The American Bulldog descends from working bulldogs that came to the American South with early settlers and spent generations catching cattle and hogs and guarding farms. The breed nearly disappeared after World War II before John D. Johnson and Alan Scott revived it, which is why you'll see both a heavier, shorter-muzzled bully type and a leaner, more athletic standard type, plus plenty of dogs in between.
Adults weigh roughly 60 to 115 pounds and are mostly white, often with patches of red, brown or brindle. Many are devoted and affectionate with their people, confident, and watchful with strangers. In Seattle, that strength means a sturdy leash, a good harness, and early reward-based training before a big dog meets busy sidewalks and crowded trailheads. Dogs vary a lot, and many shelter dogs labeled American Bulldog are mixes.