Pacific Spiny Dogfish, Squalus suckleyi
Pacific Spiny Dogfish, Squalus suckleyi. Fish provided by the commercial fishermen of the greater Los Cabos area, Baja California Sur, July 2008. Length: 76 cm (2 feet 6 inches).
Pacific Spiny Dogfish, Squalus suckleyi. Display of unique finnage of this species.
Pacific Spiny Dogfish, Squalus suckleyi. Fish caught from coastal waters off Redondo Beach, California, November 2016. Length: 1.12 m (3 feet 8 inches). Catch, photograph, and identification courtesy of Ben Cantrell, Peoria, Illinois.
The Pacific Spiny Dogfish, Squalus suckleyi, is a member in the Dogfish Sharks or Squalidae Family, that is also known as the North Pacific Spiny Dogfish and the Spotted Spiny Dogfish and in Mexico as cazóne espinoso común. Globally, there are nine species in the genus Squalus, of which three are found in Mexican waters, two in the Atlantic and one, this species, in the Pacific Ocean.
The Pacific Spiny Dogfish has a slender cylindrical body. They are gray dorsally and white ventrally and usually have conspicuous white spots on their sides. Their head has a narrow pointed snout, eyes midway between the tip of the snout and the first of five gill slits, a short nasal flap with the inner corners of the nostrils being closer to the snout tip than to the mouth, and modest sized spiracles just behind the eyes. The teeth on their upper and lower jaws are low, blade-like, and of similar size with strongly oblique tips. They do not have anal fins; their caudal fin has a pair of keels and an angular notch separating the 2 lobes, but does not have a notched lower lobe; they have 2 dorsal fins, the first originating behind the pectoral fins; both fins have a single spine with the second dorsal spine being longer than the first dorsal spine; and their pectoral fins are narrow and sickle-shaped. Their skin is covered with small denticles that have three-points.
The Pacific Spiny Dogfish is found both near the surface in bays and estuaries and on the bottom in the open ocean at depths up to 1,372 m (4,500 feet). They reach a maximum of 1.6 m (5 feet 3 inches) in length. As of January 1, 2023, the International Game Fish Association world record stood at 5.67 kg (12 lbs 8 oz) with the fish caught from coastal waters off Tamales Bay, California in July 2018. They prefer waters between 7oC (45oF) and 15oC (59oF) and will make longitudinal and depth migrations to follow this temperature preference. Reproduction is ovoviviparous with offspring developing from eggs hatched within the female’s body and released alive into the ocean without placental attachment. The Pacific Spiny Dogfish is poorly studied with very limited information available about their lifestyle and behavioral patterns including specific details on age, growth, longevity, movement patterns, diet, habitat use, and reproduction.
The Pacific Spiny Dogfish is a resident of Mexican waters of the Pacific Ocean but has a limited distribution being found only along the west coast of the Baja.
The Pacific Spiny Dogfish cannot be confused with any other species due to the unique configuration of the spines of its 2 dorsal fins.
From a conservation perspective the Pacific Spiny Dogfish has not been formally evaluated and their long term viability as with all sharks is unknown. They is considered to be edible but are in very low demand. Larger individuals are reported to contain high levels of mercury.