Beaver Mines and Steeples, Feb 23—March 1

BEAVER MINES and STEEPLES RAPTOR COUNTS

SPRING 2020

www.eaglewatch.ca

PETER SHERRINGTON

Introduction 2020 will be the 29th consecutive year that a spring raptor count has been conducted at the Mount Lorette site. Last year saw the third complete (55 days) spring count at Beaver Mines which produced a disappointing total of 1216 migrants of 18 species: 6 Turkey Vultures, 2 Ospreys, 225 Bald Eagles, 35 Northern Harriers, 47 Sharp-shinned Hawks, 7 Cooper’s Hawks, 33 Northern Goshawks, 5 Broad-winged Hawks, 3 Swainson’s Hawks, 120 Red-tailed Hawks, 5 Ferruginous Hawks, 30 Rough-legged Hawks, 642 Golden Eagles, 8 American Kestrels, 16 Merlins, 6 Gyrfalcons, 6 Peregrine Falcons, and 10 Prairie Falcons. This year will be the sixth consecutive and fourth complete count at the site which is conducted from Peter Sherrington’s house in Beaver Mines.

Vance Mattson’s 2019 42-day reconnaissance count at the Steeples site on the western flanks of the Rocky Mountains near Cranbrook, BC produced 699 birds of 8 species, including a record count of 455 Golden Eagles. This year will be his tenth consecutive count at the site.

As with the fall 2019 count, this season observers at Mount Lorette will be posting their daily results directly to the RMERF website at www.eaglewatch.ca. This blog will therefore only cover the Beaver Mines and Steeples sites although I will endeavour to keep the Lorette numbers in the summary chart at the end of the blog up to date.

Information on all the RMERF sites and reports of previous years’ spring and fall counts may be found on our website www.eaglewatch.ca.

Sunday, February 23 Beaver Mines [Day 1] 1100-1700 (Peter Sherrington and Hilary Atkinson). Light snow fell to 1115 (1.5cm). The temperature at 1100 was 0C, the high at 1300 was 4.5C and it was 1C at the end of observation at 1700. Winds were light E-NE to 1115 and then SW 30-40 gusting 60 km/h for the rest of the day. Cloud cover was 80% cumulus at 1200 and 70% cumulus, cirrus and altocumulus at 1300 and was then 100% altostratus and cumulus for the rest of the day that produced flurries and brief periods of light snow. A total of 11 migrant raptors was seen between 1128 and 1546 that comprised 5a Bald Eagles, 2 light morph Rough-legged Hawks and 4a Golden Eagles. Other birds seen were 16 Rock Pigeons, 1 Eurasian Collared Dove, 2 Downy Woodpeckers, 1 Hairy Woodpecker, 1 Northern Flicker, 2 Steller’s Jays, 1 Black-billed Magpie, 29 Common Ravens, 16 Black-capped Chickadees, 20 Mountain Chickadees, 1 Red-breasted Nuthatch, 1 White-breasted Nuthatch, 5 Evening Grosbeaks, 56 Pine Grosbeaks and a flock of 35 Grey-crowned Rosy Finches that flew high to the north at 1314 which were the first to be seen in the area this year.

6 hours BAEA 5, RLHA 2, GOEA 4 TOTAL 11

Monday, February 24 Beaver Mines [Day 2] 0800-1700 (Peter Sherrington and Hilary Atkinson). The temperature at 0800 was -5C, the high at 1500 was -2.5C and it was -4C at 1700. Winds were variable NE-SSE all day, generally light but occasionally rising to 16-18 km/h and cloud cover was 100% low stratus and cumulus all day. Light snow fell to 1315 (5 cm) and moderate to light snow after 1545 that produced a further 3 cm. The ridge was periodically visible in the morning and was completely clear between 1330 and 1545 but the generally light upslope winds were not conducive to migration and no migrant raptors were seen although a non-migrant adult Bald Eagle flew to the NE at 1443. Other birds seen were 1 Downy Woodpecker, 2 Hairy Woodpeckers, 3 Steller’s Jays, 4 Blue Jays, 4 Common Ravens, 15 Black-capped Chickadees, 20 Mountain Chickadees, 1 Red-breasted Nuthatch, 1 European Starling (the first for the year), 12 Evening Grosbeaks, 62 Pine Grosbeaks and a pair of Dark-eyed Juncos of the race hyemalis that has been present in the yard since January 1.

9 hours (15) TOTAL 0 (11)

Tuesday, February 25 Beaver Mines [Day 3] 0800-1815 (Peter Sherrington and Hilary Atkinson). The temperature at 0800 was -7C, the high was 1C at 1500 and 1600 and it was -1C at 1815. Winds were WSW all day 20-30 gusting 50 km/h that produced blowing snow throughout the morning and cloud cover was 100% altostratus for much of the day with the exceptions of 0800-0930 when it was 40-50% cirrostratus and scattered cumulus, and around 1600 when it briefly cleared to 60% altocumulus and cirrus. The ridge was clear all day and produced a season-high count of 22 migrant raptors between 1244 and 1717 that comprised 17a Bald Eagles, 4 Rough-legged Hawks (3 light, 1 dark) and 1a Golden Eagle. The Bald Eagles all moved after 1532 and 8 were seen between 1710 and 1717. Two non-migratory immature Golden Eagles (1sa, 1j) were also seen. Other birds seen were 7 Rock Pigeons, 1 Eurasian Collared Dove, 1 Downy Woodpecker, 1 Hairy Woodpecker, 1 Northern Flicker, 44 Common Ravens, 10 Black-capped Chickadees, 21 Mountain Chickadees, 2 European Starlings, 54 Pine Grosbeaks, 1 hyemalis Dark-eyed Junco and 1 male Red-winged Blackbird which was the first seen here this year.

10.25 hours (25.25) BAEA 17 (22), RLHA 4 (6), GOEA 1 (5) TOTAL 22 (33)

Wednesday, February 26 Beaver Mines [Day 4] 0800-1800 (Peter Sherrington and Hilary Atkinson). The temperature at 0800 was 0C, the high between 1300 and 1600 was 3C and it was 1C at 1800. Winds were W-WSW all day, 30-40 gusting 55 km/h and cloud cover was 80-100% altostratus and cumulus to 1530 after which it cleared to 50% cumulus at 1600 and 10% cumulus after 1700. There was another fairly strong raptor movement with 21 migrants seen between 0836 and 1711 that comprised 1a Bald Eagle, 8 Rough-legged Hawks (6 light, 1 dark, 1u), and 12a Golden Eagles. The highest hourly count was 5 (1 Bald and 4 Golden Eagles) between 1000 and 1100, and 12 birds moved after 1400. Other birds seen were 15 Rock Pigeons, 2 Downy Woodpeckers, 1 Hairy Woodpecker, 1 Northern Flicker, 2 Steller’s Jays, 5 Blue Jays, 1 Black-billed Magpie, 48 Common Ravens, 14 Black-capped Chickadees, 20 Mountain Chickadees, 6 Evening Grosbeaks, 60 Pine Grosbeaks and 1 hyemalis Dark-eyed Junco.

10 hours (35.25) BAEA 1 (23), RLHA 8 (14) GOEA 12 (17) TOTAL 21 (54)

Thursday, February 27 Beaver Mines [Day 5] 0745-1815 (Peter Sherrington and Hilary Atkinson). The temperature At 0745 was 1C, the high from 1300-1500 was 5C and it was 4C at 1815, winds were WSW all day, 30-40 gusting to 70 km/h, and cloud cover was 100% altostratus and cumulus to 1200 after which it was variable 10-70% altocumulus, lenticular and cirrus. These favourable conditions produced a season-high movement of 26 raptors between 0745(2a Golden Eagles) and 1634 that comprised 1a Bald Eagle, 1a Northern Goshawk, the first of the season, 4 Rough-legged Hawks (1light, 1 dark, 2u) and a season-high 20 Golden Eagles (17a, 3j). The highest hourly count was 13 between 1500 and 1600 that included 12 Golden Eagles that moved between 1507 and 1556). Other birds seen were 4 Canada Geese that flew high to the NE at 1137, 16 Rock Pigeons, 1 Eurasian Collared Dove, 2 Downy Woodpeckers, 2 Hairy Woodpeckers, 1 Black-billed Magpie, 25 Common Ravens, 16 Black-capped Chickadees, 25 Mountain Chickadees, 2 Red-breasted Nuthatches, 14 Evening Grosbeaks, 65 Pine Grosbeaks and 160 Snow Buntings that flew low over the centre of the valley in two flocks in bright late afternoon sunshine at 1720.

10.5 hours (45.75) BAEA 1 (24), NOGO 1 (1), RLHA 4 (18), GOEA 20 (37) TOTAL 26 (80)

Friday, February 28 Beaver Mines [Day 6] 0745-1800 (Peter Sherrington and Hilary Atkinson). The temperature at 0745 was 3.5C, the high at 1400 and 1500 was 10C, which is the highest so far this season, and it was 8C at 1800. Winds were SW-WSW all day 20-30 gusting 50 km/h and cloud cover was 30-0% altocumulus, cumulus and cirrus that gave sunny conditions and excellent observing conditions all day. These conditions produced a record February RMERF count of 42 migrant raptors of 4 species between 0923 and 1719 that comprised a season-high 23 Bald Eagles (19a, 2sa, 2j), a season-high 3 Northern Goshawks (2a, 1u), 2 light morph Rough-legged Hawks and 14 adult Golden Eagles. Thirteen of the Golden Eagles moved between 0923 and 1431, and all the Bald Eagles moved after 1313. Other birds seen were 1 Downy Woodpecker, 1 Hairy Woodpecker, 2 Black-billed Magpies, 22 Common Ravens, 6 Black-capped Chickadees, 14 Mountain Chickadees, 1 Red-breasted Nuthatch, 2 American Robins which were the first of the year, 9 European Starlings,  8 Evening Grosbeaks and 41 Pine Grosbeaks.

10.25 hours (56.0) BAEA 23 (47), NOGO 3 (4), RLHA 2 (20), GOEA 14 (51) TOTAL 42 (122)

Saturday, February 29 Beaver Mines [Day 7] 0745-1800 (Peter Sherrington and Hilary Atkinson). The temperature at 0745 was 1C, the high at 1100, 1300 and 1400 was 3C and it was 0.5C at 1800. Winds were WSW-W all day, 45-55 gusting 70 km/h to 1500 and then slightly moderating to 25-30 gusting 50 km/h for the rest of the day. Cloud cover was very variable as periods of light snow periodically swept down the valley from the SW and was 0-100% cumulus, cirrostratus and altocumulus to 1550 after which it was 80-100% altostratus. Snow flurries or brief periods of light snow occurred throughout but observing conditions were generally very good, as were migratory conditions. Despite this only two migrant raptors were seen: 1 adult Golden Eagle at 1156 and 1 light morph Rough-legged Hawk at 1435. One adult Bald Eagle, one light morph Rough-legged Hawk and 2 adult Golden Eagles were considered to be non-migrants. Snow fell for most of the day on the mountains to the SW of the site and also on the Waterton Mountains to the south that probably prevented migrants from reaching the site. Other birds seen were 35 Canada Geese flying high to NNE at 1027, Mallard 12 (6 pairs) floodplain pool adjacent to the creek, 4 Rock Pigeons, 1 Eurasian Collared Dove, 2 Downy Woodpeckers, 1 Hairy Woodpecker, 1 Black-billed Magpie, 29 Common Ravens, 4 Black-capped Chickadees, 12 Mountain Chickadees, 1 Red-breasted Nuthatch, 17 European Starlings, 3 Evening Grosbeaks and 48 Pine Grosbeaks

10.25 hours (66.25) RLHA 1 (21) GOEA 1 (52) TOTAL 2 (124)

February Summary Four-day counts were conducted in late February in 2017 and 208 that yielded 24 and 28 migrants respectively but poor weather conditions prevented any February observations in 2019. This year’s count is therefore compared to the average of the 2017 and 2018 counts: 7 days (+75%), 66.25 hours (+174.6%), Bald Eagle 47 (+487.5%), Northern Goshawk 4 (not recorded in 2017 or 2018), Rough-legged Hawk 21 (+1300%) and Golden Eagle 52 (+215.2%) for a total of 124 migrant raptors (+367.9%).

The Mount Lorette and Steeples counts start tomorrow, March 1.

Sunday, March 01 Beaver Mines [Day 8] 0730-1830 (Peter Sherrington and Hilary Atkinson, assisted by Gord Petersen). There was an overnight snowfall of 5 cm that ceased around 0600 and by 0730 the ridge was completely clear. The temperature at 0730 was -5C, the high at 1300 and 1500 was 2C and it was 0C at 1830. It was calm to light ENE winds to 1000 when SW winds of 20-30 gusting 50 km/h started that persisted to 1530 after which they were 40-50 gusting 70-80 km/h that resulted in extensive blowing snow in the valley. Cloud cover was initially 90% cumulus that dwindled to 10% at 1400; it was 100% cirrostratus at 1500, 10% cirrus at 1600 but after 1630 it was 90-100% altostratus. Observing conditions were generally good and a total of 22 migrant raptors comprising 8 Bald Eagles (6a, 1sa, 1j), 2 light morph Rough-legged Hawks and 12 adult Golden Eagles were seen between 1148 and 1747. The maximum hourly counts were 6 between 1400 and 1500, and 1500 and 1600. Other birds seen were 12 Canada Geese flying to the NE at 1223, Mallard 12 (6 pairs), again on the floodplain pool adjacent to the creek before they flew low to the SW at 1415, 3 Rock Pigeons, 1 Eurasian Collared Dove, 2 Downy Woodpeckers, 1 Hairy Woodpecker, 2 Steller’s Jays, 2 Blue Jays, 28 Common Ravens, 6 Black-capped Chickadees, 20 Mountain Chickadees, 2 Evening Grosbeaks, 35 Pine Grosbeaks and 1 male hyemalis Dark-eyed Junco.

11 hours (77.25) BAEA 8 (55), RLHA 2 (23), GOEA 12 (64) TOTAL 22 (146)

Sunday, March 01 Steeples [Day 1] 1200-1700 (Vance Mattson, assisted by Virginia Rasch, Daryl Calder and Marianne Kahm). The temperature at 1200 was 4C under sunny skies with 30% cumulus cloud cover, which increased to 100% grey altostratus with a temperature of 6C by 1600. Winds were S moderate to light throughout. Four migrants, 2 adult Bald Eagles and 2 adult Golden Eagles were seen between 1502 and 1549. Resident raptors were 4 Bald Eagles (3a, 1j), the resident pair of Golden Eagles, and an adult calurus Red-tailed Hawk seen at 1630,

5 hours BAEA 2, GOEA 2 TOTAL 4