The only serious issue I have been aware of over the years at Tyler is deer poachers. The quality of the search depends on the experience of the searchers and their training. One of the big issues in SAR over the years is getting searchers to look up into trees etc and to look down in low lying spots, animal den's and drain pipes. Searchers also tend to go around very dense growth, branch tangles, deep overgrown gullies and obstructed spots. The thinking is that if they cannot get in there, the missing person could not have either. The quality of the dog alerts depends on what type dog was used, air scent or ground scent. If there is a scent going into the park, but not out, it could mean a) the person is still in the park, b) the person was taken out in a vehicle (no scent trail), c) the person is moving around to avoid being located and thus confusing the dog(s), or d) the scent trail has been contaminated.