Man! I remember going to Canada back when Spring bear hunting was allowed and they had a May Fly hatch that looked just like that up on Horwood Lake (N. Ontario). We pretty much depended on catching Walleye to feed ourselves as we were out in the middle of nowhere at the far end of the lake from the fish camp (appx. 17 miles). It was TOUGH fishing as the fish were engorged on nymphs and just weren't feeding ... at least not on anything we presented to them. Running the boat was pure torture btw.