Pacific NW Marine Life - Critter of the Month Archives

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2011

January - Puget Sound Rockfish
February - Invasive Club Tunicate, Styela clava
March - Chimney Sponge
April - Pacific Staghorn Sculpin
May - Didemnum vexillum, invasive tunicate
June - Roughback Sculpin
July, Aug, Sept (no critter these months)
October - Manacled Sculpin

October 2011

Manacled Sculpin
Synchirus gilli
Sculpin Family

Description: Slender, tapered elongated body, generally with seven whitish blotches on the back and several smaller spots below the lateral line. Pointed snout. The pectoral fins join on the underside.
Range: Occasional southeastern Alaska to southern California. Can be locally common in kelp beds.
Size: 1- 1/2 inches. Maximum 3 inches.
Habitat: Inhabit areas of kelp, sea lettuce, and other leafy algae. Also in tide pools, floats of seaweed and on dock pilings. They like to rest on leaves, changing color to blend almost perfectly with background. Depth done to 80’.
Behavior: They dart from leaf to leaf. Wary and dart away when closely approached.

- Contributed by Georgia Arrow, REEF PNW AAT

June 2011

Roughback Sculpin
Chitononotus pugetensis
Sculpin Family

The Roughback sculpin, Chitononotus pugetensis is the only species in its genus. Chitononotus, is Greek meaning tunic back referencing its signature design forward dorsal. Although its species name is pugetensis its population range is from Northern British Columbia to Baja California.

Its morphology is of the typical sculpin family Cottidae; tadpole body shape with a big spiny head, bulbous eyes and fanned pectoral fins. Other characteristic combinations that help distinguish this species are; big lips and mouth and continuous scales from the dorsal fin to the lateral canal. Although it has the two separate dorsal fins, it may appear as if there are three because the forward dorsal has a unique double sloping ridge giving two distinct formations to the forward dorsal. The rear dorsal is evenly symmetrical.

Large dark saddle markings are separated by mottled lighter sections varying in color, from sandy beige/white to a silty tan brown with a tinge of green allowing the species to blend in well with their habitat. The fins are transparent with opaque rays that may display dark bar markings. Sometimes, the forward dorsal may have a dark edge outlining its unique shape which makes it easy to recognize. During courtship males often display an extra flare of color especially above their eyes appearing like one thick solid patch unibrow varying in the color array of red to white to orange.

Adult sizes range from 4 inches" to 7 inches. Younger ones often have a taller first spine with a more drastic steep slope using the first three spines creating a cleft in the forward dorsal. As they get older the slope becomes gradual, however the notch remains noticeable maintaining the double ridge appearance.

Their preferred habitats are soft substrates, sand, silt or mud, that may . Being a bottom fish they are often found partially buried in the sand or resting on top of the sand. They are spurt swimmers. When aroused they will dart about and then settle back down on the sand. Although they can be seen during the day they are more active at night. Normally, they live between 25 and 465 feet, enjoying a diet of shrimp and other crustaceans. As a result they are a trawler bycatch. Their salmon colored eggs can be found on the sand, attached to a tubeworm or stick.

The Roughback is hard to confuse with other sculpins, however the closest sculpin might be from the genus Icelinus - the Threadfin sculpin and the Spotted sculpin. Both can be found in same habitat and have similar behavior however all three have their own distinct dorsal design.

- Contributed by Rhoda Green, REEF PNW AAT

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May 2011

Critter of the Month photo - by Lorne Curran
photo© 2011 Lorne Curran

Invasive Didemnum tunicate
Didemnum vexillum
Urochordata phylum

This "vexing" species ranks high on the watch list of invasive sea squirts-invertebrates that can smother native organisms and block groundfish from their prey. Colonies have many small individuals called zooids within the protective matrix of a common tunic. Shown here overgrowing the native Northern Feather Duster Worm.
Common Names: D. vex for short. A recent infestation in Sitka, Alaska, prompted the moniker Rock Vomit.
Identification: In calm waters, thick masses meters across hang in irregular lobes. In current and surge, colonies thinly cover substrate sporting only short finger-like projections.
Look for: Random small openings to the zooids in a tan, cream, or yellow to orange tunic. Dark channels run from groups of zooids to larger excurrent openings.
Ecology: Found on hard artificial surfaces like docks, ship hulls, aquaculture gear. In natural habitat, it overgrows rock and gravel seabeds, seaweed and shellfish. Low intertidal to 80 m. From Japan.
Invasions: From California to Alaska, New England and Atlantic Canada. Worldwide: New Zealand, United Kingdom, the Netherlands, France, and more.
Similar Species: Invasive botryllid sea squirts come in orange, yellow, red, or purple, with zooids arranged in a distinct pattern. Sponges and bryozoans lack the dark channels of D. vex. Native Didemnum carnulentum is limited to a uniform white to gray with tinges of pink and no dark channels.

- Contributed by Lorne Curran, REEF PNW AAT

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April 2011

Pacific Staghorn Sculpin
Leptocottus armatus
Sculpin Family

Other Common Names: staggy or staggies
Description: gray to grayish-olive, dark spot on latter portion of first dorsal fin, lateral line nearly straight. Large, flat head, gill covers extend into antler-like projections with 3-4 spines.
Range: common to occasional Bering Sea to Southern California. Not often noticed as they tend to lay low in the sand
Size: 5-14 inches, max noted 18 inches
Hangouts/Habitat: sandy, silty, rubbly bottom. Often dig themselves into the bottom with only eyes or part of their head peering out (look at the sandy bottoms where "nothing" lives).
Depth: sighted more often in shallow waters, but can live below recreational dive limits.
Likes to munch on: fish, crustaceans and invertebrates
ID Clues: dark spot on rear portion of first dorsal fin. Often mistaken for Plainfin Midshipman, another sandy bottom dweller
Other Facts: Staggies usually will lie still in the silt and tend to be found more at night in shallow waters. Maximum reported age is 10 years.

- Contributed by Valerie Lyttle, REEF PNW AAT

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March 2011

Chimney Sponge
Staurocalyptus dowlingi and Rhabdocalyptus dawsoni
Porifera Phylum

Other Names: Round Lipped Boot Sponge, Sharp Lipped Boot Sponge, Boot Sponge
Description: There are actually two species commonly known as "Chimney Sponge". Both species look large and chimney like, with dark exteriors and light interiors, though the tops will look slightly different between species. Fortunately, both species can be listed as "Chimney Sponge" on REEF surveys, so you don't have to stress too much about telling them apart. The Round Lipped Boot Sponge has a relatively wide opening at the top and a rounded lip. The Sharp Lipped Boot Sponge generally will have a smaller opening and the white smooth inside will not extend out of the center of the sponge.
Color: Light/Whitish on the inside, generally Brownish on the outside.
Range: Southern California to Central Alaska.
Size: Max of 5' tall and ~ 3' across.
Hangouts/Habitat: They can be found attached to solid surfaces, either to individual rocks, or often on rock walls.
Depth: The Round Lipped species has been recorded from the subtidal to
3000+ feet. The Sharp Lipped species extends until 1600+ feet of depth, but may not extend as deep as the Round Lipped.
Behavior: They pretty much stay in one place and filter water through
themselves.
ID Clues: Look for a large Chimney like structure, they are quite distinctive in shape and appearance. If you want to get really high tech and tell the two species apart, look very closely and see if you can find the actual spicules - the Sharp Lipped species will have thorns protruding from some of the 4 rayed spicules.
Other Cool Facts: If you see one, look inside! YOY Rockfish, Grunt Sculpins and other cool critters often hide inside! Also, both are Siliceous Sponges, meaning that their spiculas are made of silica. Spicules are small structures present in many sponges that provide structural support. I just like saying the word Siliceous!!

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

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February 2011

Invasive Club Tunicate
Styela clava
Urochordata Phylum

Description: Leathery, bumpy bodies. Their siphons are smooth, with alternating dark/light bands around the edges. They have a thin stalk that attaches to a hard surface like a boat hull or a dock. Both siphons are erect.
Color: Tan to a rusty brownish colour
Range: Currently found in Washington and Canada in a few spots, as well as many other locations around the world. Native to Korea and Japan.
Size: up to about 5-6 inches
Hangouts/Habitat: Under docks and boats, usually hanging upside down
Munches on: Whatever it can filter out of the water
Depth: Very shallow, directly under the dock or boat.
Behaviour: Doesn't do much. Just hangs out.
Biggest Enemy: Well, see, that's the problem. Nothing eats it, so it can populate quickly and take over areas.
ID Clues: Look for the bumpy, warty body. Also check inside the siphons to see the light and dark bands. TAKE PHOTOS when you can!
Other Cool Facts: Much more about this invasive here, including photos of similar tunicates that might be mistaken for it.

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

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January 2011

Puget Sound Rockfish
Sebastes emphaeus
Scorpionfish Family

Description: One of the smaller rockfish and sometimes overlooked for other species.
Color: Orange to brownish colour
Range: Central California to Alaska
Size: up to 19 cm ( 7.5 inches)
Hangouts/Habitat: close to shores with rock and hangs out in (small) schools
Munches on: small fish and plankton
Depth: 10-30 meter (40-130ft) (average 17 meter- 57 feet)
Behaviour: usually hovering close to bottom.
Biggest Enemy: seals, sealions, other fish (in juvenile stage)
ID Clues: typical rock fish shape, very dark eye, dark blotch along the belly side, shallow notches between the spines of the dorsal fins, roundish anal fin
Other Cool Facts: We have seen them hanging in schools and following us as we moved along the reef. They are not as curious as some of the other rockfish but seemed to tolerate us at close range

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