Wednesday, March 7, 2012


Introduction 2011 is the 21th consecutive year that a spring raptor count has been conducted at the Mount Lorette site. In 1992 an 8-day reconnaissance count established that Golden Eagles moved to the north in significant numbers through the Rocky Mountain Front Ranges. Most of the birds moved along the Fisher Range, crossing the Kananaskis Valley to Mount Lorette before continuing their migration to the northwest. A 48 day (393 hour) count at the site in the spring of 1993 yielded 4140 migrating Golden Eagles and the following year a 70 day (649 hour) count produced 4213 birds which remains the highest spring count ever for the species at Mount Lorette. Between 1994 and 2007 extensive spring counts averaging 82 days (897 hours) were conducted at the site with a maximum count in 2005 of 94 days (1238 hours). Despite the steady increase in observer effort during this period, the number of migrating Golden Eagles counted has steadily and significantly decreased since 1995. In 2006 RMERF conducted it first complete fall count at the Piitaistakis-South Livingstone site near the Crowsnest Pass in SW Alberta and in 2008-10 also conducted full spring counts there. During this period extensive comparative counts were made at Mount Lorette between March 1 and April 15 which is coincident with the height of the Golden Eagle migration and during which period over 90% of the population moves north. Observer effort from 2008-10 at Mount Lorette averaged 43 days (487 hours) with a maximum count of 46 days (519 hours) in 2010 when no days were lost to inclement weather. In 2011 the count period was extended by 1 week (March 1 to April 22) and we plan to observe during the same period this spring.
Cliff Hansen is again coordinating the Lorette count this spring and would welcome volunteers to assist the Principal Observers at the site. If you are interested in helping you can contact him at 403-673-2422 or 403-609-0691 (cell), or just turn up at the site with your binoculars and warm clothing!

March 1 [Day 1] (Cliff Hansen, assisted by Kevin Barker and Chris Hunt). There was only 1-2 cm of patchy snow in the Hay Meadow at the start of the count despite above average snowfall on the mountains to the west. The temperature at 0900 was -15C that rose to -3C at 1500 and was -6C at 1700. Ground winds were initially E 0-3 km/h, then NE, ENE and finally N 5-15 km/h, while ridge winds appeared to be moderate W. It was initially cloudless but by 1000 cloud cover was 60% cumulus, altostratus and cirrus and after1200 it was 100% stratus and altocumulus until the end of the day. Snow started at 1700 after which all ridges were obscured. The only migrant raptor was an early subadult Golden Eagle at 1334, although single adult non-migrant Bald Eagle and Northern Goshawk were also recorded. A flock of about 30 White-winged Crossbills was seen near the parking area. 10.33 hours (10.33) GOEA 1 (1) TOTAL 1 (1)

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