Migrating dragonflies over Brantford

[Bill Lamond]

Hello all,

On 21 August I was standing in the backyard at Carolina Park, Brantford (essentially my yard!) searching the trees and skies for birds. It was about 5 p.m. I noticed a few dragonflies high up heading WSW. I've seen dragonflies migrating before at this location, usually all Common Green Darners but often Black Saddlebags as well. Eventually the number of dragonflies grabbed my attention so I started to count them. Some were obvious darners (assumed to be CGDA) but there were some that looked like Gliders. I was getting a couple dragonflies a minute, but at times I would see a few darners at one time, all fairly close together as though moving together. Things really picked up around 6:30 when there was almost a swarm of darners high up, right overhead. Perhaps as many as 40 above me, most heading WSW but several milling about, although I think they all proceeded to move off in the same direction eventually. What was interesting, is that after this "swarm" went by, I only saw one more darner go by about 5 minutes later. I stopped looking at about 6:45.

I counted a total of about 180 dragonflies. The "swarm" was hard to count but I did what I could. I noted 4 Black Saddlebags in this period, and a few that looked like gliders. Also what appeared to be a few small dragonflies, that is meadowhawks or dashers, also moving with the others although not as high up. But judging size was problematic, but the style of flight, with a rapid change in direction reminded me of meadowhawks. I did see one meadowhawk go low over my head, in the same direction, although I was unsure if it was part of the movement. Also of note was one Twelve-spotted Skimmer that went over fairly high up migrating. You might not think that this species migrates but it certainly does as you can see many fly south of the Tp of Point Pelee on certain days in August.

I have no idea what weather would have caused this dragonfly movement. It was a hot enough day but I noticed in the late afternoon that the temperature was suddenly cooler and possibly a small cold front had moved through?

At any rate it was fascinating to witness.

Also of note were about 4-5 Monarchs fairly high up moving in a direction almost WNW. Not the typical direction I see Monarchs move over Carolina Park.

Bill