Organism List at Coal Oil Point




Spotted Unicorn - Acanthina punctulata


Angular Unicorn - Acanthina spiratta


Variegated Amphissa - Amphissa versicolor


California Cone - Conus californicus


Norris's Top Snail - Norrisia norrisi


Purple Olive - Olivella biplaculata


Poulson's Rock Snail - Roperia poulsoni


Kellet's Whelk - Kelletia kelletii


Chestnut Cowrie - Zonaria spadicea (formerly Cypraea  spadicaea)

It is chestnut colored in the middle with white to gray edges.  Mantle is rosy brown with black speckles.  About 2 5/8" long.  Found under ledges and in crevices of lower intertidal zone.


Tinted Wentletrap - Nitidiscala tincta (formerly Epitonium tinctum)

White shell with brown or purple stripe in the suture.  About 5/8" long.  Among rocks or in tidepools of low intertidal zone.


White Bubble Snail - Haminoea vesicula

It is translucent to whitish or greenish shell, with a sunken spire.  Strongly curving internal profile with flaring anterior lip.  Usually less than 15 mm long.  Found in mud flats, intertidally.


Scaly Tube Snail - Serpulorbis squamigerus

Partially coiled tube, no operculum, length about 5 inches, diameter about 0.5 inches; Calcium carbonate tube.  The tube has a twisted shape with longitudinal ribs.  The surface is wrinkled and covered in scales.  Found from Gualla, Sonoma County, CA to Baja California.  Attached to rocks throughout the intertidal to about 100 feet  (30 m).


Shield Limpet - Lottia pelta (formerly Collisella pelta)

Brown with a variety of markings and a wavy edge.  Apex is high.  2 1/8" long, 5/8" high.  On rocks and in mussel beds from high to low intertidal zone.


Black Limpet - Lottia asmi (formerly Collisella asmi)

Black with radiating ridges and high profile.  Approximately 1" long.  Found on rocks and in tidepools of mid-intertidal zone.


Ribbed Limpet - Lottia digitalis (formerly Collisella digitalis)

Gray with greenish-brown bands and a wavy margin.  About 1" long. Found in rocky areas and splash zone of high intertidal zone.


Unstable Limpet - Lottia instabilis (formerly Collisella instabilis)

Brown exterior with white interior, it is saddle-shaped when turned on its edge.  1 3/8" long.  Found on the stems of various species of kelp, in the low intertidal zone to subtidal (240').


Surfgrass Limpet - Notoacmea paleacea

The shell is wide with parallel sides and a notch in the anterior right margin.  Exterior is light brown with dark margins; the interior is white with a bluish hue.  Shell is 10 mm long, 3 mm wide.  Common on leaves of surfgrass in low intertidal zone.


Owl Limpet - Lottia gigantea

Up to 3" long, large dark brownish grey limpet with some white. Leave scars on rocks.  The limpet has a low profile with the apex very near to the front.  Found in the high to mid intertidal zone on rocks on rocky shores.  Washington to Baja California.


Volcano Limpet - Fissurella volcano

Up to 1" long, conical ashy-pink shell with sharp reddish or reddish-brown rays, hole at apex. Animal bright yellow coloured w/ red stripes or brown shell w/ four white rays.  High to mid intertidal zone rocks on rocky shore.


Sea Hare - Aplysia sp.  (Aplysia californica and Aplysia vaccaria most common)

Dark brownish-green or olive green with wing-like flaps over back, usually with darker blotches.  Low tidal zone, rocky shores, and mud flats


California Mussel - Mytilus californicus

Up to 5" long, front margin straight, back margin curved; few but prominent ribs; purplish-black colour, but young are streaky brown and white; rounded ridges extend the length of each shell.  High to Low intertidal zone on rocks; Alaska to Baja Califormia


Platform mussel - Septifer bifurcatus

Up to 2", dark purple, with shell covered with prominent looking ribs with branching, somewhat harry.  Low intertidal zone, under rocks or rocky shores.  Monterey, CA, to Cabo San Lucas, Baja California


Date Mussel - Lithophaga plumula

Rounded anterior end and tapered posterior end.   The posterodorsal slope is ridged, feathery, or chalky incrustation with transverse wrinkling.  Interior is metallic gray.  About 55 mm long.  Bores into shale and mollusk shells in the low intertidal zone.


Chama clam - various species (Chama arcana most common)

Up to 1" high, 2" wide, shells translucent to dirty white, usually a rough shell.  The Chama arcana is an opaque to translucent white tinged with pink or orange, with its beak coiled to the right.  Low intertidal zone, rocky shores.


Flat-tip PiddockPenitella penita

Elongately ovate with an inflated anterior and flattened posterior separated by an elongated groove.  Exterior is white with a brown periostracum and fine, crowded ridges.  Interior is white.  Length is 1.25 – 3 in.  Found in clay and soft rock from low intertidal to water 72' deep.  Alaska to central Baja California.


Two-Spot Octopus - Octopus bimaculoides

The octopus has two eyespots, one below each eye. Cirri is abundant on the skin, arms four to five times bigger than the body, colour varies.  24" length; the eyespots are bluish-black.  Santa Barbara, CA to Cabo San Lucas, Baja California and Sea of Cortex, in crevices and caves, low intertidal to 165 ft.


Opalescent Nudibranch - Hermissenda crassicornis

Has a yellow-green body with orange areas on the back and a blue line on the sides.  The cerata have white tips.  Normally 1.5" long, but can grow up to 3" long.  Found on mud flats, eelgrass beds, docks and rocky intertidal areas.  Alaska to Mexico.


Black-and-White Dorid - Acanthodoris rhodoceras

White to grey-white on dorsum, with black tips of tubercles along body margin and yellow outside the black line.  The gills are rust-brown to black.  About 12-25 mm long.  Common in rock pools and mud flats in the low intertidal zone.


Red Abalone - Haliotis rufescens

Outer shell is usually brick red, occasionally with bands of green or white. Three or four of holes in shell remain open. Length 12.3"; 3-4 holes have raised edges.  Sunset Bay, Oregon to Bahia Tortugas, Baja California on rocks occasionally moves across sand of gravel bottoms; their habitat is low intertidal in rock crevices with heavy surf.


Pink Abalone - Haliotis corrugata

Rounded shell with scalloped margin.  Greenish to reddish brown in color with irregular diagonal rows of nodes, and black tentacles.  The shell holes have raised rims.  Interior is iridescent pink or green.  Usually 15 - 17 cm long.  Common on exposed rock surfaces in the low intertidal zone.



Nutall Chiton - Nutallina californica

Up to 1.5" long, very rough, spiny girdle, dull brown coloured streaked w/ white; the girdle has primarily short, brown bristles; the valves are black with an occassional white stripe down the dorsal ridge.  Mid intertidal zone, on rocks, often in furrows, rocky shores


Mossy Chiton - Mopalia mucsosa

Up to 2" long, round in shape, brownish colored and covered with stiff stout short hair.  Found in the low intertidal zone, on rocky shores, under rock and on rocks; Alaska to Baja California.





Purple Sea Urchin - Strongylocentrotus purpuratus

Short purple spines, can have 3.5 inch diameter but juveniles are less than 1-inch and have spines that are greenish.  Cook's Inlet, Alaska to Isle Cedros, Baja California. On rocks from low intertidal to about 10 meters.


Southern 2- Coloured Starfish (Giant Spined Star) - Pisaster giganteus

4-8" wide, bright purple slaty spines appear against yellow-orange background; a blue ring surrounds every white tipped spine.  Low intertidal zone, rocky shores especially at a surf; Vancouver Island, BC, to Baja California.









Opaleye - Girella nigricans

15" long, with fish more than 4" long living below low-tide zone.  It is dark grey with a single white spot on each side of the back.  High to mid tidal zone, abundant in rocky shore tidepools.


Tidepool Sculpin - Oligocottus maculosus

Color is brown to green or red on dorsal side, color fades on underside.  About 3.5 " long.  Found in tidepools in nearly any intertidal zone.


Plainfin MidshipmanPorichthys notatus

Also known as the “Singing Toadfish” due to the croaking sound it makes during mating season.  Has a double row of white photophores on its belly.  Grows to about 15” long.  Low intertidal zones under rocks.


Monkeyface Prickleback - Cebidichthys violaceus

Has a rounded head with a lumpy ridge.  There are two dark bands that radiate back from the eyes.  Has a  lateral line just below the dorsal fin.  Coloration is a dark olive to black.  Length is 76 cm.  Found in rocky coastal zones and tidepools from Oregon to Baja California.


Striped KelpfishGibbonsia metzi

Green in color with a variety of striped patterns.  Dorsal soft rays evenly spaced.  Low intertidal amongst Phyllospadix.  Vancouver Island, BC, to Baja California.


Crevice Kelpfish  Gibbonsia montereyensis

Usually “kelp” colored to very mottled.  Dorsal soft rays are unevenly spaced.  Low intertidal from Vancouver Island, BC, to Baja California.


Giant KelpfishHeterostichous rostratus

Greenish-yellow to reddish-brown with silvery stripes.  Body is slender and long.  The snout is long and the tip of the lower jaw extends beyond the upper jaw.  The caudal fin is forked.  Up to 2’ long.  Located in rocky areas with eelgrass and leafy red algae.  British Columbia to Baja California.


CabezonScorpaenichthys marmoratus

Marble coloration but actual color varies.  Has protruding flaps over the eyes and nostrils.  Poisonous spines of fin rays.  Found intertidally on hard bottoms in rock, gravel, or sand.  Alaska to Baja California.


Grass RockFish - Sebastes rastrelliger

            Dark olive green with lighter coloration ventrally and dark fins.  Its peritoneum is light and it is convex between the eyes.  Approximately 17 - 25 short gill rakers on first gill arch, 8 head spines, and a deep, thick caudal peduncle.  Maximum length is 22".  Located Oregon to Baja California.


Mussel Blenny - Hypsoblennius jenkinsi

            Grows to about 4.4" and has rayed fins.  The species matures around two years of age.  Its habit is subtidal to 21 m , and is found in crevices and burrows.  Located from Puerto Marquis, Mexico, including the Gulf of California, to Coal Oil Point, Santa Barbara County.








Mucus SpongePlocamia karykina

It has scarlet to salmon-orange coloration.  Have large oscula (pores) that are sparse and irregularly spaced.  Has double-headed spicules.  Approximately 10” wide and 1” thick.  Mid to low intertidal from Vancouver, BC, to Baja California.





Aggregation Anenome - Anthopleura elegantissima

Up to 3" wide, often covered with sand or gravel, circular, forms large squishy camouflaged colonies on rocks; have pale green tentacles with pink or purple tips and a pale green to gray column.  High to mid intertidal zone, rocky shores


Brown Annulated Hydroid - Eudendrium californica

Grows in a bushy colony with short branches and an erect stem.  Exoskeleton on the stem and branches is stiff and brown.  The feeding polyps are large and pink with white tentacles.  15 cm in height and 16 - 20 tentacles.  On rocks and under ledges so as to be protected from heavy wave action, rocky shores in low intertidal zone.



Worms (Annelida)


Oval FlatwormPseudoalloioplana californica  (formerly Alloioplana californica)

Oval body with green to brown zigzag patches radiating to the outer edges.  Eyespots cover the retractable tentacles.  Up to 1.5” long and 0.75" wide.  Found in the mid intertidal zone in crevices, on rocks, or resting on sand.  California to Baja California.


Tapered FlatwormNotocomplana acticola   (formerly Notoplana acticola)

Tan with darker center patches on dorsal side.  The rear tapers to a point.  Up to 6 cm long and 1.9 cm wide.  Under rocks from high to low intertidal zones along the entire California coast.


Sand-Castle Worm - Phragmatopoma californica

Cream colored worms with lavender tentacles and black bristles.  It is a tube builder and is found in colonies that form a honey comb design.  Grows up to 2" long.  Located on rocky shores with sand from the low intertidal zone to deep water.  Central California to Baja California.


Calcareous Tube Worms - Dodecaceria sp.

Forms colonies of calcareous tubes.  Dark brown to black in color with rounded heads.  Mature worms are about 40 mm long.  Reside in middle intertidal zone protected by rocky shores and dock pilings.  Subtidal to about 20 m.


Peanut WormsPhascolosoma sp.

The anterior section of the body is paler green with black lines and blotches; the posterior section of the body is pale green.  Bilaterally symmetrical and unsegmented.  Tentacles surround the mouth.  Length is about 6 – 7 cm.  Found under rocks or in crevices in the intertidal.







Sipunculid - Themiste zostericola

Long cylindrical body with dark gray lines.  Have small club-shaped papillae and pale yellow, brown, red or dark purple, highly branched tentacles.  Length averages 15 cm.  Common in low intertidal sand and under rocks.





Goose Barnacle -  Pollicipes polymerus

Up to 4" high, chalky white plates surmount black and wrinkled neck.  High to low intertidal zone, rocky shores and caves, pilings in bay


Acorn Barnacle - Balanus glandula

White to gray, cone-shaped.  Younger specimens have a visible black lining of the cover plates.  Up to 3/4" in diameter and 3/8" in height. Found on rocks in high to mid-intertidal zone and on various hard-shelled animals.  Aleutian Islands to Southern California.


Little Brown Barnacle - Chthamalus dalli

Has a grayish brown shell with a relatively large central opening.  There is a "+" pattern where the cover plates meet.  Grows up to 1/4" in diameter and 1/8" high.  Attached to rocks in the high intertidal zone.  Alaska to San Diego, CA.


Red Thatched Barnacle - Tetraclita  rubescens

Adults are brick red and volcano shaped.  The exterior is thatched with a small opening. Size is about 2" in diameter and 2" high.  On rocks in exposed sites in mid to low intertidal zone. 


Speckled Pillbug - Cirolana harfordi (Also called the Dark-Backed Rock Louse and Scavenging Isopod))

About 3/4" long, yellow or grey with dark blotch down middle of back; it has a distinct triangular tailpiece.  High intertidal zone, under rocks in tide pools; British Columbia to Baja California


Beach Isopod - Alloniscus perconvexus

Cream, brown, or gray in color with white patches.  Has the ability to roll into a ball.  Has pairs of antenna, a three-jointed flagellum, five pairs of pleopods, and hornlike tubercles on the head.  About 16 mm long.  Burrow in damp sand, seaweed and debris above the high tide mark.


Spot-Bellied Rock Crab - Cancer antennarius

Orange-brown carapace with red spotted on the underside.  The large claws have black tips. Carapace up to 7" wide.  Rocky shores from the low intertidal zone to deep water.  Queen Charlotte Sound, BC, to Cabo San Lucas, Mexico.


Porcelain Crab - Petrolisthes cinctipes

1.5" wide, small flat, greenish brown with brilliant red and blue marks on claws; it has red mouthparts and red spots at the base of the moveable part of each claw.  Lower middle zone under rocks and rock shelters like mussel shells; British Columbia to Baja California


Striped Shore Crab - Pachygrapsus crassipes  

Up to 2.5" wide. Dark green, usually with reddish and wavy light markings or stripes squat flat body; black stripes across the front of the body.  High to mid intertidal zone, rocky shores, tidepools; Oregon to the Gulf of California


Shield-Backed Kelp Crab - Pugettia producta

Olive in color with varying amounts of red and yellow.  Shield-shaped carapace.  Carapace up to 3.5" wide.  Live in or on seaweed, from intertidal zone to water as deep as 240'.


Beach Ghost Shrimp - Callianassa affinis

Elongated, white body with one claw much larger.  Usually about 2.5" long.  Live in permanent burrows in sandy gravel or beneath rocks in the mid-intertidal zone.


Sitka Shrimp - Heptacarpus sitchensis (formerly Heptacarpus pictus)

Normally greens with red diagonal stripes and blue dots.  Has a stout body with an elongated rostrum.  About 1" long.  Found in gravel areas, beneath rock at low tide, in mid-intertidal zone.  Alaska to Baja California.


Betaeus harrimani

Convex carapace, terminal joint of walking legs is slender, and it is transparent except where pigmented.  Length is about 30 mm.  Found under rocks, logs, and debris on protected shores of low intertidal zone.


Hairy Hermit - Pagurus hirsutiusculus

Narrow white band on lower portion of each walking leg, sometimes with a blue spot. Brownish antennae bear distinct banding.  Much of the crab is covered in hair.  Grows up to 3/4" long.  Found in tidepools in mid-intertidal zone to water as deep as 363'.



Intertidal Plants


Sea Lettuce  (Tube weed) - Ulva sp. (also known as Enteromorpha sp.)

Up to 5" long, mostly green with smooth-edged sheets.  The cell layers are thick, sheet-like or leaf-like and are several square feet in area; elongated, unbranched, hollow blades.  High to mid intertidal zone, bay flats, rocky shores


Turkish Towel Red Algae - Gigartina sp.  (G. leptorhynchos, G. caniculata, and G. spinosa most common)

Multitude of papillae covering surfaces of the blades, dark red to black, male plants lack papillae may resemble Rhodoglossum.  High to mid intertidal zone and shallow subtidal zone, northern and southern most abundant


Nori or Laver - Porphyra sp.  (Porphyra perforata most common)

Very thin, membranous blades, some with ruffled, stipeless blades, greenish-purple some with tapering blades.  High intertidal zone on rocks or shells; Alaska to Mexico


Articulated Coralline Algae - Corallina sp.

Pinnate branching more or less distichous, minute uncalcified pads between stony segments.  Aleutian Islands to Galapagos Islands, mid to lower intertidal zones


Feather Boa Kelp/Venus's Girdle - Egregia sp.  (Egregia menziesii most common)

Up to 17' tall, light yellowish-brown, several long stipes from massive holdfast, blades with frilly edge and air bladders look like olives.  Low intertidal zone, deep water, often cast on shore




Surf GrassPhyllospadix torreyi

Approximately 5’ long and 1/8” wide.  It has long, waxy blades with an oval to round cross-section.  Low to upper intertidal on exposed areas of rock.  Ranges from Alaska to Mexico.


Giant Bladder ChainCystoseira osmundacea

Color varies from tan to dark brown.  The lower branches are fern-like while the upper branches are rounded with small bladders forming continuous chains.  Grows up to 26’ tall.  Found in the low intertidal zone from Oregon to Baja California.


Giant Perennial KelpMacrocystis pyrifera

Brown blades, tall and pyramid shaped.  Can reach 150’ long.  Located in the low intertidal zone to deep water.  Its habitat is coarse sand or rocks.  Ranges from Alaska to Baja California.


Rubber ThreadsNemalion helminthoides

It is golden brown to reddish brown in color.  The plant body is generally unbranched.  8 – 18” tall and 1 – 4 mm in diameter.  On sheltered rocks in high to mid-intertidal zone.  Aleution Islands to Baja California.


Succulent SeaweedSarcodiotheca gaudichaudii (formerly Neogardhiella sp.)

Color ranges from pink to red.  Has slender, fleshy branches.  Size approaches 16” long.  Found in rocky areas of the low intertidal to subtidal water, and occassionally in tide pools.  Grows from Alaska to Chile.


Leather TubeScytosiphon lomentaria

Tubular thalli are about 2 – 6” long.  Found in clusters, common with crustlike attachments.  Small plants are slender and straight, while large plants are irregularly constricted.  Small plants more common in high tidepools and large plants are more common in low intertidal zone.


Like a PeacockTaonia lennebackerae

Fan-shaped with thin, brown blades.  When the plant is mature the tips are often split and lacerated which gives a linear look.  Ranges from sandy, low intertidal pools and rocks to low subtidal zone.


Beautiful LeafCallophyllis sp.

Rose to orange-red in color.  Flat with thin blades and somewhat fan-shaped.  Usually less than 4” tall.  Most common in deep waters, but found intetidally as driftweed.


Centroceras clavulatum

Have whorls of spines as each node where the plant fragments.  Found on rocks in sand-swept low intertidal zones from Santa Cruz to the Mexican border.


Red BladderErythrocytis saccata

Small, reddish-purple plant that grows from the apical pit of some of the branches (several plants may arise from one pit).  0.2 – 1.2” in height.  Monterey to Mexican border.


Belly BranchGastroclonium coulteri

Consist of mainly cylindrical, fleshy, branched stipe parts, with a few hollow, swollen chambers.  Up to 10” long.  Found in pools or on the sides of rocks (not fully exposed) in the low intertidal zone.


Very SlenderGracilaria sp.

They are usually cylindrical and deep red to brownish-red in color.  G. textorii var. cumminghamii has dichotomous branching, whereas G. sjoestedtii and G. verrucosa are spaghetti-like plants.  G. sjoestedtii grows up to 6.5’ tall and G. verrucosa is generally less than 6” tall.  G. textorii var. cunninghamii grows in tide pools to subtidal zone.  G. sjoestedtii is found in mid intertidal to shallow subtidal zone, and G. verrucosa is found in quiet water.


Laurencia pacifica

Bushy, dark purple plants with short, stubbly branchlets.  Several centimeters tall.  Commonly found with Erythrocystis.  Identifiable by an acrid smell.  Abundant throughout intertidal zone.


Sea Laurel - Laurencia spectabilis

A pinnate, flattened species.  Its blades resemble that of a sea rocket.  It is identifiable by an acrid smell.  Found throughout entire California coast.


Tiffeniella snyderiae

Reddish-pink tufts or patches.  The filaments are single rows or elongated cells.  Typically less than 2” long.  Found with surf grass in shaded tide pools or mats of intertidal algae.


Ectocarpus sp.

Light brown, hair-like algae.  Usually seen as hairy growth on other algae.  Found in tidepools at high intertidal zone.


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