RMERF counts, October 17

Wednesday, October 17 Mount Lorette [Day 24] 0815-1915 (Caroline Lambert, assisted by Katherine Petersen). The temperature was -4C at 0815, the high was 14C at 1600 and 1700 and it was 4C at the close of observation. Ground winds were light SW all day except for mid-afternoon when they gusted 25-35 km/h before becoming light again after 1600; ridge winds were probably W initially light but becoming moderate and possibly strong during the afternoon. There was another fairly strong mainly eagle migration that saw 117 birds of 3 species move between 1134 and 1836. The count comprised 6 Bald Eagles (5a, 1sa), 1u Sharp-shinned Hawk and 106 Golden Eagles (78a, 6sa, 10j, 12u). All but 2 Golden Eagles used the eastern route originating from Mount Lorette and glided high above the ridge only during the middle of the afternoon when the winds increased; otherwise there was much soaring flight, often high above the ridge during the early and late light wind periods, with these birds probably originating from the Heart Mountain area. Only 2 Golden Eagles were seen before 1300 but movement was steady thereafter and peaked at 31 birds between 1500 and 1600. Resident birds were 1 adult Bald Eagle, 1 Sharp-shinned Hawk that hunted along the river and 1 adult Golden Eagle that cruised high above the centre of the valley searching for food. With the exception of 3 American Robins all of the other 10 species of bird seen were residents. Nine visitors came to the site today.

11 hours (249.8) BAEA 6 (69), SSHA 1 (53), GOEA 106 (1825) TOTAL 117 (2070)

Wednesday, October 17 Vicki Ridge [Day 21] 0830-1835 (Peter Sherrington, assisted by Hilary Atkinson, Gord Petersen, Raymond Toal and Trevor Lewis, observing from the Waterton 61 wellsite, and Denise Cocciolone-Amatto observing from the ridgetop). It was a warm day with a starting temperature of 7C, a high at 1400 of 17C and it was 13C at the end of observation. The wind was WNW 20 km/h to 0930 after which it was mainly W 30-40 gusting to 55 km/h for the rest of the day. It was cloudless to1600 when traces of cirrus formed that developed to 10% altostratus after 1700. There was again a strong and very varied raptor movement with 225 birds of 12 species seen between 0845 and 1829. The count was 12 Bald Eagles (7a, 2sa), 1 adult female Northern Harrier, 12 Sharp-shinned Hawks (6a, 6u), 2 adult Cooper’s Hawks, a season-high 6 Northern Goshawks(4a, 2j), 2 adult light morph Broad-winged Hawks, 2 adult Red-tailed Hawks (1 light calurus, 1 dark harlani), 1 adult dark morph Ferruginous Hawk, 45 Rough-legged Hawks (39 light, 2 dark, 4u), 141 Golden Eagles (89a, 4sa, 33j, 15u), 1 male American Kestrel and 1u columbarius Merlin that was seen by Denise from the ridgetop. Movement was steady after 1000 and peaked at 61 birds between 1400 and 1500 that included 50 Golden Eagles. Only 7 Golden Eagles were seen after 1600 but 35 of the 45 Rough-legged Hawks migrated in this period including 21 after 1800. Two Mourning Cloak butterflies were also seen on the wing.

10.08 hours (185.9) BAEA 12 (110), NOHA 1 (14), SSHA 12 (565), COHA 2 (72), NOGO 6 (40), BWHA 2 (24), RTHA 2 (154), FEHA 1 (8), RLHA 45 (186), GOEA 141 (1855), AMKE 1 (12) MERL 1 (20) TOTAL 225 (3123)

Wednesday, October 17 Steeples [Day 25] 1530-1800 (Vance Mattson). The weather was again calm, cloudless and 12C but today only 4 migrants were seen: 2 Bald Eagles (1a, 1j) and 2 adult Golden Eagles. At 1600, however, the resident pair of Golden Eagles displayed aggressively around what was considered to be a migrant Golden Eagle and made high-speed passes at the bird. The male then pursued the intruder for the full distance of the ridge to the south flank of Mount Bill Nye before displaying again. It is probable, however, that the intruder was in fact a non-migrant bird that had moved into the home range of the resident pair and had been chased out. At the Mount Lorette and South Livingstone-Piitaistakis sites where thousands of migratory eagles pass over occupied Golden Eagle nest sites the resident birds do not appear to regard the migrants as intruders and often perch for extended periods under a stream of migrant birds.

2.5 hours (110) BAEA 2 (85), GOEA 2 (131) TOTAL 4 (404)