Game birds are animals and don't see how anyone could upland hunt and not lose a bird now and then. Seems like that would be an impossible feat. Same could be said for squirrel and all sorts of other critters. But this is a Big Game forum so I guess that doesn't count.
For big game, I've experienced losing game to being eaten by predators after waiting a period of time before starting a track. Recovered the remains, but for all practical purposes, lost the animal.
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