For the last 30 years farmers in the Texas panhandle would swear to me that their pheasants would have a second hatch, in wet El Nino spring and summers.
These are hard working responsible citizens, you just can't dismiss their observations as old wives tales. The farmers would notice chicks in June and again in August. One can only assume that that those are re-nesting hens with late clutches and not second hatch hens.
Histograms are just guides that depicts the peak hatch, based on field observations, of course it would occur in the first part of June in prime pheasant country.
We are still learning new things about these great bird, the truly wild pheasant, I would call them a work in progress.
I was also skeptical of their report of a second hatch. But when I read the 2001 publication "Experimental Pheasant Restoration Project" which documented Double-Brooding second hatch, on radio tagged hens, I quickly became a believer.
All this means is that the farmers were partly right and on the right track from the start.