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by Wes Nicholson This article originally appeared in the Bremerton Sun on March 23 under the title of "Rockfish present a bit of a mystery in NW". The article appears here with the kind permission of The Sun. I'm nose to nose with a small fish and I'm puzzled. Its large mouth, deep body and sharply pointed dorsal spines tell me it's a rockfish. But which one? There's no way to tell under water since the young of many species look alike. This is one of the many reasons that rockfish are so intriguing. Divers in Puget Sound often see one or more species of rockfish on each dive. Most often they are found near some type of rocky bottom and hence their name. Rockfish belong to the genus Sebastes, Greek for "magnificent" and a great name for this diverse group. Sixty-five rockfish species occur along the west coast, but only thirty-five live in Washington waters. Puget Sound divers commonly see only six. The other species live too deep or too far off shore to be encountered by divers. Rockfish range in size from seven inches to three feet and in coloration from white to black with every combination in between. Some live in shallow water while others inhabit the dark depths of the continental drop-off. Some are easy to identify while others puzzle rockfish experts. Unlike most fish, rockfish bear live young. Following birth, the larvae drift with ocean currents as they grow. After three to six months the juvenile rockfish search for the right habitat and abandon their planktonic life style. Rockfish belong to the scorpion fish family and have venom glands at the base of some of their fins. However, unlike some of their tropical cousins, their poison is mild and does not pose a risk to people. The number of poisonous spines and the strength of the venom vary between species. Rockfish are long lived. Small species have life spans of over twenty years, while larger species may reach one hundred years. (By comparison, salmon live only three to seven years.) Conditions in the sea are not always favorable for the survival of larvae. Thus, the longer a fish lives, the longer it has to take advantage of periods of favorable ocean conditions, for efficient reproduction. Many rockfish species have had important commercial and recreational fisheries. However, stocks of many species have declined due to a combination of a long period of unfavorable ocean conditions and high harvest rates. These declines have resulted in closure of the fisheries to let the stocks rebuild. Rockfish are an important part of the northwest marine environment; their survival is up to us. |
