Working terriers

A working terrier is a small type of dog which pursues its quarry into the earth. According to the Oxford English Dictionary, the name dates back to at least 1440, derived from French chien terrier 'digging dog', from Medieval Latin terrarius, ultimately from Latin terra (earth).

With the growth of popularity of fox hunting in Britain in the 18th and 19th centuries, terriers were extensively bred to follow the red fox, and also the Eurasian badger, into its underground burrow, referred to as "terrier work" and "going to ground". The purpose of the terrier is to locate the quarry, and either bark and bolt it free or to a net, or trap or hold it so that it can be dug down to and killed or captured.

Working terriers can be no wider than the animal they hunt (chest circumference or "span" less than 35 cm/14in), in order to fit into the burrows and still have room to maneuver. As a result, the terriers often weigh considerably less than the fox (10 kg/22 lbs) and badger (12 kg/26 lbs), making these animals formidable quarry for the smaller dog.

Terrier work has been condemned by British animal welfare organizations such as the League Against Cruel Sports, the International Fund for Animal Welfare, and the Royal Society for the Prevention of Cruelty to Animals, because it can lead to underground fighting between the animals, causing serious injuries. The British National Working Terrier Federation denies that underground fighting is an issue, arguing that the terrier's role is to locate, bark, and flush out the hunted animals, not to attack them. Hunting below ground with terriers is largely illegal in Britain under the Hunting Act 2004, unless conducted in accordance with strict conditions intended to protect game birds. Terrier work is legal in the US, Canada, Australia, South Africa, and much of continental Europe.

The primary criterion of a working terrier is that it has an owner or keeper who works it. A terrier is not a working terrier by virtue of its breeding alone. The second most important quality of a working terrier is small chest size. Though the chest size of the working terrier that can be used in any given situation may rise or fall depending on the size of the den pipe, smaller dogs generally do as well or better than larger dogs. The reason for this is rather simple: a small dog can get to the quarry without having to dig, and arrives at the quarry without fatigue.

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Wikipedia