The two dogs involved in the fatal mauling of Diane Whipple last year were mastiff-Canary Island mixes.

Canary Island dogs, popularly called Presa Canarios, were developed in Spain to guard cattle for farming. "Presa" means prey; "Canario" means from the Canary Islands.

Breeders estimate there are no more than a few thousand in the United States. Males can weigh as much as 140 pounds, while females are in the 110-120 pound range. The dogs are about 27 inches tall at the shoulder, about the same height as a Doberman pinscher.

Properly trained, the breed is safe, experts say.