Terrier Group. People familiar with this Group invariably comment on the distinctive terrier personality. These are feisty, energetic dogs whose sizes range from fairly small, as in the Norfolk, Cairn or West Highland White Terrier, to the grand Airedale Terrier.Terriers typically have little tolerance for other animals, including other dogs. Their ancestors were bred to hunt and kill vermin.Many continue to project the attitude that they're always eager for a spirited argument.hese are feisty, energetic dogs whose sizes range from fairly small, as in the Norfolk, Cairn or West Highland White Terrier, to the grand Airedale Terrier. Terriers typically have little tolerance for other animals, including other dogs.