge at 1325 just 25 m away in perfect light. The bird was a uniform dark brown colour showing absolutely no contrast between the throat and the rest of its body, its wings were significantly longer than those of a Vaux’s Swift and its wing-beat somewhat slower than that species: in fact it was reminiscent of a small, dark brown version of a Black Swift. The bird was almost certainly a Chimney Swift which, I believe, is not on the provincial list and was listed in 2007 by COSEWIC as a threatened species. It is interesting that the bird arrives back in its Manitoba breeding grounds in mid-May which is consistent with its occurrence as a vagrant here today. A small, dark swift flying high to the SE of the site at 1840 was probably the same bird. Also remarkable was the first spring occurrence of a Thirteen-lined Ground Squirrel which we first recorded at the site last fall, strongly suggesting that this prairie species successfully hibernated at an altitude of 1900 m! 12.75 hours (909) OSPR 1 (1), SSHA 10 (95), UA 1 (4), BWHA 1 (3), GOEA 1 (2715), AMKE 1 (7) TOTAL 15 (3727)

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