RMERF counts March 2-4
Friday, March 2 Mount Lorette [Day 2] 0800-1215 (Jim Davis, assisted by Blake Weis). The temperature at 0800 was -13C, reached a high of -8C at 1000 and was -10C when the count was abandoned at 1215. Ground winds were E 30-40 km/h, cloud cover was 100% low stratus, snow fell all day and all peaks and ridges were obscured. A light morph Rough-legged Hawk flying low to the north above HW 40 near the site at 0805 was the only raptor seen.
4.25 hours (11.75) RLHA 1 (1) TOTAL 1 (1)
Friday, March 2 Beaver Mines [Day 6] 0800-1800 (Peter Sherrington). Steady light snow fell all day that obscured the ridge with the exception of 1145-1315 when the snow became very light and the ridge cleared. During this period the temperature was -8C and the wind SSE-E 10-15 km/h. At 1248 a non-migrant adult Bald Eagle soared above the Big Hill and glided to the ESE, and no other raptors were seen.
1.5 hours (45.5) TOTAL 0 (32)
Friday, March 2 Steeples (Vance Mattson) NO OBSERVATION (Weather). Intermittent snow fell to 1430 after which it became steady. Both the mountains and the valley were obscured all day.
Saturday, March 3 Mount Lorette NO OBSERVATION (Weather). Steady snow all day, all mountains obscured.
Saturday, March 3 Beaver Mines [Day 7] 0800-1700 (Peter Sherrington to 1200, Denise Cocciolone-Amatto and Raymond Toal after 1200). The temperature at 0800 was -10C, the high at 1100, 1300 and 1400 was -7C and it was -10C at 1700. Winds were SSW 0-5 km/h to 0900 and E-SE for the rest of the day 11-22 km/h and cloud cover was 100-80% stratus all day and light to very light snow fell for most of the day. The ridge occasionally cleared but no migrants were seen and 2 resident Golden Eagles (1j, 1u) were the only raptors seen.
9 hours (54.5) TOTAL 0 (32)
Saturday, March 3 Steeples [Day 1] 1300-1800 (Vance Mattson). The recent snow made access to the usual Bill Nye site difficult so Vance observed from about 1 km north of the site. It was a mainly sunny day, a temperature of 3C with moderate to strong S-SW winds and an initial cloud cover of 80% altostratus and cumulus that decreased to 50% by 1500. The higher peaks were partially obscured for most of the day although the main migration route remained clear. The season’s first migrant was a Bald Eagle that glided low in front of the site at 1325, but the next birds, 1 Bald Eagle and 3 Golden Eagles, were not seen until 1605-1612 and the last birds, 2 Bald Eagles and 4 Golden Eagles, occurred between 1710 and 1731. The final count of 11 birds was 4 adult Bald Eagles and 7 adult Golden Eagles. A non-migrant juvenile Golden Eagle hunted the ridge in high winds between 1525 and 1535 before perching. A Pileated Woodpecker flew over the site at 1552.
5 hours (5) BAEA 4 (4), GOEA 7 (7) TOTAL 11 (11)
Sunday, March 4 Mount Lorette [Day 3] 0655-1805 (Bill Wilson, assisted by Cliff Hansen). The starting temperature was -16C, the high was -9C at 1500 and 1600 and it was -10C at 1800. Ground w1nds were WNW 0-3 km/h to 1100, then mostly NE-E to the end of the day. While ridge winds appeared to be moderate SW all day that combed snow off the ridges. Cloud cover was 90-100% altostratus to 1200, the variable 20-70% cirrus, cumulus and stratus for the rest of the day that generally gave sunny periods or hazy sunshine. Very light snow fell to 1000 and again after 1700. The east ridges were essentially clear all day, while the west was 20-30% obscured to 1200 and 10-30% obscured in the afternoon. A total of 5 migrants, 2 adult Bald Eagles and 3 adult Golden Eagles, were seen between 1035 and 1700, with 2 of the Golden Eagles moving between 1500 and 1600. All birds migrated on the eastern route, the Golden Eagles moving to Mount Lorette and then to the NW, while the Bald Eagles moved to the north from the northern end of the Fisher Range. Other birds seen were 1 high-flying woodpecker sp., 2 Grey Jays, 3 Common Ravens, 2 American Dippers and 1 Pine Grosbeak. Fourteen visitors came to the site throughout the day.
11.16 hours (22.91) BAEA 2 (2), GOEA 3 (3) TOTAL 5 (6)
Sunday, March 4 Beaver Mines [Day 7] 0800-1815 (Peter Sherrington). The temperature was -15C at 0800, reached a high of -8C at 1200 and 1300 and was -10C at the end of observation. Winds were light variable NW-SW to 1200 and ESE 11-13 km/h throughout the afternoon, although a moderate WSW upper flow developed after 1300 it never lowered to ridge level. Cloud cover was 100-70% generally thin stratocumulus and cirrostratus with minor cumulus that gave hazy sunshine all day. Very light snow fell to 0900 but the ridge was clear all day. Despite the excellent observing conditions, the light winds were not conducive to raptor movement and the only migrants recorded were adult Bald Eagles at 1455 and 1655, and a light morph Rough-legged Hawk at 1659. Two resident Golden Eagles (1a and 1j) were also present. At 1837, 3 Canada Geese flew high to the NW which were the first migrants of the species for the season.
10.25 hours (64.8) BAEA 2 (18), RLHA 1 (4) TOTAL 3 (35)
Sunday, March 4 Steeples [Day 2] 1200-1700 (Vance Mattson). Observation was again from about 1 km north of the Bill Nye site. It was a mostly sunny day with the temperature rising to 1C from a low of -1C and it was calm throughout. Cloud cover was 40% altocumulus tom 60% cumulus and altostratus and the ridges were clear. A total of 3 adult Golden Eagles moved between 1220 and 1355, and resident adult and 1 juvenile Golden Eagles hunted the ridges and valleys throughout much of the observation period.
5 hours (1), GOEA 3 (10) TOTAL 3 (14)
SUMMARY COUNTS, SPRING 2018 | |||
MOUNT LORETTE March 1- | BEAVER MINES February 25- | STEEPLES March 1- | |
DAYS | 3 | 8 | 2 |
HOURS | 22.91 | 64.8 | 10 |
TURKEY VULTURE (TUVU) | 0 | 0 | 0 |
OSPREY (OSPR) | 0 | 0 | 0 |
BALD EAGLE (BAEA) | 2 | 18 | 4 |
NORTHERN HARRIER (NOHA) | 0 | 0 | 0 |
SHARP-SHINNED HAWK (SSHA) | 0 | 0 | 0 |
COOPER’S HAWK (COHA) | 0 | 0 | 0 |
NORTHERN GOSHAWK (NOGO) | 0 | 0 | 0 |
Accipiter sp. (UA) | 0 | 0 | 0 |
BROAD-WINGED HAWK (BWHA) | 0 | 0 | 0 |
SWAINSON’S HAWK (SWHA) | 0 | 0 | 0 |
RED-TAILED HAWK (RTHA) | 0 | 0 | 0 |
FERRUGINOUS HAWK (FEHA) | 0 | 0 | 0 |
ROUGH-LEGGED HAWK (RLHA) | 1 | 4 | 0 |
Buteo sp. (UB) | 0 | 0 | 0 |
GOLDEN EAGLE (GOEA) | 3 | 13 | 10 |
Eagle sp. (UE) | 0 | 0 | 0 |
AMERICAN KESTREL (AMKE) | 0 | 0 | 0 |
MERLIN (MERL) | 0 | 0 | 0 |
GYRFALCON (GYRF) | 0 | 0 | 0 |
PEREGRINE FALCON (PEFA) | 0 | 0 | 0 |
PRAIRIE FALCON (PRFA) | 0 | 0 | 0 |
Falco sp. (UF) | 0 | 0 | 0 |
Unidentified Raptor (UU) | 0 | 0 | 0 |
TOTALS | 6 | 35 | 14 |
RMERF spring 2018 counts: Mount Lorette and Steeples March 1, Beaver Mines February 25-March 1
MOUNT LORETTE, BEAVER MINES and STEEPLES RAPTOR COUNTS
SPRING 2018
PETER SHERRINGTON
Introduction 2018 is the 27th consecutive year that a spring raptor count has been conducted at the Mount Lorette site. In 1992 an eight-day reconnaissance count starting on March 20 at the site established that Golden Eagles moved to the northwest 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 seventy 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 and subsequent years the count period was extended by 1 week (March 1 to April 22) and we will use the same period this spring.
Last year’s (2017) spring count saw a combined species passage of 2672 birds that included a Golden Eagle count of 2256. The March combined species count of 2014 represented 89.3% of the total count, while April’s count of 290 was 47.4% below average, but the April total of 242 was 45.2% below average. The maximum Golden Eagle count was 363 on March 19 and 4 other days had counts exceeding 100 birds. Eleven species occurred in higher than average numbers: Bald Eagle (216), Northern Harrier (5), Cooper’s Hawk (9), Northern Goshawk (27), Broad-winged Hawk (3), Swainson’s Hawk (2), Red-tailed Hawk (70), Rough-legged Hawk (23), American Kestrel (4), Merlin (11), Gyrfalcon (3) and Peregrine Falcon (4). Only 3 species were below average: Sharp-shinned Hawk (16), Golden Eagle (2256) and Prairie Falcon (1). The combined species median passage date was March 20, 2 days earlier than average.
Last year saw the second complete (56 days) count at Beaver Mines which produced 1992 migrants of 18 species: 2 Turkey Vultures, 10 Ospreys, 304 Bald Eagles, 70 Northern Harriers, 71 Sharp-shinned Hawks, 14 Cooper’s Hawks, 72 Northern Goshawks, 15 Broad-winged Hawks, 3 Swainson’s Hawks, 214 Red-tailed Hawks, 7 Ferruginous Hawks, 68 Rough-legged Hawks, 1069 Golden Eagles, 6 American Kestrels, 18 Merlins, 5 Gyrfalcons, 11 Peregrine Falcons, and 9 Prairie Falcons. This year will be the fourth consecutive count at the site which is conducted from my house in Beaver Mines.
Vance Mattson’s 2017 15-day reconnaissance count at the Steeples site on the western flanks of the Rocky Mountains near Cranbrook, BC produced 515 birds of 8 species that included a record single day high count of 147 raptors (12 Bald Eagles, 133 Golden Eagles) on March 17. This year will be the eighth consecutive count at the site.
Rosemary and Cliff Hansen are organizing the Mount Lorette count and welcome visitors to the site. If you are interested in volunteering as a “Sky-sweeper” (no previous experience needed: just good eyes and binoculars) or as an Observer please contact Rosemary at rosemary.rmerf@gmail.com. Details of how to find the site and other useful information can be found on our website, www.eaglewatch.ca. Generally the best time to see migrating eagles is in the afternoon, and the chart below gives an indication of the dates when other raptors are expected to be moving at the site.
SUMMARY OF RAPTOR SPECIES SPRING OCCURRENCES, MOUNT LORETTE (March 1-April 22. 1993-2017) | |||
species | average first occurrence | earliest first occurrence | average species median passage date |
TUVU | 3 records of 4 birds:18 and 31 March, 10 April | 18 March | n/a |
OSPR | 17 April | 9 April | n/a |
BAEA | 3 March | 1 March | 28 March |
NOHA | 2 April | 3 March | 13 April |
SSHA | 23 March | 2 March | 12 April |
COHA | 1 April | 16 March | 13 April |
NOGO | 11 March | 1 March | 30 March |
BWHA | 4 records of 6 birds: 1, 13, 19 and 24 April | 1 April | n/a |
SWHA | 2 birds on 15 April 2017 | 15 April | n/a |
RTHA | 22 March | 9 March | 9 April |
FEHA | 3 records of 4 birds: 6, 9 and 15 April | 6 April | n/a |
RLHA | 21 March | 7 March | 8 April |
GOEA | 2 March | 1 March | 22 March |
AMKE | 16 April | 4 April | n/a |
MERL | 20 March | 6 March | 4 April |
GYRF | 25 March | 12 March | n/a |
PEFA | 6 April | 15 March | n/a |
PRFA | 28 March | 7 March | n/a |
Sunday, February 25 Beaver Mines [Day 1] 1400-1800 (Peter Sherrington). Winter did not seriously arrive in the area until around 20 December, but when it did it has been characterized by generally below-average temperatures, persistent periods of heavy snowfall and downslope winds that have regularly gusted between 80 and 110 km/h. Daily road surveys conducted in the study-area yielded only 9 Golden Eagles during the whole of January but 26 were seen between February 7 and 25 indicating some early northward movement through the prairies. Short periods of observation from my house on February 12 and 20 produced 2 adult and 4 adult migrant Bald Eagles respectively, and the cumulative count for the road surveys for the year to date is an above average 257 birds. By contrast, wintering Rough-legged Hawks have been relatively scarce (36 in January, 31 in February), especially considering that we counted over 500 southbound migrants on the fall Vicki Ridge count. This probably reflects the persistent thick snow cover that makes the hunting of small mammals difficult. Other raptors have also been scarce with yearly totals to date of 1u Sharp-shinned Hawk (January 13), 1 adult Cooper’s Hawk seen on four occasions between January 28 and February 16, 5 Northern Goshawks, 1 adult light morph calurus Red-tailed Hawk seen in Beaver Mines on January 11 and 16, 1u Richardson’s Merlin, 2 adult male grey morph Gyrfalcons and seven sightings of single Prairie Falcons.
Today the temperature was -3C that fell to -5C at 1800, winds were W-WSW 20-35 km/h during the count period, but had been gusting to 80 km/h during the morning, cloud cover was 100% stratus all day and steady snow fell to 1400 when it became light, the ridge was visible and observation could begin. The snow finally ceased at 1645 after which an adult Bald Eagle was seen at 1707 and a dark morph Rough-legged Hawk at 1734: the first migrants of the official 2018 count.
4 hours (4) BAEA 1 (1), RLHA 1 (1) TOTAL 2 (2)
Monday, February 26 Beaver Mines [Day 2] 0800-1800 (Peter Sherrington). The temperature at 0800 was -8C, reached a high of -1C from 1100-1300 and was -4C at the end of observation. Winds in the morning were NW-W 10-15 km/h but were WSW in the afternoon 30-40 gusting 50 km/h causing blowing snow in the valley. Much of the day was cloudless, with a maximum of 20% scattered cumulus occasionally developing, which produced a very welcome sunny day. Despite the ideal migration conditions the first migrant and first Golden Eagle of the season (surprisingly a juvenile bird) did not move north until 1225 and thereafter migration was slow but steady with at least one eagle occurring each hour until the close: the last bird was an adult Bald Eagle at 1702. The final count of 7 birds was 3 adult Bald Eagles and 4 Golden Eagles (3a, 1j), not a bad day for late February.
10 hours (14) BAEA 3 (4), GOEA 4 (4) TOTAL 7 (9)
Tuesday, February 27 Beaver Mines [Day 3] 0800-1800 (Peter Sherrington). The temperature was -7C at 0800, the high was -2C from 1300-1500 and it was -5C at the end of observation. Winds were W-WSW all day 30-45 gusting 60 but reaching 70-80 km/h in the early afternoon and horizontal light snow originating near the continental divide to the SW persisted between 1100 and 1515, even when the sky was essentially cloudless. Cloud cover was 60-100% altostratus, altocumulus and cumulus for most of the day, but the edge of the downslope cloud cover occasionally retreated to the SW leaving clear skies. Observation conditions were good throughout but the first migrant, an adult Bald Eagle, was not seen until 1310 and only 5 more birds moved, 4 of which occurred between 1554 and 1636. The final count was 2 adult Bald Eagles, 1 light morph Rough-legged Hawk and 3 Golden Eagles (2sa, 1j). Non-migrant birds were 1 adult Northern Goshawk and 2 Golden Eagles (1a, 1j).
10 hours (24) BAEA 2 (6), RLHA 1 (2), GOEA 3 (7) TOTAL 6 (15)
Wednesday, February 28 Beaver Mines [Day 4] 0800-1800 (Peter Sherrington). At 0800 the temperature was -6C, the high was 0C at 1400 and it was -3C at 1800. Winds were again W-WSW all day, 10-30 km/h to 1030, 35-45 gusting 55 km/h to 1600 and 30-35 km/h for the final 2 hours. Cloud cover was 90-60% altostratus and cumulus in the morning that produced occasional snow flurries, and 20-30% cumulus throughout the afternoon that gave excellent observing conditions. A season-high total of 14 raptors moved slowly but steadily between 0946 and 1717 with the last 4 birds occurring between 1701 and 1717. The final count was 7 adult Bald Eagles, 1 light morph Rough-legged Hawk and 6 Golden Eagles (5a, 1j). One or two adult resident Golden Eagles were also present.
10 hours (34) BAEA 7 (13), RLHA 1 (3), GOEA 6 (13) TOTAL 14 (29)
Thursday, March 1 Mount Lorette [Day 1] 0830-1530 (Blake Weis, assisted by Cliff Hansen). The starting temperature was -7C, the high was -1C at 1100 and fell to -2C at 1530 when the count was abandoned for the day as steady snow fell. Ground winds were calm to light SE-SW in the morning and N-NNE 5-12 gusting 20 km/h in the afternoon, and ridge winds probably followed the same pattern. Cloud cover was 100% altostratus to 1000, 70-100% altostratus, cumulus and altocumulus to 1400 that allowed brief sunny breaks and 100% stratus and cumulus for the rest of the day that brought light to moderate snow that became steady after 1500.The east ridges were 70% obscured at the start but completely cleared between 1000 and 1100 before clouding over again to 90% by 1500. The west was initially 10% obscured which gradually increased and reached 90% at the end of observation. No migrant raptors were seen, but a resident Northern Goshawk called near the site at 0930 and 2 resident adult Bald Eagles perched by the river before flying low to the west. The only other birds seen were 1 Grey Jay, 6 Common Ravens and 2 American Dippers. Five visitors came to the site in the morning when the weather was quite pleasant.
7.5 hours (7.5) TOTAL 0 (0)
Thursday, March 1 Beaver Mines [Day 5] 0800-1800 (Peter Sherrington). The temperature at 0800 was -7C, the high again was 0C at 1100 and 1200 and winds were light (<10 km/h) W-NW in the morning, and ESE-E 15-20 km/h in the afternoon. Cloud cover was 80-100% altostratus and altocumulus in the morning that allowed hazy sunshine, and 100% stratus in the afternoon with light snow starting at 1540 that persisted for the rest of the afternoon although the ridge remained clear during the observation period. The only migrants seen were 3 adult Bald Eagles at 1137 that soared for several minutes above the ridge without gaining altitude in the light winds, before gliding low to the NW over the valley. A resident juvenile Golden Eagle soared briefly above the ridge at 1358, but no further migrants were seen.
10 hours (44) BAEA 3 (16) TOTAL 3 (32)
Thursday, March 1 Steeples [Day 1] (Vance Mattson) NO OBSERVATION (Weather). The mountains were obscured all day and snow is forecast for tomorrow.
SUMMARY COUNTS, SPRING 2018 | |||
MOUNT LORETTE March 1- | BEAVER MINES February 25- | STEEPLES March 1- | |
DAYS | 1 | 5 | 0 |
HOURS | 7.5 | 44 | 0 |
TURKEY VULTURE (TUVU) | 0 | 0 | 0 |
OSPREY (OSPR) | 0 | 0 | 0 |
BALD EAGLE (BAEA) | 0 | 16 | 0 |
NORTHERN HARRIER (NOHA) | 0 | 0 | 0 |
SHARP-SHINNED HAWK (SSHA) | 0 | 0 | 0 |
COOPER’S HAWK (COHA) | 0 | 0 | 0 |
NORTHERN GOSHAWK (NOGO) | 0 | 0 | 0 |
Accipiter sp. (UA) | 0 | 0 | 0 |
BROAD-WINGED HAWK (BWHA) | 0 | 0 | 0 |
SWAINSON’S HAWK (SWHA) | 0 | 0 | 0 |
RED-TAILED HAWK (RTHA) | 0 | 0 | 0 |
FERRUGINOUS HAWK (FEHA) | 0 | 0 | 0 |
ROUGH-LEGGED HAWK (RLHA) | 0 | 3 | 0 |
Buteo sp. (UB) | 0 | 0 | 0 |
GOLDEN EAGLE (GOEA) | 0 | 13 | 0 |
Eagle sp. (UE) | 0 | 0 | 0 |
AMERICAN KESTREL (AMKE) | 0 | 0 | 0 |
MERLIN (MERL) | 0 | 0 | 0 |
GYRFALCON (GYRF) | 0 | 0 | 0 |
PEREGRINE FALCON (PEFA) | 0 | 0 | 0 |
PRAIRIE FALCON (PRFA) | 0 | 0 | 0 |
Falco sp. (UF) | 0 | 0 | 0 |
Unidentified Raptor (UU) | 0 | 0 | 0 |
TOTALS | 0 | 32 | 0 |