Rainbow Seaperch, Hypsurus caryi
The Rainbow Seaperch, Hypsurus caryi, whose common Spanish name is mojarra arcoiris, is a member of the Surfperch or Embiotocidae Family, known collectively as mojarras viviparas in Mexico. This fish is also commonly referred to as Embiotoca caryi in the scientific literature. There is only one global member in the genus Hypsurus, the fish described herein, which is found in Mexican waters of the Pacific.
The Rainbow Seaperch have deep highly compressed elongated oval bodies 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 is continuous with 9 to 11 spines and 19 to 28 soft rays. Their lateral line is complete and their body is covered with small scales.
The Rainbow Seaperch are found in shallow water along rocky shores, often at the edge of kelp beds, around piers, and occasionally over sandy terrain. The Rainbow Seaperch are found in tidal pools and in the surf zone at depths up to 165 feet. They reach a maximum length of 31 cm (12 inches). 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 9 to 22 fry annually that are 6.8 cm (2.7 inches) in length. Both males and females are of equal size.
In Mexican waters the Rainbow Seaperch have a limited distribution in being found from Guerrero Negro 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.
The Rainbow Seaperch 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.