There's a whole lot of "we're seeing more wild turkeys and fewer ruffed grouse". Biologists will usually tell you that's mostly a habitat issue: Woods more mature and OK for turkeys but not so much for grouse.

Don't think there's much of a relationship between turkeys and pheasants. Turkeys were well established when Iowa was regularly the top producing pheasant state in the nation. Likely there's some competition for food during harsh winters near good turkey habitat (woodlands). But in the Midwest, a lot of pheasants live in places you won't find many turkeys because there isn't enough forest nearby.