Tag Archive: sea stars


TAXONOMY
Kingdom:  Animalia
Phylum:  Echinodermata
Class:  Asteroidea
Order:  Valvatida
Family:  Oreasteridae

Genus/species: Protoreaster nodosus

GENERAL CHARACTERISTICS: The backround body color is highly variable; may be beige, brown, orange, red or other hues, such as green or blue. Horn-shaped tall dark nodules are conical and arranged in a single row, radially on the dorsal (top) side. Most horned sea stars found are a roughly rigid five-pointed star-shape (occasionally 4 or 6) with tapering arms to the end.

Diameter up to 30 cm (12 in).

Protoreaster nodosus15010829781_2ff5562e7a_o

DISTRIBUTION/HABITAT: Red Sea, Indian and western Pacific oceans. Found in shallow sheltered sand and seagrass beds. Depth range 1 – 582 m (3.3 – 1900 feet).

seastar3289508350_970ef3292c_o 

DIET IN THE WILD: The mouth is located ventrally (bottom). The Chocolate Chip Seastar covers its food, then pushes out its stomach from inside its body of prey. Sea stars have a unique adaptation for consuming bi-valve mollusks (oysters, clams, mussels, etc.). Stars insert a portion of their stomach into the small “gape” between the valves of a mollusk. Stomach enzymes are released and digest the fleshy part of the mollusk inside its own shell. The digested contents are moved back into the sea star leaving an empty bi-valve shell. P. nodosus prefers sponges, corals, clams and snails, other invertebrates; also opportunistic carrion feeders.

 Protoreaster nodosus3289508974_49c4d004de_b

REPRODUCTION: P. nodosus is a broadcast spawner. As in other sea stars, fertilization is external. Eggs and sperm are stored in the rays and released simultaneously. Larvae look nothing like the adults. The form that first hatches from the eggs is bilaterally symmetrical and planktonic. Larvae eventually settle and transform into tiny sea stars.

Lifespan up to 17 years

sea star15201906310_bc5840e0c0_o 

PREDATORS: Triggerfish, pufferfish, boxfish and parrotfish.

CONSERVATION: IUCN Not Evaluated

REMARKS: The Chocolate Chip Seastars are also called “knobbly sea star” and the “horned sea star.”
The chocolate chip sea star can regenerate lost limbs, as long as the central disk of the body is intact. Some species can regenerate an entire body from an arm or arm segment.

References

California Academy of Sciences Steinhart Aquarium Mangrove Pop-Up, Main floor (level one) 2018

Ron’s WordPress shortlink wp.me/p1DZ4b-1ml

Ron’s flickr  https://www.flickr.com/photos/cas_docents/15010829781/in/set-72157608501343477/

Woods Hole www.whoi.edu/science/B/people/kamaral/SeaStar.html

Bishop Museum hbs.bishopmuseum.org/pubs-online/pdf/op11-8.pdf

Georgia Aquarium http://www.georgiaaquarium.org/animal-guide/georgia-aquarium/home/galleries/aquanaut-adventure/gallery-animals/chocolate-chip-sea-star

Reef Creature Identification, Humann and Deloach 2010, page 426

Encyclopedia of Life  eol.org/pages/4704956/details

Marine Biology http://link.springer.com/article/10.1007%2Fs00227-008-1064-2

 

TAXONOMY
Kingdom: Animalia
Phylum: Echinodermata
Class: Asteroidea
Order: Forcipulatida
Family: Asteriidae

Genus/species: Pisaster ochraceus

GENERAL CHARACTERISTICS: Color varies from orange, violet, dark brown or mottled, but very rarely ochre. One study showed that less than two percent of the individuals in three local Northern California populations were “ochre” in color. When dead and dry they become ochre in color.


The aboral surface contains many small spines (ossicles) that are arranged in a netlike or pentagonal pattern. Papulae or coelomic pouches give the seastar’s surface a soft, fuzzy appearance. They are used for respiration and waste excretion. P. ochraceus may have an arm radius of up to 28 cm (11 in), but the more common radius is half that figure. They typically have five arms or rays, but the number can range from four to seven. Like all sea stars, an adult P. ochraceus has tube feet which they use for locomotion and for handling prey.

DISTRIBUTION/HABITAT: Ochre stars range from Alaska to Santa Barbara County, California. They prefer the low-to-mid intertidal zones on rocky shores, especially on mussel beds, and are also found in the subtidal zone to a depth of 88 m (288 ft). Juveniles are found in crevices and under rocks.

DIET IN THE WILD: California mussels are the favored and locally abundant prey. They also consume acorn barnacles, emarginated dogwinkles, gooseneck barnacles, owl limpets, etc. They can insert their stomach into slits as narrow as 0.1 mm between the valves of bivalves and begin digestion.

ACADEMY DIET: Manila clams, chopped fish, large krill, chopped squid; it also eats other exhibit inhabitants.

REPRODUCTION: They are mainly dioecious (separate sexes). Male gametes are produced, but at a later date only females gametes are produced. During a transitional period, both eggs and sperm are produced. The gonopores of the individual gonads open at the bases of the arms. Fertilization is external. Larvae are free-swimming and plankton-feeding.

LIFESPAN: Up to 20 years

PREDATORS: Adults are eaten by sea otters and seagulls. According to Dr. Thomas Niesen, the sea otter can crunch them up but is also known to bite off the tips of the arms and suck out the gonads.

REMARKS:  One study showed that less than 2% of the individuals in three local Northern California populations were “ochre” in color. When dead and dry they become ochre in color.

P. ochraceus tolerate strong surges, large temperature changes, dilution by rainfall. It is resistant to desiccation and it can tolerate a loss of thirty-percent of its body weight in body fluids.

Sea stars can regenerate lost arms with a portion of the central disc intact and in some species from a single arm.

NOTE:   SEA STAR WASTING SYNDROME has become a major issue in both the Pacific and Atlantic Oceans since 2013. For an excellent summary check this link to the University of Santa Cruz 9-9-14.  http://www.eeb.ucsc.edu/pacificrockyintertidal/data-products/sea-star-wasting/updates.htm

Fitzgerald Marine Reserve. www.fitzgeraldreserve.org/newffmrsite/wp-content/uploads/...

11-17-14 Recent research identifies a virus (Parvoviridae) to be responsible for the wasting disease. Introduced virus was able to infect healthy sea stars with the virus, which then leads to the wasting symptoms. Published in the Proceedings of the National Academy of Science. http://theconversation.com/mystery-virus-that-turned-millions-of-starfish-into-goo-is-finally-identified-34336

 

Additional References

California Academy of Sciences Docent Tidepool Guide 2015

Woods Hole www.whoi.edu/science/B/people/kamaral/SeaStar.html

Bishop Museum hbs.bishopmuseum.org/pubs-online/pdf/op11-8.pdf

Encyclopedia of Life  eol.org/pages/598469/details

Animal Diversity Web, U of Michigan  animaldiversity.ummz.umich.edu/accounts/Pisaster_ochraceus/

Ron’s WordPress Shortlink  http://wp.me/p1DZ4b-sC

Ron’s flickr  https://www.flickr.com/photos/cas_docents/3407968572/in/set-72157608501343477/

 


TAXONOMY

Kingdom: Animalia
Phylum: Echinodermata
Class: Asteroidea (Starfish or sea stars)
Order: Forcipulatida
Family: Asteriidae

Genus/species: Asterina miniata

GENERAL CHARACTERISTICS: Colors may be colored red, orange, brown, purple or mottled. They have webbing between their short, triangular arms, which gives them a batlike look. Size is up to 20 cm (eight inches) across. Radially symmetrical they normally have five arms, but they occasionally have as many as nine arms. They have tube-feet that allow locomotion.

DISTRIBUTION/HABITAT: Sitka, Alaska to Baja California, Mexico. Found in low intertidal areas on rocks overgrown with surfgrass, large algae and sponges. Depth intertidal to 290 m (950 ft) on rocky or sandy substrates.

DIET IN THE WILD: Sensors at the end of each arm that sense light and detect prey. Typically an omnivore or scavenger: surfgrass, algae, colonial tunicates, organic films on hard surfaces, as well as other seastars.  Like most seastars, feeds by everting its stomach over prey.

See everted Bat Star stomach below.

REPRODUCTION: Usually spawns May to June. The male broadcasts sperm and the female broadcasts eggs from pores near the bases of their arms. Embryos and larvae are transparent.

PREDATORS Other sea stars, molluscs, and crustaceans. Like some other sea stars, bat stars can sometimes avoid predation by secreting chemicals that evoke flight responses in other animals.

CONSERVATION: IUCN No special status. Collecting by tidepool visitors has diminished some populations, for example around the Monterey Peninsula.

REMARKS: When two bat stars bump into each other, a gentle brawl begins. They seem to be “arm wrestling” in a slow motion skirmish where no winner is usually obvious.

Bat stars lack the pedicillariae, or pincers, common to most other sea stars and used to clear the animal of unwanted parasites and other debris. Even so, bat stars are free of debris, perhaps because small, constantly moving hairs (cilia) discourage settling

Sea stars have endoskeletons made up of plates (calcified ossicles) joined by connective tissue to protect the bat star’s vital organs.  The bat star’s ossicles are so large and defined that they look like rough shingles. 

 

REMARKS:  SEA STAR WASTING SYNDROME has become a major issue in both the Pacific and Atlantic Oceans. For an excellent summary check this link to the University of Santa Cruz 9-9-14.  http://www.eeb.ucsc.edu/pacificrockyintertidal/data-products/sea-star-wasting/updates.htm

Fitzgerald Marine Reserve.  http://www.fitzgeraldreserve.org/newffmrsite/wp-content/uploads/2014/09/BetweenTides_9-14_web.pdf

 

References

Monterey Bay Aquarium  http://www.montereybayaquarium.org/animal-guide/invertebrates/bat-star

U. of Michigan Animal Diversity Web http://animaldiversity.ummz.umich.edu/accounts/Patiria_miniata/

Ron’s flickr    http://www.flickr.com/photos/cas_docents/sets/72157608501343477/

Ron’s WordPress shortlink   http://wp.me/p1DZ4b-to

TAXONOMY
Kingdom: Animalia
Phylum: Echinodermata
Class Asteroidea
Order: Forcipulatida
Family: Asteriidae

Genus/species: Pisaster giganteus

 GENERAL CHARACTERISTICS: Giant sea stars have five arms covered with white, pink, or purple spines surrounded by blue tissue at the base, and range in color from red, orange, brown, or even green. The surface has brown fuzz and pedicellariae. They have a maximum arm span of about 60 cm (23.6 in). P. giganteus would seem improperly named, as the average intertidal specimen is smaller than the average P. ochraceous; however subtidal specimens grow considerably larger.

7137830837_192c64b940_k 

DISTRIBUTION/HABITAT: They are distributed along the eastern Pacific coast from British Columbia to Baja California. They are common on rocky substrates, but also found on sand from the middle to lower intertidal zone down to 90 m (300 ft).

Giant Sea StarIMG_1040.JPG - Version 2

DIET IN THE WILD: Their typical prey are hard-shelled organisms such as mussels, snails, and barnacles by extending its stomach to fit into tiny gaps in bivalves such as mussels. However, they may occasionally eat anything slow-moving enough to be caught, such as a dying fish or shellfish, anemones, or other sea stars.

Giant Seastar IMG_8851

PREDATORS: Sea gulls and sea otters are sea star predators.

REPRODUCTION: Individual sea stars are male or female. Both sexes release gametes into the water for external fertilization. Larvae are planktonic and have bilateral symmetry. Giant sea stars live about 20 years.

REMARKS:  SEA STAR WASTING SYNDROME has become a major issue in both the Pacific and Atlantic Oceans. For an excellent summary check this link to the University of Santa Cruz 9-9-14.  http://www.eeb.ucsc.edu/pacificrockyintertidal/data-products/sea-star-wasting/updates.htm

Fitzgerald Marine Reserve.  http://www.fitzgeraldreserve.org/newffmrsite/wp-content/uploads/2014/09/BetweenTides_9-14_web.pdf

Tidepool 

References

California Academy of Sciences Tidepool Exhibit 2015

Woods Hole www.whoi.edu/science/B/people/kamaral/SeaStar.html

Bishop Museum hbs.bishopmuseum.org/pubs-online/pdf/op11-8.pdf

Encyclopedia of Life  eol.org/pages/598468/details

Animal Diversity Web, ADW  http://animaldiversity.ummz.umich.edu/accounts/Pisaster_giganteus/classification/

Ron’s flickr  https://www.flickr.com/photos/cas_docents/7137830837/in/set-72157608501343477

Ron’s WordPress shortlink  http://wp.me/p1DZ4b-1mV

TAXONOMY
Kingdom: Animalia
Phylum: Echinodermata
Class Asteroidea
Order: Forcipulatida
Family: Asteriidae

Genus/species: Pisaster brevispinus


GENERAL CHARACTERISTICS The pink sea star reaches a maximum diameter of nearly 65 cm (2 ft); however, individuals are usually smaller. Its central disc has a raised, humplike appearance. They are robust, pink in color and have aboral spines much shorter than those of other Pisaster species, thus its scientific name, which translates as “short-spined sea star.”

7137858011_f41cdc4304_k

DISTRIBUTION/HABITAT They range from Sitka, Alaska to San Diego County, California. They can occasional be seen in the low intertidal zone, but are more commonly found in deeper water to 90 m (300 ft ) on sand and mud substrates, but sometimes on rocks and pier pilings in calm waters. They cannot tolerate prolonged exposure to air.

DIET IN THE WILD: Pink sea stars prey on live clams, snails, sand dollars, barnacles, mussels, – annelid worms, and scavenge on dead fish and squid. On soft surfaces, P. brevispinus digs into sand or mud with its arms. It also can extend its tube feet (the ones around its disk) to a length of 20 cm (8 in). When the tube feet reach a clam buried in the mud, they attach and the sea star hauls it up. On shale, it can lower its stomach into the burrow of a clam and digest the animal in place. Their large size may well be due to their access to a plentiful food supply of large organisms unavailable to potential competitors.

PREDATORS Large adults have few predators, but they may be taken by the sunflower sea star Pycnopodia helianthoides. Sea otters have been known to detach rays to consume gonads, and sea gulls occasionally feed on individuals exposed during very low tides.

REPRODUCTION They spawn in the spring. Sexes are separate and fertilization takes place externally. Larvae disperse in the water column.

Pink stars can live up to 20 years.



REMARKS: Can chemosense clams through sand. May dig down to the clam for 2 –3 days or extend tube feet to the clam a distance equal to the arm radius to 20 cm (7.8 in). Once contacted,
the clam is lifted from the substrate or the stomach may be everted to 8 cm (3.15 in) to digest the prey in place. Some sand-bottom invertebrates including the sand dollar Dendraster excentricus and the snail Olivella biplicata chemosense the presence of a pink star and attempt to avoid contact by burrowing.

References

California Academy of Sciences Tidepool exhibit 2015

Walla Walla Univ. www.wallawalla.edu/academics/departments/biology/rosario/…

EOL eol.org/pages/598470/details

Ron’s WORDPRESS SHORTLINK  http://wp.me/p1DZ4b-tA

Ron’s flickr http://www.flickr.com/photos/cas_docents/sets/72157608501343477/

TAXONOMY
Kingdom: Animalia – animals
Phylum: Echinodermata Klein – echinoderms
Subphylum: Eleutherozoa
Superclass: Cryptosyringida
Class: Ophiuroidea – basket stars, brittlestars, snake stars
Order: Ophiurida – basket stars, serpent stars, basket stars, serpent stars
Suborder: Iohiura incrassata
Family Ophiodermatidae

Genus/species: Ophiarachna incrassata

GENERAL CHARACTERISTICS: Green with yellow markings and dark-ringed white spots. Disc diameter to 5 cm (2 inches) and arm length to 20 cm (8 inches). Top of arms are wide and flat.

Stout Green Brittle Star8412648309_4004cdfca2_k

DIET IN THE WILD: Nocturnal feeder of  small organisms and detritus.

Stout Green Brittle Star4472769084_f4acdf93f2_o

DIET IN THE WILD: Small organisms and detritus. Nocturnal feeder.

Stout Green Brittle Star8282559749_1cb63a02d1_oReferences

Ron’s flickr  https://www.flickr.com/photos/cas_docents/8412648309/in/set-72157608501343477/

Encyclopedia of life  eol.org/pages/598310/details

Reef Creature Identification, Humann and Deloach 2010, page443

ADW animaldiversity.ummz.umich.edu/accounts/Ophiarachna_incra…

Ron’s WordPress shortlink  http://wp.me/p1DZ4b-1mb

 

TAXONOMY
Kingdom: Animalia
Phylum: Echinodermata
Class: Ophiuroidea – basket stars, brittlestars, snake stars
Order: Ophiurida – basket stars, serpent stars, basket stars, serpent stars
Family: Ophiodermatidae

Genus/species: Ophiothrix spiculata

 

GENERAL CHARACTERISTICS: Color highly variable: green, green-brown, or green-yellow, and more or less extensively marked with white, grey, orange, red, brown, or pink. Distinguished by serrate or conspicuously prickly spines on the disk and arms. Up to eight serrated and hyaline arm spines with jagged edges, radial symmetry with 5 segments. Disk up to 18mm (0.7 inches) in diameter, arms up to 85 mm (3.3 inches) in length.

DISTRIBUTION/HABITAT: Northern California to Peru; also Galapagos Islands. Found on the continental slope, kelp forest, submarine canyons. sandy and rocky seafloor in shallow waters to great depths from the shoreline down to 2,059 m (6,755 feet).

DIET IN THE WILD: They extend their arms are upward to filter the water for organic particles, small animals. They are nocturnal stretching out to catch food particles, using their small spines to pass the bits down to the central mouth.

PREDATION: When threatened their best form of defense is to slowly crawl away.

 

 

REMARKS: In kelp forests near La Jolla in southern California, millions of them may carpet the seafloor in layers up to an inch thick!

The arms of the spiny brittle star are very delicate and easily break off when the animal is disturbed. These echinoderms are able to replace lost arms in several days.

They are sensitive to light, and when disturbed can create their own light or bioluminescence.

References

Encyclopedia of Life eol.org/pages/598202/details

Monterey Bay Aquariun  http://www.montereybayaquarium.org/animal-guide/invertebrates/spiny-brittle-star

NOAA   http://www8.nos.noaa.gov/onms/park/Parks/SpeciesCard.aspx?pID=3&refID=4&CreatureID=151 

Ron’s flickr  http://www.flickr.com/photos/cas_docents/sets/72157608501343477/

Ron’s WordPress shortlink  http://wp.me/p1DZ4b-gs

TAXONOMY
Kingdom: Animalia
Phylum: Echinodermata
Class: Asteroidea
Order: Valvatida
Family: Goniasteridae

Genus/species: Mediaster aequalis

Vermillion Sea StarIMG_3431

GENERAL CHARACTERISTICS: 5-rayed sea star has conspicuous marginal plates. Orange to vermillion red. Aboral surface covered with oval or flat-topped hexagonal plates (ossicles). Oral side lighter. Up to 20 cm ( 7.9 inches) diameter.

 Vermillion Sea StarIMG_5328

DISTRIBUTION/HABITAT: Alaska south to southern California. Common in subtidal waters; rarely exposed to the air. Found especially in rocky areas; occasionally on sand and gravel. Depth to 1,784 m (5,800 feet) max.

DIET IN THE WILD: Omnivorous: sponges, bryozoans, tunicates, algae, and detritus. Also known to feed on sea pens.

Vermillion Sea Star6182821598_7b9c9777d0_o

PREDATOR: Seastar Solaster dawsoni.

REMARKS: Moves more rapidly than most sea stars: up to 40 cm (16 inches) minute.

References

Encyclopedia of Life eol.org/pages/598026/details

Walla Walla University http://www.wallawalla.edu/academics/departments/biology/rosario/inverts/Echinodermata/Class%20Asteroidea/Mediaster_aequalis.html

Ron’s flickr  https://www.flickr.com/photos/cas_docents/3051541919/in/set-72157608501343477/

Ron’s WordPress shortlink  http://wp.me/p1DZ4b-1lP

Family Poraniidae 

Dermasterias imbricate

DISTRIBUTION: Eastern North Pacific: Alaska to Northern California. 

HABITAT: On rocks and rocky reefs in subtidal areas.  APPEARANCE: Medium size sea star up to 5 Iin or 12 cm in diameter with disproportionately short broad arms with a smooth, slippery surface. Mottled coloring—bluish-grey with brown to orange blotches all over.  Oral side pale and smooth. Smells garlic-like.  

DIET: Mainly sea anemones, but also takes sea cucumbers, sea urchins, and other invertebrates. Leather stars, unlike many other sea stars, such as the ochre, bat, and pink sea stars, swallow their prey whole and digest internally. 

REPRODUCTION/DEVELOPMENT: Releases eggs and sperm; fertilized eggs float in plankton and develop into juveniles, which eventually settle out.

REMARKS: Known to eat the Plumose Anemone (Metridium senile and Metridium farcimen), and the Strawberry Anemone Corynactis californica.

Larger anemones have been observed to fight back by distending the mouth to envelope the attacking star. In the end the leather star often retreats and both the star and the anemone are none the worse for wear. 

 

LOCATION: Tidepool  CC15    **DisplayIntermittent 

WORDPRESS SHORTLINK   http://wp.me/p1DZ4b-u0

flickr    http://www.flickr.com/photos/cas_docents/sets/72157608501343477/

Phylum Echinodermata, Class Asteroidea, Order Forcipulatida, Family Asteriidae, 

Pisaster gianteus

 

DISTRIBUTION: Eastern Pacific coast from British Columbia to Baja California.

HABITAT: Rocky but also sandy substrates from middle to lower intertidal zone down to 300 ft or 90 m.

APPEARANCE: Five arms. Can be colored red, orange, brown, or green. Evenly spaced blunt white stubby spines surrounded by blue plaques.  Maximum arm span about 24 in or 60 cm.

DIET: Typical prey are hard-shelled organisms such as mussels, snails, and barnacles. May occasionally eat anything slow-moving enough to be caught, such as dying fish or shellfish, anenomes, or other sea stars.

REPRODUCTION and DEVELOPMENT: Individual sea stars are male or female. Broadcast spawners, both sexes release gametes into the water for external fertilization. Larvae are planktonic and have bilateral symmetry.

MORTALITY/LONGEVITY: Sea gulls and sea otters are sea star predators. Giant sea stars live about 20 years.

TIDEPOOL CC15  

WORDPRESS SHORTLINK  http://wp.me/p1DZ4b-tO

flickr  http://www.flickr.com/photos/cas_docents/sets/72157608501343477/

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