I had read that chick strength and survival were better in spring...
That has not been my personal experience... I see absolutely ZERO difference between my winter or spring hatched chicks... that I have quantified yet... but it's worth taking a DEEPER look into.
I agree that in NATURE that is the way... There need to be more spring chicks to feed the spring hawklings and such... but here my birds do have access to same abundance of feed all year long... I have broody's in the breaker ALL winter long. I don't have to keep them in a box, my pasture is green and bugs are EVEN more abundant than in summer and they can warm up under broody's, should that be the route I choose.
Indeed people do have different environments, set ups, and ideas.
But I did NOT miss out on part that is TRUE for SOME flocks in your first post... that fertility CAN be lower this time of year!
I only ask because I remember reading that after a period of time that evidence may not still be left but somehow degraded and re absorbed to look like nothing ever happened... so I was just curious, as I am here to learn. Doesn't sound like that was your issue at all.
Giving that this person does show with several years of experience with the same breed... and you DID discuss fertility and had a reasonable expectation of "good" fertility... I hope that when you approach kindly you will get a satisfactory resolution! Have you thought about what that might be?
Hoping for 100% hatch rate of all that were fertile!

