Rainbow Seaperch

Rainbow Seaperch, Hypsurus caryi

Rainbow Seaperch (1)

Rainbow Seaperch, Hypsurus caryi. Fish provided by the commercial fishermen of the greater San Diego area, San Diego, California, October 2014. Length: 23 cm (9.2 inches).

Rainbow Seaperch, Hypsurus caryi. Fish caught from coastal waters off Angel Island, California, August 2021. Length: 23 cm (9.1 inches). Catch, photograph and identification courtesy of Luke Ovgard, Klamath Falls, Oregon.

Rainbow Seaperch, Hypsurus caryi. Fish caught from within San Francisco Bay, San Francisco, California, March 2020. Length: 25 cm (9.8 inches). Catch, photograph and identification courtesy of Chris Moore, Peoria, Arizona.

The Rainbow Seaperch, Hypsurus caryi, is a member of the Surfperch or Embiotocidae Family, that is also known as the Rainbow Surfperch and in Mexico as mojarra arcoiris. This fish is also commonly referred to as Embiotoca caryi in the scientific literature. It is the only global member in the genus Hypsurus, being found in Mexican waters of the Pacific Ocean.

The Rainbow Seaperch has a deep highly compressed elongated oval body with a typical “perch-like” shape and a depth that is 37% to 41% of standard length. They are one of the most beautiful fish in coastal northwest Mexico with red and blue stripes on their body and ten reddish-brown bars on their sides. Their anal and pelvic fins are reddish-orange with blue edges. They have dark spots on their anal fin and the soft portion of their dorsal fin. Their anal fin has 3 spines; their caudal fin is forked; and their dorsal fin has 9 to 11 spines and 19 to 28 soft rays and is continuous. They have 20 to 22 gill rakers. Their body is covered with small scales and the lateral line is complete.

The Rainbow Seaperch is found in shallow water along rocky shores, often at the edge of kelp beds, around piers, and occasionally over sandy terrain. They can be found in tidal pools, in the surf zone and to depths up to 50 m (165 feet). They reach a maximum of 31 cm (12 inches) in length. They feed on crustaceans, snails, and polychaetes worms. They are described as oral winnowers taking mouthfuls of sand and turf and selectively removing food and spitting out unwanted materials. Smaller fish act as cleaner fish consuming ectoparasites from each other and from other fish species. Reproduction is viviparous and occurs in large aggregations in the fall. Gestation lasts seven to nine months and young are born in shallower coastal waters. Each female produces nine to twenty-two fry in annual cycles that are 6.8 cm (2.7 inches) in length. Both males and females are of equal size.

The Rainbow Seaperch is a resident of Mexican waters of the Pacific Ocean but has a limited distribution being found from Guerrero Negro, Baja California, northward along the central and northwest coasts of Baja.

The Rainbow Seaperch is straightforward to identify due to its elongated body profile, face coloration, and the blue margin of its anal fin and is therefore not easily confused with any other species.

From a conservation perspective the Rainbow Seaperch has not been formally evaluated. They are caught in abundance off several piers in southern and northern California. They are fished on small hooks from the bottom utilizing mussels, pile worms or live rock crabs as bait. They are also caught by shore anglers in southern and central California but rarely caught by boaters. During spawning season they will enter tidewater areas where they are caught in abundance. They put up a strong fight for their small size. They are of insignificant importance as a food fish and normally a “catch and release” for all but subsistence fishermen. They are sold commercially on a limited basis in California.