I stopped for lunch just past Cultus Lake as the weather was clearing after the rain, hail and wind. I had a good view of the sky and in short order a Rough-legged Hawk flew over. In over just over 30 minutes I tallied four Rough-legged Hawks, six Red-tailed Hawks, 14 Northern Harriers, seven Bald Eagles, an Osprey, three Turkey Vultures, and singles of Merlin, Sharp-shinned Hawk and Cooper's Hawk. It was quite the show and I wonder if it was more due to the fact the weather had just improved and possibly other factors such as wind etc made the site desirable as I was not at a very high elevation. For part of it almost half of the sky I could see was covered by low cloud and possibly some others had passed over that. Every bird was flying to and from the same direction which was NE which followed Columbia Valley which is between Vedder Mountain and International Ridge. Maybe it acts as a bit of a funnel? Worth future checks methinks!
Here's a shot of one of the Rough-legs that passed over the lowest.
imperialbirders Mike in areas where migrating raptors congregate there can be 'kettles' of hundreds of birds as a time circling overhead. Here, I've only seen maybe 6-8 birds at any time overhead at areas like Sumas Mountain and maybe getting 15-20 birds passing per hour. I think what I witnessed was more due to the recent poor weather that stalled their movements and then when things improved they all started to move on again at the same time thus the higher than usual numbers.
Gord Fraser Valley Birding Administrator eBird Regional Editor (Fraser Valley)