| China rockfish | |
|---|---|
 | |
| Sebastes nebulosus in Neah Bay, WA | |
Scientific classification | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Actinopterygii |
| Order: | Perciformes |
| Family: | Scorpaenidae |
| Genus: | Sebastes |
| Species: | S. nebulosus |
| Binomial name | |
| Sebastes nebulosus Ayres, 1854 | |
| Synonyms[1][2] | |
TheChina rockfish (Sebastes nebulosus), theyellowstripe rockfish[1] oryellowspotted rockfish,[3] is aspecies of marineray-finned fish belonging to the subfamilySebastinae, the rockfishes, part of thefamilyScorpaenidae. It is native to the waters of the Pacific Ocean off western North America.
The China rockfish was first formallydescribed in 1854 by the AmericanzoologistWilliam Orville Ayres with thetype locality given asSanta Barbara andMonterey, California.[2] Some authorities place this species in thesubgenusPteropodus.[4] The specific namenebulosus means "cloudy" a reference to the yellow body mottled with dark brown.[5] The species was actually described by both Ayres and Girard in the same year, with Girard naming the speciesS. fasciatus, but it was thought that that name had already been used for theAcadian redfish byDavid Humphreys Storer and thus Ayres' choice prevailed.[2]
The China rockfish has a compact body[6] with a small mouth.[7] They have a concave intraorbital space and robust spines on the head but there are none above the eyes.[6] Thedorsal fin has deeply incised membranes between its long spines,[8] there are 13 spines and 13 or 14 soft rays in the dorsal fin while theanal fin has 3 spines and 6 to 8 soft rays. Theircaudal fin is rounded. This species attains a maximumtotal length of 45 cm (18 in) and a maximum published weight of 1.7 kg (3.7 lb).[1] The overall color may be blue or black, marked with yellow mottling which is mixed with some white mottling.[6] The main distinguishing feature of this species is the clear yellow stripe which starts on the dorsal fin near the third dorsal fin spine and extends obliquely to thelateral line then runs along that line to make a shape like anice hockey stick.[9] Thepelvic, anal and caudal fins are dark colored.[1]
The China rockfish is found in the eastern Pacific Ocean off the western coast of North America fromKodiak Island in Alaska toRedondo Beach andSan Nicholas Island inCalifornia. It is at its most common from centralBritish Columbia south to central California.[9] It is associated with reefs at depths between 3 and 128 m (9.8 and 419.9 ft) but it is typically found in water less than 92 m (302 ft) deep.[1]
The china rockfish is a solitary andterritorial species and if alarmed they will quickly take shelter in a cavity or crevice in the reef. They are known to live for up to 79 years and they become sexually mature when they reach a total length of around 30 cm (12 in). They areovoviviparous and the females extrude the larvae in January to August.[9] The pelagic larvae leave the plankton to settle between one and two months after being born.[10] The spines in the dorsal and anal fins are mildlyvenomous[1] but are also used to wedge the fish in narrow hiding spaces in the reef.[8] The China rockfish is a sedentary species and studies have shown they rarely move more than 10 m (33 ft) from their preferred shelter. They have been known to live in the same rock crevices as theGiant Pacific octopus (Enteroctopus dofleini).[6] The larvae feed on plankton and the juveniles prey largely on crustaceans. The adults also eat crustaceans but also prey onbrittle stars, mollusks, and small fishes. The predators of the juveniles are sea birds, porpoises, and other fishes, including rockfishes,lingcod,cabezon andsalmon. The adults are preyed on by sharks, dolphins, seals, lingcod, and possiblyNorth American river otters (Lontra canadensis).[10]
China rockfish are an important component of the live fish fishery. There has been no formal stock assessment for this species[10] and it is managed as a species within the Nearshore Rockfish group regulated by thePacific Fishery Management Council.[11] Commercial fishing methods includehook and line,longline, andtrapping.[10] It is also important as a recreational fishing quarry.[11]
Astock assessment of China rockfish conducted in 2015 estimated the stock to be at 28% of unfished level inCalifornia, but less depleted inOregon andWashington, at 62% and 73%, respectively. However, the stock in California waters (which only included the area up toCape Mendocino) was estimated as showing an increasing trend in abundance, as this area had seen larger reductions in catch than the other areas.[12]
Media related toSebastes nebulosus at Wikimedia Commons