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2010 January - Blue Sided vs Blue blotched Rockfish February - Northern Feather Duster Worm March - China Rockfish April - Opalescent Nudibranch May - Starry Flounder June - Eccentric Sand Dollar July - Great Sculpin

July 2010

photo© 2010 Janna Nichols

Great Sculpin
Myoxocephalus polacanthocephalus
Sculpin Family

Description: This large mouth sculpin has a long snout and a head that tapers down to its pectoral fin. It has four dark bars running downward along with a long smooth spine extending from its upper check along with variable patches and saddles.
Color: Primarily olive to gray in color, occasionally displays blotches of white to earth tones allowing it to blend into its environment.
Range: Bering Sea to Puget Sound and also to northern Japan.
Size: The Great Sculpin is as its name suggests is one of the largest sculpins encountered in the Pacific Northwest. The length of it reaches up to a maximum of 30 inches long, but typically runs between 14 to 20 inches.
Hangouts/Habitat: Sandy, silty and muddy bottoms of bays, wharves, pilings and jetties.
Depth: It is found in the intertidal zone to 800 feet.
Behavior: Hangs out on the bottom lying motionless looking for smaller fish to prey on. It ambushes it prey in this way when a meal is within its reach.
ID Clues: Identifying the Great Sculpin many times is confused with the similar looking Buffalo Sculpin. The more colorful Buffalo Sculpin has a rounder, bulbous head and is shorter in length.
Other Cool Facts: The Great Sculpin make "great" photo subjects, since they never seem to move unless provoked.

- Contributed by Todd Cliff, REEF PNW AAT, level 5

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June 2010

photo© 2010 Janna Nichols

Eccentric Sand Dollar
Dendraster excentricus
Echinodermata Phylum

Other names: Pacific sand dollar, west coast sand dollar, sea cookie
Description: Sand dollars are essentially flat sea urchins with extremely short spines. The outer "shell", called a test, is fairly circular in outline and has a five-petal flower pattern which is most obvious when the animal is dead and bleached. The pattern is formed from a series of pores from which tube feet extend in the living animal.
Color: Usually a very dark blackish purple; sometimes gray or dark brown.
Range: Found from Juneau, Alaska to northern Baja California, Mexico.
Size: Diameter to about 4 inches (100 mm).
Habitat: As the common name suggests, they live in sandy areas, usually in large aggregations. They are found both in exposed areas on the outer coast and in the fully protected, calm waters of southern Puget Sound.
Depth: Found from the mid-intertidal to nearly 300 ft (90 m).
Biggest enemy: Sand dollars are unpalatable to most predators. The ratio of edible tissue to skeleton is very low, and once the test is breached there are internal partitions that make it difficult to reach much tissue without a lot of additional effort. The giant pink star preys on them and sand dollars will quickly bury themselves when they smell this star.
Sunflower stars also eat them, graceful Cancer crabs often damage the edges of tests, and sea gulls will sometimes peck through the top of the test. California sheephead and starry flounder are known to feed on them, and there are some areas where they comprise a large part of the diet of wolf eels.
I.D. clues: This is the only sand dollar known to occur from northern British Columbia through central California. It can be distinguished from other species at either end of its range by the five-petal flower pattern on the test, which is off-center and asymmetrical instead of in the middle.
Cool facts: Dendraster is a filter feeder, standing on edge in the sand and capturing small organisms and particles of detritus from the water.
Larval sand dollars settle within adult beds for protection, and baby sand dollars selectively swallow heavier sand grains, probably to serve as a 'weight belt' to help them maintain position (divers - don't try this).

The density of adult beds can be astounding- over 500 per square yard- and there is a bed off Long Beach on the Washington coast that is over 20 miles long.

- Contributed by Dr. Greg Jensen, REEF PNW AAT, level 5

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May 2010

photo© 2010 Janna Nichols

Starry Flounder
Platichthys stellatus
Right Eye Flounder Family

Other Names: Grindstone, Leatherjacket, California or Diamond Flounder
Description: One of the easier flatfish to identify, the Starry Flounder has a series of prominent dark bands on the dorsal, anal & tail fins. It has an oval shaped body and a slightly rounded tail.
Color: Shades of brown and gray. The bars are dark alternating with cream/yellow/orange.
Range: Southern CA to the Arctic coast. Also from the Bering straight to Southern Japan.
Size: Generally 1' - 2 1/2', max is 3 feet & 20 lbs
Hangouts/Habitat: Mud/silt/sand bottoms, often hangout near eelgrass beds.
Depth: 0 - 1,200' but they typically are found shallow in the 0 - 150' range.
Behavior: Tends to live on the bottom, often partially or completely covered with sand/silt/mud. Juveniles can be found in the intertidal zone.
ID Clues: The bars are the biggest clues, right vs. left sided is not necessarily a good clue. Also look for starry shaped rough plates on the eyed side of the fish.
Other Cool Facts: Even though this is in the "right eyed flounder" family, it isn't always "right eyed"! In the local area - on the coasts of Washington, Oregon and California - there is a 50 - 50 split of right/left eyed. In the area around Alaska, the split is 70/30 right to left..... in Japan, they are ALL left eyed! In other words, look at the other ID clues as right vs. left eyed can mislead you on this one.

- Contributed by Heidi Wilken, REEF PNW AAT, level 5

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April 2010

photo© 2010 Peter Mieras

Opalescent Nudibranch
Hermissenda crassicornis
Mollusca Phylum

Scientific name: Hermissenda crassicornis
Common name: Opalescent nudibranch
Other names: Horned Aeolid, Opalescent sea slug, opalescent aeolid, (thick or long) horned nudibranch, long horned hemissenda, hermissenda nudibranch.
Description: This nudibranch has usually bright cerata that have orange and white bands. In some variety the cerata are more dull brown with white tips or white stripes run up the cerata. In the middle of the dorsum (back) bright orange highlights occur and a blue line can be observed at the dorsal surface of the oral tentacles. A similar thin pale blue line can be seen around the base of the body.
Range: Sea of Japan, from Alaska down to Mexico
Size: mostly around 1-2"(25-50mm) but occasionally up to 3" (75mm)
Hangouts/Habitat: The opalescent nudibranch prefers rocky areas or hard substrate in general. Since it feeds on hydroids and other aeolids you can find this species in areas where hydroids are common.
Depth: intertidal to ± 110 feet (36 meters)
Behavior: Feeds on hydroids by grazing with its radulae ( a file like structure, that consists of many chitinous teeth). Usually fairly static but can move with surprising speed if need to.
Biggest Enemy: Sunflower starfish and other opalescent nudibranch
ID Clues: orange white banded cerata, typical pale blue colour on the top of the front tentacles
Other Cool Facts: Member of the suborder Aeolidina, named after the Greek god of the wind Aeolius. The cerata contain nematocysts ( stinging cells) collected from the hydroids and sea anemones they feed on. When they collect the immature stinging cells they pass them unharmed through their digestive system to the tips of their cerata. Here the stinging cells mature and are used for the defence of the nudibranch.
Opalescent nudibranchs are aggressive fighters. When two of them meet head-to-head, they're likely to get into a biting battle. If one meets the tail of another and gets the first bite, it usually wins the battle and eats the loser.

Because opalescent nudibranchs live less than one year, they have to grow and reproduce quickly-they can't lose time looking for a mate. A meeting between two or more can be a mutual mating session, since these creatures are hermaphroditic (they have both male and female sexual organs). Later, each lays an egg string in narrow coils that looks like tiny sausage links. They attach their eggs to eelgrass and algae.
Large fluctuations in the population due to the availability of their food source are observed. This particular species is a popular subject for underwater photographers and videographers.

More info at: http://www.scholarpedia.org/article/Hermissenda#General_Information

- Contributed by Peter Mieras, REEF PNW AAT, level 5

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March 2010

photo© 2010 Jeanne Luce

China Rockfish
Sebastes nebulosus
Scorpionfish Family

Other Names: Yellowstripe Rockfish, Yellowspotted Rockfish
Description/Color: Bluish black to black with yellow spots and blotches.
Range: Common southeast Alaska to California; occasional to rare northern and central California
Size: 8-14 in, max 17 in
Hangouts/Habitat: Rocky inshore areas along exposed coastlines. Lurk in caves and crevices.
Depth: 12-400 ft
Behavior: China Rockfish generally rest on bottom propped up by their fins. When away from hole, they swim near bottom. Solitary. Their territories are apparently small, with a study off Vancouver Island finding Chinas moving only within 10 m (33 ft). They feed on benthic organisms, including brittle stars, chitons, and crustaceans such as crabs and shrimp. Unafraid and curious; china rockfish often allow close view when approached with slow nonthreatening movements.
Biggest Enemy: Humans. This species of rockfish, like many others, has a declining wild population as they are highly esteemed as one of the tastiest rockfish. They have been popular for commercial fishing since the 19th century. During the 1930s, Chinas sold for twice as much as any other rockfish except the black-and-yellow rockfish, and for more than any other kind of finfish. They are today popular in Asia, often being sold alive.
ID Clues: Yellow speckles on head and body, yellow "swoosh" from foredorsal fin that curves to run length of lateral line to tail.
Other Cool Facts: The species epithet nebulosus is Latin for "clouded". Although Jordan and Evermann promoted the common name "yellowspotted rockfish", the "China" name has persisted, due to a perceived preference by persons of Chinese ancestry living in central California.

- Contributed by Jeanne Luce, REEF PNW AAT, level 5

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February 2010

photo© 2010 MaryJo Adams

Northern Feather Duster Worm
Eudistylia vancouveri
Annelida Phylum

Name: Northern feather duster worm
Other names: Plume worm, parchment tube worm
Description: Polychaete worms inhabiting leathery or parchment appearing tubes and extending to form plumes with feather duster appearance. This species often forms large aggregations but may also be found as solitary individuals.
Color: Plume has alternating bands of maroon and dark green
Range: Alaska to California
Size: Tubes reach a length of 24 inches and diameter of ½ inch. The plume is up to 2.4 inches in diameter.
Hangouts/Habitat: Found on floats, pilings, and rocky areas.
Depth: Intertidal to 100 feet
Behavior: Has light sensing structures and if a shadow falls across it, the plume will zip back into its tube in the blink of an eye.
ID clues: There are other similar appearing sabellid tubeworms with parchment like tubes and feathery plumes so look for tubes with a diameter slightly larger than that of a pencil and the maroon/dark green banding on the plumes.

- Contributed by Mary Jo Adams, REEF PNW AAT, level 5

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January 2010

Photo one:
photo© 2010 Janna Nichols

Photo two:
photo© 2010 Janna Nichols

Blue Rockfish for both
Sebastes mystinus and ??
Scorpionfish Family

Description: It's a two-for-one special this month! Scientists have become aware that there are TWO species of what has been commonly called the Blue Rockfish. They are in the process of describing and naming the two species now. REEF divers are needed to help determine the ranges/depths, etc. of these two species. For REEF surveys, we're calling the fish shown in Photo #1 a Blue Sided Rockfish, and Photo #2 depicts a Blue Blotched Rockfish.
More info: http://www.reef.org/enews/articles/when-blue-not-blue
Color: Both are bluish gray with forehead stripes
Range: Northern Baja to Southern Alaska. I have seen the Blue Blotched Rockfish when diving in Monterey, California, and the Blue Sided when diving in Washington and BC. Other divers have seen both occur in Oregon. Fishermen are finding both species in many areas.
Size: Up to 21" long. Usually up to 18".
Hangouts/Habitat: In Monterey, California area, I've seen schools of Blue Blotched Rockfish hanging out in the kelp in midwater. In Neah Bay and up into BC, I've seen Blue Sided Rockfish always intermixed in schools of Black Rockfish, hanging out in kelp forests or near kelpy areas.
Depth: I usually see both schooling in less than 40 feet of water, but can be found to depths to 300 feet.
Behavior: Both appear to be schooling fish and will allow a closer look if you watch your buoyancy and move slowly. Let them come to you by staying very still.
Growth: Grow to be about 40 years old. Males and females are sexually mature at about 10 years old (about 14" long at that age). Females are larger than males at any given age.
Comments: Blue Rockfish stay in one specific area their entire lives. They can be easily overfished by partyboats, private vessels and spearfishers.
I.D. Clues: Look for the stripes on the forehead on both species.

Blue Blotched:

Blue Sided:

- Contributed by Janna Nichols, REEF PNW AAT, level 5