Ken and Jan in Dauphin had 48 swifts roosting and noted many entries after "the magic hour". This was an increase from the 11 swifts seen on the first national monitoring night.
In St. Adolphe, the upward trend in numbers continued but mystery shrouded our evening. Rob had 1 +2 in at the SE + NE Club Amical chimneys respectively; I had 2 in at Main St.; Jacquie had 0 swifts at Brodeur Bros.; and Frank counted 2 in at the Church. Then "something" happened at the very end of the roosting hour. The Church swifts left after a mob of 8 chsw came screaming by.
About half way through the monitoring period, I saw a flock of what looked like 9 swifts over the Red River. Rob, who was a long block away, saw 8 swifts just at the end of the observation period, as they moved north past Brodeur Bros. and then to the Church. Rob came back to the Church wondering who got all the roosting birds. Nobody did. We had 10 airborne swifts and no idea of where they would overnight. Also, as we were debriefing during our "congregation" at the Church, a chsw dove into the Church chimney about 15 min. post-roosting hour and then left a short time later!
Ruby and her flock of monitors had 36 swifts roosting in the tall Selkirk chimney, up from 25 the first night. Also, there were 7 entries then 2 exits in the red chimney; 5 swifts were in the site at the end of the roosting hour which left two chimney swifts unaccounted for in a roost site.
Two issues seem certain. First, available nesting territory is not immediately claimed at the onset of the season. Perhaps the 2013 breeding pair at the St. Adolphe Church are dead or late-arriving and the 2014 migrants are trying to sort themselves out for the current nesting season.
Second, we have solid data that chimney swifts may be airborne well after the roosting hour. Therefore, in-site roosting totals may underestimate the total number of birds in the immediate area. Another challenge for the number crunchers...
Elsewhere in Manitoba, David Dawson counted 2 chimney swifts roosting at La Broquerie. Don and Roxie Reimer are still waiting for the first arrivals at the Steinbach hospital. David first discovered that this site was active during last year's season, so we do not have historical information for the hospital chimney. There is hope though for migrants to appear this week or later in the season.
There can be new arrivals in St. Adolphe during the third week of June. These birds may be late arriving migrants from the south or re-dispersing local swifts that had arrived in May. The same thing may happen elsewhere in Manitoba. So even if sites are empty now, there is a possibility of occupation later. Any additional monitoring of "empty" sites during the third week of June would be appreciated!
Thursday, May 29th is the next target for the national blitz. I expect numbers to build in the roost sites in Selkirk and Dauphin. For other chimneys that may be nest sites, do not give up hope of seeing swifts if they have not been sighted to date. It has been a late spring and as we are at the northern periphery of the distribution range, migrants are still arriving.
The weather is improving to the point that bug smacking on the windshield is occurring at night now and those marvelous mosquitoes are starting to appear. Think of these insects as chimney swift food instead of pesky summer intruders!
I hope you all enjoy some bounty of birds on Thursday night. Another bulletin will be sent out to update you on the developments and trends. Your monitoring efforts are appreciated very much!
Cheers, Barb.
mbchimneyswift@gmail.com
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