The biggest impact with overpopulation isn't noticed until a couple years down the road when shrubs and natural forages are decimated. Of course then deer start leaving and dying off. Once that happens it can take years and years for a habitat to recover fully even with proper land management.
I hunt near some guys that subscribe to the more deer is better philosophy. They figure more does means more bucks later. The problem is, it just doesn't work like that for a ton of reasons. But I don't think I'll be convincing them any time soon

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