Spiny dogfish inhabit colder waters of the Atlantic and Pacific oceans from shallows to nearly 700 metres (2,300 feet) deep. Found in all the world’s temperate oceans, the spiny dogfish is a small schooling shark that forms groups of hundreds, or thousands, of individuals of the same sex and size. The average length is between 75 and 105 cm (30 to 40 inches), however, individuals have been known to grow to 130 cm (50 inches) weighing 9 kg (20lbs).
Spiny dogfish sharks are long-distance travelers. One spiny dogfish tagged and released from Washington State showed up off the coast of Japan ~ a 8,046 kilometer (5,000 mile) ocean journey!