The kelp greenling (''Hexagrammos decagrammus'') is a species of marine

ray-finned fish Actinopterygii (; ), members of which are known as ray-finned fish or actinopterygians, is a class of bony fish that comprise over 50% of living vertebrate species. They are so called because of their lightly built fins made of webbings of sk ...

belonging to the

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

Hexagrammidae Hexagrammidae, the greenlings, is a Family (biology), family of marine ray-finned fishes belonging to the suborder Cottoidei in the Order (biology), order Perciformes. These fishes are found in the North Pacific Ocean. Taxonomy Hexagrammidae wa ...

, the greenlings. It occurs in the eastern Pacific Ocean

Species description and etymology

The kelp greenling was first formally described in 1810 as ''Labrax decagrammus'' by the German

naturalist Natural history is a domain of inquiry involving organisms, including animals, fungi, and plants, in their natural environment, leaning more towards observational than experimental methods of study. A person who studies natural history is cal ...

Peter Simon Pallas Peter Simon Pallas Fellow of the Royal Society, FRS FRSE (22 September 1741 – 8 September 1811) was a Prussia, Prussian zoologist, botanist, Ethnography, ethnographer, Exploration, explorer, Geography, geographer, Geology, geologist, Natura ...

with its type locality given as Cape St. Elias in

Alaska Alaska ( ) is a non-contiguous U.S. state on the northwest extremity of North America. Part of the Western United States region, it is one of the two non-contiguous U.S. states, alongside Hawaii. Alaska is also considered to be the north ...

. The

specific name Specific name may refer to: * in Database management systems, a system-assigned name that is unique within a particular database In taxonomy, either of these two meanings, each with its own set of rules: * Specific name (botany), the two-part (bino ...

, ''decagrammus'', means "ten lines" refers to the 5

lateral line The lateral line, also called the lateral line organ (LLO), is a system of sensory organs found in fish, used to detect movement, vibration, and pressure gradients in the surrounding water. The sensory ability is achieved via modified epithelia ...

canals on each flank, giving a total of 10.

Description

Kelp greenlings 21 or 22 spines in their first

dorsal fin A dorsal fin is a fin on the back of most marine and freshwater vertebrates. Dorsal fins have evolved independently several times through convergent evolution adapting to marine environments, so the fins are not all homologous. They are found ...

and 24 soft rays in their second dorsal fin while the

anal fin Fins are moving appendages protruding from the body of fish that interact with water to generate thrust and help the fish swim. Apart from the tail or caudal fin, fish fins have no direct connection with the back bone and are supported o ...

contains a single spine and 23 or 24 soft rays. The males are gray to brownish olive in color, dotted with irregular blue spots over the anterior half to two-thirds of their body. Each of these spots has a ring of small rusty spots around it. The females are also gray to brownish in color but they are marked all over with rust colored or golden spots. They have yellowish orange fins. In both males and females the inside of the oral cavity is yellowish and there is frequently and eye-like spot, an ocellus. at the rear of the second dorsal fin. There are five lateral lines on each flank, as well as a fleshy cirrhi over the eye with another halfway between the eye and the origin of the dorsal fin. This species has a maximum published

total length Fish measurement is the measuring of individual fish and various parts of their anatomies, for data used in many areas of ichthyology, including taxonomy and fishery biology. Overall length Standard length (SL) is the length of a fish measured f ...

of and a maximum published weight of .

Distribution and habitat

The kelp greenling is found in the eastern pacific Ocean where its range extends from the

Aleutian Islands The Aleutian Islands ( ; ; , "land of the Aleuts"; possibly from the Chukchi language, Chukchi ''aliat'', or "island")—also called the Aleut Islands, Aleutic Islands, or, before Alaska Purchase, 1867, the Catherine Archipelago—are a chain ...

of Alaska to

La Jolla La Jolla ( , ) is a hilly, seaside neighborhood in San Diego, California, occupying of curving coastline along the Pacific Ocean. The population reported in the 2010 census was 46,781. The climate is mild, with an average daily temperature o ...

southern California Southern California (commonly shortened to SoCal) is a geographic and Cultural area, cultural List of regions of California, region that generally comprises the southern portion of the U.S. state of California. Its densely populated coastal reg ...

. This species occurs in rocky nearshore areas of the northern is common on kelp beds and on sand bottoms.

Biology

Kelp greenlings feed on

crustacean Crustaceans (from Latin meaning: "those with shells" or "crusted ones") are invertebrate animals that constitute one group of arthropods that are traditionally a part of the subphylum Crustacea (), a large, diverse group of mainly aquatic arthrop ...

polychaete worm Polychaeta () is a paraphyletic class of generally marine annelid worms, commonly called bristle worms or polychaetes (). Each body segment has a pair of fleshy protrusions called parapodia that bear many bristles, called chaetae, which are ma ...

brittle star Brittle stars, serpent stars, or ophiuroids (; ; referring to the serpent-like arms of the brittle star) are echinoderms in the class Ophiuroidea, closely related to starfish. They crawl across the sea floor using their flexible arms for locomot ...

mollusk Mollusca is a phylum of protostomic invertebrate animals, whose members are known as molluscs or mollusks (). Around 76,000 extant species of molluscs are recognized, making it the second-largest animal phylum after Arthropoda. The ...

s, and small fishes. The young are food for large predators such as

steelhead Steelhead, or occasionally steelhead trout, is the Fish migration#Classification, anadromous form of the coastal rainbow trout or Columbia River redband trout (''O. m. gairdneri'', also called redband steelhead). Steelhead are native to cold-wa ...

and

salmon Salmon (; : salmon) are any of several list of commercially important fish species, commercially important species of euryhaline ray-finned fish from the genera ''Salmo'' and ''Oncorhynchus'' of the family (biology), family Salmonidae, native ...

. Unique to this species is its mating ritual, where males attempt to inseminate eggs in the nests of other males. This phenomenon can be explained with condition dependent mating decisions.

Fishing

This species is frequently caught by hook and line, fishing from shore or skiff, as well as speared by divers. They are commonly caught by fishermen targeting other species, and are often viewed as pests, despite their scrappy fight and tasty flesh. They are easily caught around rocky cliffs and kelp beds, and respond to a wide variety of natural and artificial baits.

References

External links

Hexagrammos decagrammus at Fishbase
{{Taxonbar, from=Q2378626 kelp greenling Fish of the Pacific Ocean Fauna of Alaska Fauna of Western Canada kelp greenling Taxa named by Peter Simon Pallas