| Country of origin: | Great Britain |
| Registries: | JRTCA, UKC |
| Occupation: | Hunter, performance sports |
| Size: | 10 to 15 in tall; 10 to 20 lbs |
| Longevity: | 14 to 16 years |
| Exercise: | Vigorous daily exercise |
| Training: | Moderate; hard to keep challenged |
| Grooming: | Easy |
| Colors: | Black and white, brown and white, tricolour |
Immensely popular in Britain, this breed was developed as a ratter in 19th-century Devon, England, by the Reverend John Russell, the “Sporting Parson”. It retains all of its terrier instincts, and is feisty and outgoing, generally exuberant and affectionate, but needing competent discipline to curb its more aggressive tendencies. Explorer Sir Ranulph Fiennes walked his Jack Russell to both the North and South Poles, testament to how much exercise these rugged little dogs crave. The waterproof double coat may be smooth- or wire-haired, the build is short-legged and muscular, and the long head has generally folded ears. As working dogs, Jack Russells originally had their tails cut short, a habit that persists in some breed registries. Until recently, the name “Jack Russell” was also used to describe the type now called the Parson Russell Terrier.