Hi WDYS!
It's a controlled, rat-safe environment where the rats -which are what the dogs "hunt" - are in opaque, heavy-duty tubes hidden in and around bales of hay, usually in a barn or simulated barn environment. The activity is for all breeds and mixes but stems from Earthdog trials for Terriers, which were of course specifically bred to "go to ground" and kill small mammals. The rats in barnhunt are domestic rats as family pets and the dogs never physically touch them. The odg has so many minutes to find the rat and complete a set of exercises <"tunnel" through hay etc>. At the differnet levels of competition that search gets more complicated and may involve as many as 8 rats, or the handler doesn't know -how- many rats there are. Regardless of level, handler never knows where therats are and relays on dog to alert to rats, so a lot of this is being in partnership with your dog and learning how to tell taht your dog has a live rat as opposed to the-smell- of a rat. This is a link to a Barnhunt video with a Rottie:
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