Mount Lorette Raptor Count Autumn 2011

Monday, December 12, 2011

November 15 [Day 55] (Cliff Hansen, assisted by Kevin Barker) The temperature high was -5C at 0800 which fell to -7C at 0900, rose to -6C in mid-afternoon and was -7C at 1700. Ground winds were light SSW to noon and variable in the afternoon, mainly light but occasionally gusting to 15 km/h, while ridge winds were moderate SW-W with gusts to 69 km/h. Cloud cover was initially 100% altostratus and cumulus that reduced to 70% between 1100 and 1300, increased to 90-100% cumulus and altocumulus to 1500 after which it dwindled to 20% at 1700. The western ridges were largely obscured to 1500 after which they cleared, and the eastern ridges were mainly clear all day. The first migrant raptor was a juvenile Bald Eagle at 1115 with the first of the day's 8 Golden Eagles (6a,1sa,1u) appearing at 1219, the last three of which went south at 1639. At 1408 a resident juvenile Northern Goshawk made a low pass from a tree perch at a European Starling over the Hay Meadow, but the starling escaped and flew low to the north. Other migrants included 23 Canada Geese, 5 white-headed gulls flying south at 1600, 52 Pine Grosbeaks (including a single flock of 30 birds) and 30 Common Redpolls.

9.17 hours BAEA 1 (137), GOEA 8 (3469) TOTAL 9 (3896)


October 10: subtract 1 RLHA (=9), add 1 MERL (=1) TOTAL 371

October 24: add 5 NOGO (=5) TOTAL 137

The total Golden Eagle count is 3466 (not 3469) and the total count is adjusted to 3899 (not 3896)

FINAL MOUNT LORETTE COUNT, FALL 2011 (September 20 to November 15)

The percentage variance from the average of 12 counts between 1993 and 2010 is given in parentheses. Excluded are the count at Plateau Mountain in 1997, an incomplete count in 2002, and the anomalously low (and also shorter) comparison counts conducted between 2006 and 2009.

DAYS 55 (-0.75)

HOURS 590.77 (+4.93)


OSPREY (OSPR) 3 (+16.13)

BALD EAGLE (BAEA) 137 (-53.4)



COOPER’S HAWK (COHA) 33 (+32.89)


Unidentified Accipiter (UA) 3






Unidentified Buteo (UB) 2

GOLDEN EAGLE (GOEA) 3466 (-7.32)

Unidentified eagle (UE) 2


MERLIN (MERL) 6 (-20)

GYRFALCON (GYRF) 2 (-41.5)



Unidentified Falco (UF) 3

Unidentified raptor (UU) 2

TOTAL 3899 (-11.69)

November 14 [Day 54] (Joel Duncan) The temperature at 1100 was -3C and rose to a high at 1400 of -2.5C before falling to the day's low of -7C at 1730. Ground winds were W-SW 5-10 occasionally gusting 15 km/h all day, while ridge winds were mainly SW-WSW moderate to strong with a maximum gust of 89 km/h at 1700. Cloud cover was 100% stratocumulus to 1700 after which it quickly cleared to 10% cumulus by 1730. Short (10 minute) periods of light snow occurred at 1400 and 1530 that obscured the west ridges, but the east remained clear all day. The only migrant raptor noted was an unaged Golden Eagle at 1555, and other bird species included 1 Northern Shrike, 2 Golden-crowned Kinglets, 55 Bohemian Waxwings, 4 Dark-eyed Juncos, 53 Common Redpolls and 1 Evening Grosbeak.

6.5 hours (581.27) GOEA 1 (3461) TOTAL 1 (3887)

Sunday, November 13, 2011

November 13 [Day 53 (Bill Wilson) Once again there was only a small diurnal temperature range from -1C at 0700 to a high of 0C at 1000 and 1100 which slowly dropped to the day's low of -3C at 1645. Ground winds were WSW 0-10 gusting 20 km/h for most of the day, but gusted to 35 km/h in mid-morning, while ridge winds were moderate to strong SW-WSW gusting to 116 km/h in the morning, but only 33-60 km/h in the afternoon. Cloud cover was 80-100% cumulus and stratus for most of the day, thickening after 1500 and very light snow flurries were experienced throughout the day. The eastern ridges were 10-30% (and briefly 50%) draped by cloud after 1100 while the western ridges were 70-90% obscured after mid afternoon. The first migrant raptor was a juvenile Bald Eagle at 0845 and the last was an adult Bald Eagle at 1432 while in between 7 Golden Eagles (5a,1j,1u) were counted. Six of the day's 9 raptors occurred between 1332 and 1432. There was a fair variety of other birds in relatively low numbers including 1 adult Northern Shrike, 1 Golden-crowned Kinglet, 23 Bohemian Waxwings, 1 Red Crossbill and 1 White-winged Crossbill (which perched together), 11 Pine Grosbeaks and 35 Common Redpolls.

9.75 hours (574.77) BAEA 2 (136), GOEA 7 (3460) TOTAL 9 (3886)

The adventures of “Elaine” (Golden Eagle #78453) On November 12 Elaine was still in the same general area that she has been since November 7, east of the northern end of Canyon Ferry Lake, SE of Helena, Montana.

November 12 [Day 52] (Cliff Hansen) The ridges started clearing after 1000 when the temperature was 0C which rose to the day's high of 1C at 1100 and 1500 and was still 0.5C at the end of the day. Ground winds were S-SW, calm to 5 km/h initially before increasing to 7-15 km/h with a maximum gust of 50 km/h at 1500 after which it was 0-10 km/h gusting 25 km/h for the rest of the day. Ridge winds were moderate to strong SSW-WSW with a maximum gust of 122 km/h at 1500. At 1600 the field sheets were ripped from the clipboard by a wind gust and had to be retrieved from the Kananaskis River. Cloud cover was 100% altostratus, cumulus and altocumulus all day and light snow fell all afternoon. The ridges progressively became enveloped in cloud throughout the day with the west 90% and the east 50% obscured by the end. Not surprisingly, these conditions only yielded one migrant raptor, an unaged Golden Eagle at 1142, and non-raptor species were also scarce.

6.58 hours (565.02) GOEA 1 (3453) TOTAL 1 (3877)

Friday, November 11, 2011

November 11 [Day 51] (Peter Sherrington, assisted by Chris Hunt) The temperature was 5C at 0700 and rose to a high of 6C between 1000 and 1200, falling quickly to 0C at 1700 after a cold front passed in mid afternoon. Yesterday's strong SW-SSW winds persisted throughout the morning with ground wind gusts between 26 and 55 km/h, moderating in the afternoon with gusts to 20 km/h, while ridge winds were strong SW all day gusting between 128 and 178 km/h in the morning and 61-78 km/h in the afternoon. Cloud cover was 100% altostratus and cumulus all day giving gloomy conditions but a good observation background to the east and north. The cold front brought light snow between 1345 and 1730, and both the western and eastern ridges were substantially occluded between 1500 and 1620 after which they all quickly cleared. The only migrant raptors seen from the site were single juvenile Bald Eagles moving high above the Fisher Range at 1016 and 1209, but Chris Hunt reported a juvenile Golden Eagle flapping low towards the south over HW 40 at 1701 as he was leaving, a bird that could not be seen from the Hay Meadow site. Despite the strong winds there was a persistent movement of Common Redpolls (269) and White-winged Crossbills (28) towards the south throughout the morning, and other birds included 50 Bohemian Waxwings and 8 Pine Grosbeaks and an American Dipper that flew high to the west at 1452.

10.33 hours (558.44) BAEA 2 (134), GOEA 1 (3452) TOTAL 3 (3876)

The adventures of “Elaine” (Golden Eagle #78453) On November 10 Elaine was still in the same general area that she was on November 7.

Thursday, November 10, 2011

November 10 [Day 50] (Cliff Hansen, assisted by Kevin Barker and Chris Hunt) Temperatures were well above seasonal average with 7C at 0800 rising to a high of 8C at 1100 and 1200, and it was still 6C at 1700. Ground winds were W in the morning, 5-15 gusting 25 km/h and SW in the afternoon 5-15 gusting 50 km/h, while ridge winds were strong SW all day gusting 107-146 km/h. Cloud cover was initially 70% cumulus and cirrus becoming 100% cumulus, altostratus and cirrus at 1100 which gradually diminished to 50% cumulus at 1500 before thickening again to 90% cumulus and altostratus at the end of the day: observing conditions were generally good. The tops of the high mountains to the west were obscured all day, with the cloud lowering after 1300 causing 40% obscuring of the western ridges. The day's first Golden Eagle moved at 0948 followed by a Rough-legged Hawk at 0935, but these two birds comprised the day's busiest hour and when the last bird went south at 1605 the total was just 5 birds: 1 light morph Rough-legged Hawk, 3 adult Golden Eagles and 1 columbarius Merlin of unknown sex and age. The very high winds also proved to be inimical to passerine movement with just a few small finches noted.

9.42 hours RLHA 1 (41), GOEA 3 (3451), MERL 1 (5) TOTAL 5 (3873)

The adventures of “Elaine” (Golden Eagle #78453) On November 9 Elaine was still in the same area that she was on November 7.

Wednesday, November 9, 2011

November 9 [Day 49] (Cliff Hansen). The temperature was -11C at 0800 but rose to a high of 4C between 1300 and 1600 and was still 2.5C at 1700. Ground winds were calm to light SW to 1000 after which they were SW 5-10 km/h with a maximum gust of 35 km/h at 1700, while ridge winds were moderate SW to 1300 after which they became strong with a maximum gust of 155 km/h at 1600. Cloud cover was 10% cumulus, altostratus and lenticular to 1300 after which it increased to 20-30% cumulus and lenticular until 1600 when it again increased to 60% with an altostratus arch forming east of the Fisher Range. The western ridges were 10% obscured at 1400 and by 1700 they were 40% obscured, but observing conditions in the afternoon were generally good as all birds moved high above the Fisher Range to the east. There was a reasonably strong raptor movement for November with 24 birds migrating between 1214 and 1613, which is the the second highest count for the month so far. The flight comprised 4 Bald Eagles (2a,1j,1u), 1 light morph Rough-legged Hawk, 18 Golden Eagles (14a,1sa,1j,2u) and 1 Prairie Falcon. Finches continued to move including 100 Common Redpolls, 1 Pine Siskin and 100+ undifferentiated small finches.

9.5 hours (538.69) BAEA 4 (132), RLHA 1 (40), GOEA 18 (3448), PRFA 1 (2) TOTAL 24 (3868)