The Jack Russell Terrier is named for Reverend John Russell, a Devon parson in the 1800s who developed white terriers that could keep pace with hounds and bolt foxes from their dens. Today's dogs are compact and mostly white with black or tan markings, about 10 to 15 inches tall and 13 to 18 pounds, with smooth, broken or rough coats.
Many are bold, clever and funny, with a strong prey drive and a talent for digging, climbing and escaping. In Brooklyn, that means a secure harness, a firm grip on the leash around squirrels and pigeons, and daily training. Shedding is moderate to high, and rough coats may need occasional hand-stripping. Dogs vary, so a Jack's own energy and history matter more than the label.