April 5 [Day 41] (Valley View site) Finally a spring-like day! The temperature rose to 11C from a low of -8C, ground winds were variable to SW/WSW light in the morning but gusting to 30 km/h in the afternoon and ridge winds were generally W light in the morning but strengthening in mid afternoon before moderating again in the evening. The sky was cloudless until 0900 when thin cirrus began to develop that gradually spread to 90% at 1900 and thickened by late afternoon providing excellent observing conditions. Early morning movement was slow with only 2 Golden Eagles passing before 1100. The pace subsequently quickened although there were a number of periods without birds, but it was only after 1800 that there was concerted movement with 30 of the day’s 81 migrants occurring, the last going north at 1957. The counts of 8 Red-tailed Hawks (all calurus) and 3 Merlins (all columbarius) were the highest yet this season, and the 30 Bald Eagles is the second highest count after the 35 on March 21. For the first time immature Golden Eagles (17, 51.5%: 10 subadults and 7 juveniles) outnumbered adults (16), and other highlights included a stunningly white adult Ferruginous Hawk and a very pale grey morph adult Gyrfalcon. The 9 species of migrant raptors equals the season high, and a non-migrant Prairie Falcon was also seen. The resident pair of Red-tailed Hawks comprises a light and rufous morph as last year (the same birds?) and attempted copulation was seen at 1630. The resident pair of Golden Eagles was conspicuous all day, on occasion displaying together, and in the afternoon they were joined by a non-migrant juvenile bird which at 1642 engaged in a prolonged high-intensity display with one of the adult birds. The first Tree Swallow of the year appeared at 1127, 3 day’s later than last year’s first occurrence. 13.33 hours (441.3) BAEA 30 (312), SSHA 1 (8), NOGO 2 (54), RTHA 8 (27), FEHA 1 (3), RLHA 2 (19), GOEA 33 (2344), MERL 3 (8), GYRF 1 (2) TOTAL 81 (2792)
Mount Lorette (Bill Wilson) The temperature ranged from -10C to 10C , ridge winds were W to SW moderate, diminishing in the afternoon, and cloud cover was 70-100% cirrus and cirrostratus for most of the day except for 1300-1500 when it fell to 10-20%, but generally observing conditions were good. The first migrant, a Golden Eagle, was seen at 1049 but by 1300 only 1 more bird had moved. The rate then gradually increased with maximum passage of 10 birds from 1900 to 2000, with the last Golden Eagle moving at 1955. The count of 16 Bald Eagles was by far the highest this season, and 50% of the 32 Golden Eagles seen were immature (7 subadults and 9 juveniles), gratifyingly similar to the P-SL totals. 13.83 hours (360.2) BAEA 16 (63), NOGO 1 (6), RLHA 1 (3), GOEA 32 (789) TOTAL 50 (877)