president of the national police bloodhound association and as you can see right there, his blood hountwatson, is joining us as well. thank you so much for joining us. the dogs we've been told have been key in this investigation, in this manhunt so far. last week they said that they had a strong scent that they were on that could have been picked up by the dogs that were working to track these guys, but clearly nothing came of it. how long does a scent last? does that mean this trail has gone cold? >> well, it may have gone cold. it depends on a lot of factors as far as how much a scent will last. weather conditions, contamination within the search area. you know, wind conditions, things like that. so it's really left up to the dog as to what he's able to follow and what he's not. i mean, unless you try, you don't know whether he can pick up a scent or not. >> we've been told that guys like watson and his friends are very good, almost perfect in some cases in finding a scent if it is there. if you are one of these guys, a convict on the run, if you're trying to evade dogs like watson, w