Offline
From what I've read, the earliest Black Flies can really become noticeable is the last week of May. Am I mistaking?
We planned a trip starting on May 6th but it looks like we'll have an early ice out. Will we be swarmed by black flies?
Offline
It's all about water temps in moving, well oxygenated water. 5C - 10C. I've seen them bad earlier than the last week of May countless times over the years.
Offline
An early ice out would most likely mean the bugs would be out earlier too! However, there is also a tendency for things to regress towards the norm. So for example if ice out was three weeks earlier than normal it doesn't follow that the bugs will be out three weeks earlier than normal and warm summer swimming conditions three weeks earlier than normal. Remember a few years back when the ice went out at the beginning of April? We got more typical April weather after that ice out and the bugs came out one or two weeks early but certainly not four weeks early.
Offline
As MSR said, blackfly emergence is most directly determined by water temps.
To give you some hope though, even in 2012 when ice out was March 25th for Canoe Lake the black flies were really not active the first weekend in May. We may have had a few, but that's not much for black flies.
Offline
Thanks everyone!
RobW, that is exactly what I wanted to hear. Thank you.