Why do they bob the tail of a Jack Russell terrier?

Animal Artwork is right. The Jack (and now the Parson) Russell Terrier are earth dogs. Terriers have been used to hunt out game that burrows. When the dogs get into the burrow and grab hold of the game with their teeth, the hunter/owner would use the stumpy tail to back the dog out of the burrow with game in mouth. If the tail were left natural, the chances of the skin being slipped off the tail (a degloving injury) is increased.

That short stocky tail (when its bobbed) makes a great handle for pulling a dog out of a rat hole. If it were not bobbed the handler might grab the end of the tail where it is not so stocky. Plus a longer tail is more likely to be damaged going through burrows.

Edit: JRT's also dig like demons.. thus allowing them to get into rat holes... damned useful on a farm. Not all rats are "quarter sized".. there are some the size of a woodchuck...And yes, a degloving injury can happen to a dog whose tail is pulled for whatever reason. Point is, they are docked so they will serve safely as a handle.

Aren't they born like that? I just got a jack russell puppy and all of her siblings tails were bobbed.

Great Question! Jack Russels were officially trained to hunt rats and other small game, and they didn't want the dogs to get their tail caught on anything in rat holes.

jack russells are bred especially to hunt foxes. foxes dig in deep and the jacker chases it down the hole. sometimes jack will not come back out without its quarry so the bobbed tail is easy to catch and pull.this also applies to other animals it chases down holes.

There is no need for a dog to have its tail bob. Some people think it looks good that all its for. In more and more country's its out lawed and about time too.

When they were first breed, the hunters didn't want them getting caught in ropes or wire fences, so it's become a natural look to JRT all over. It's recommended in the AKC championships.