Starfish die off in the NW Pacific

[RobertEarl]

2. Other starfish facts

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Diet of the starfish >> source wikipedia

Most species are generalist predators, eating microalgae, sponges, bivalves, snails and other small animals.[26][57] Some species are detritivores, eating decomposing organic material and faecal matter.[57][58] The crown-of-thorns starfish consumes coral polyps.[59] The processes of feeding and capture may be aided by special parts; Pisaster brevispinus, the short-spined pisaster from the West Coast of America, can use a set of specialized tube feet to dig itself deep into the soft substrate to extract prey (usually clams).[60] Grasping the shellfish, the starfish slowly pries open the prey's shell by wearing out its adductor muscle, and then inserts its everted stomach into the crack to digest the soft tissues. The gap between the valves need only be a fraction of a millimetre wide for the stomach to gain entry.[19]


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Ecological impact of starfish >>>> source whikipedia

Starfish devouring mussel
Pisaster ochraceus consuming a mussel in central California

Starfish are keystone species in their respective marine communities. Their relatively large sizes, diverse diets and ability to adapt to different environments makes them ecologically important.[61] The term "keystone species" was in fact first used by Robert Paine in 1966 to describe a starfish, Pisaster ochraceus.[62] When studying the low intertidal coasts of Washington state, Paine found that predation by P. ochraceus was a major factor in the diversity of species. Experimental removals of this top predator from a stretch of shoreline resulted in lower species diversity and the eventual domination of Mytilus mussels, which were able to outcompete other organisms for space and resources.[63] Similar results were found in a 1971 study of Stichaster australis on the intertidal coast of the South Island of New Zealand. S. australis was found to have removed most of a batch of transplanted mussels within two or three months of their placement, while in an area from which S. australis had been removed, the mussels increased in number dramatically, overwhelming the area and threatening biodiversity.[64]



Survival of ocean warming and ph change for mussels

A 2009 study found that P. ochraceus is unlikely to be affected by ocean acidification as severely as other marine animals with calcareous skeletons. In other groups, structures made of calcium carbonate are vulnerable to dissolution when the pH is lowered. Researchers found that when P. ochraceus were exposed to 21 °C (70 °F) and 770 ppm carbon dioxide (beyond rises expected in the next century), they were relatively unaffected. Their survivability is likely due to the nodular nature of their skeletons, which are able to compensate for a shortage of carbonate by growing more fleshy tissue.[81]



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Links and other sources

Lead Researcher: Fukushima pollution may be causing sea star epidemic on West Coast — Sea urchins, sea cucumbers also affected — “Something’s making them susceptible”… “It’s unlike anything we’ve seen”… “Populations go locally extinct overnight, literally”
http://enenews.com/lead-researcher-fukushima-pollution-a-cause-of-epidemic-wiping-out-starfish-along-west-coast-sea-urchins-and-sea-cucumbers-also-affected-something-is-making-them-susceptible-infection-it

Experts: Fukushima can’t be excluded as factor in sea stars turning to goo along West Coast; It hasn’t been ruled out — They’re “particularly proficient” at absorbing radioisotopes; 1,000 times more plutonium than fish
http://enenews.com/colonies-of-starfish-turning-to-mush-disintegrating-into-white-goo-experts-we-cant-exclude-fukushima-radiation-it-hasnt-been-ruled-out-starfish-particularly-proficient-at-absorbing-ra