Pisaster giganteus, the giant sea star, giant spined star, or knobby sea star is a species of sea star that lives along the western coast of North America from Southern California to British Columbia. It makes its home on rocky shores near the low tide mark. It preys on mollusks. It can grow as large as 24 in (61 cm) in diameter. Its color varies from brown to red or purple.
Giant sea stars have small eggs, and their sperm contain spherical heads. Once their larvae are born, they are bilaterally symmetrical. By the time they mature and reach adulthood they are centered on a set point with radial symmetry to their bodies. The gonads of the giant sea star grow in a winters time just in time for spawning season between the months of March and April.[1]
Habitatedit
Giant sea stars are usually found around the protected coastlines with low tide. They can often be found attached to rocks, pier supports or in the sand.[1]
Descriptionedit
Giant sea stars have a dense body with wide arms. Its surface is either tan or brown, but on occasion the giant sea star can have a yellowish or grayish surface. They contain thick, blunt spines that are bluish in color with white, pink or purple tips that are swollen and surrounded by brown fuzz and pedicellariae that have a plier like shape. These pedicellariae are used as a protective mechanism against predators.[1] They have no distinct pattern. They range from 36–48 cm (14–19 in) from the tip of one arm to the other. They are usually found up to 88 m (289 ft) down in the water.[2]
Predators and preyedit
The giant sea star only has a few predators. Sea otters and sea birds feed on giant sea stars, and their larvae are eaten by certain types of sea snails. They prey on several kinds of sea organisms including barnacles, gastropods, bivalves, and limpets. It eats its prey by extending its stomach so it can fit into tiny gaps, such as mussel shells.[3]
Sourcesedit
Aquarius Aquarium Institute: Giant Sea Star
Landenberger, Donald E. "Studies on Selective Feeding in the Pacific Starfish Pisaster in Southern California." Ecology, Vol. 49, No. 6 (Nov., 1968), pp. 1062-1075. Online. March 3, 2008.
Taxonomicon
Referencesedit
Wikimedia Commons has media related to Pisaster giganteus.
^ abc"Classification of Southern California Sea Stars". Retrieved 12 April 2012.
^McDonald, Gary. . Archived from the original on 6 August 2010. Retrieved 12 April 2012.
^"Pisaster Giganteus". SiMOn. Retrieved 12 April 2012.
May 05, 2024
pisaster, giganteus, giant, star, giant, spined, star, knobby, star, species, star, that, lives, along, western, coast, north, america, from, southern, california, british, columbia, makes, home, rocky, shores, near, tide, mark, preys, mollusks, grow, large, d. Pisaster giganteus the giant sea star giant spined star or knobby sea star is a species of sea star that lives along the western coast of North America from Southern California to British Columbia It makes its home on rocky shores near the low tide mark It preys on mollusks It can grow as large as 24 in 61 cm in diameter Its color varies from brown to red or purple Pisaster giganteus Scientific classification Domain Eukaryota Kingdom Animalia Phylum Echinodermata Class Asteroidea Order Forcipulatida Family Asteriidae Genus Pisaster Species P giganteus Binomial name Pisaster giganteusStimpson 1857 Contents 1 Reproduction and regeneration 2 Habitat 3 Description 4 Predators and prey 5 Sources 6 ReferencesReproduction and regeneration editGiant sea stars have small eggs and their sperm contain spherical heads Once their larvae are born they are bilaterally symmetrical By the time they mature and reach adulthood they are centered on a set point with radial symmetry to their bodies The gonads of the giant sea star grow in a winters time just in time for spawning season between the months of March and April 1 Habitat editGiant sea stars are usually found around the protected coastlines with low tide They can often be found attached to rocks pier supports or in the sand 1 Description editGiant sea stars have a dense body with wide arms Its surface is either tan or brown but on occasion the giant sea star can have a yellowish or grayish surface They contain thick blunt spines that are bluish in color with white pink or purple tips that are swollen and surrounded by brown fuzz and pedicellariae that have a plier like shape These pedicellariae are used as a protective mechanism against predators 1 They have no distinct pattern They range from 36 48 cm 14 19 in from the tip of one arm to the other They are usually found up to 88 m 289 ft down in the water 2 Predators and prey editThe giant sea star only has a few predators Sea otters and sea birds feed on giant sea stars and their larvae are eaten by certain types of sea snails They prey on several kinds of sea organisms including barnacles gastropods bivalves and limpets It eats its prey by extending its stomach so it can fit into tiny gaps such as mussel shells 3 Sources editAquarius Aquarium Institute Giant Sea Star Landenberger Donald E Studies on Selective Feeding in the Pacific Starfish Pisaster in Southern California Ecology Vol 49 No 6 Nov 1968 pp 1062 1075 Online March 3 2008 TaxonomiconReferences edit nbsp Wikimedia Commons has media related to Pisaster giganteus a b c Classification of Southern California Sea Stars Retrieved 12 April 2012 McDonald Gary Pisaster Giganteus Archived from the original on 6 August 2010 Retrieved 12 April 2012 Pisaster Giganteus SiMOn Retrieved 12 April 2012 Retrieved from https en wikipedia org w index php title Pisaster giganteus amp oldid 1187241268, wikipedia, wiki, book, books, library,
