Starfish have been disappearing along Canada's west coast. In those still found, their tissues are disintegrating and scientists don't know what might be killing them.
Marine biologist encountered this phenomenon and wrote to a colleague:
“[The starfish] seem to waste away, ‘deflate’ a little, and then just … disintegrate.
The arms just detach, and the central disc falls apart. It seems to happen rapidly, and not just dead animals undergoing decomposition, as I observed single arms clinging to the rock faces, tube feet still moving, with the skin split, gills flapping in the current.
The arms just detach, and the central disc falls apart. It seems to happen rapidly, and not just dead animals undergoing decomposition, as I observed single arms clinging to the rock faces, tube feet still moving, with the skin split, gills flapping in the current.
I’ve seen single animals in the past looking like this, and the first dive this morning I thought it might be crabbers chopping them up and tossing them off the rocks.
Then we did our second dive in an area closed to fishing, and in absolutely amazing numbers.
The bottom from about 20 to 50 feet [6 to 15 meters] was absolutely littered with arms, oral discs, tube feet, gonads and gills … it was kind of creepy.”
Then we did our second dive in an area closed to fishing, and in absolutely amazing numbers.
The bottom from about 20 to 50 feet [6 to 15 meters] was absolutely littered with arms, oral discs, tube feet, gonads and gills … it was kind of creepy.”
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Another recent starfish die-off occurred in the North American's east coast.
Something’s killing off the starfish. From Maine to New Jersey researchers have been noticing a decline in starfish populations – more properly known as sea stars – and a group of scientists from Rhode Island are trying to find out why.
Just a few years ago, there had been a boom in starfish populations, to the point that they were regarded as a pest to clam diggers, oystermen, and fishermen. Now there are hardly enough left to study.
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Starfish overpopulation to blame?
Canadian Broadcasting Corporation’s CBC News reports that some scientists suspect that the recent population boom may be part of the explanation for the die-off - being referred to as Sea Star Wasting Syndrome, or Starfish Wasting Disease.
As a population increases in size, food and nutrients may become scarce, stressing individuals and making them more susceptible to disease. Environmental factors such as weather may also offer an explanation.
Others suggest that recent heavy rains may have changed the water’s salinity, adversely affecting sea stars. Other possible causes such as warming ocean waters due to climate change, bacterial disease, and parasites are being investigated.
As invertebrates living in tidal areas, sea stars are particularly sensitive and die-offs may indicate environmental change.
Read more - http://healthmap.org/site/diseasedaily/article/marine-scientists-investigate-massive-sea-star-die-101013
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Could environmental changes caused by nuclear waste being spewed from Fukushima for two and a half years have something to do with it?
“Post-Fukushima Horror”: Severe impacts on oceanic environment — An unpredictable amount of damage to Pacific — Japan’s simply dumping nuclear waste into sea.
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A more sinister possibility?
Environmental pollution is very high on the list of suspects. But there could be other reasons. After all, the fishing industry considers them a pest and a competitor. Could a starfish-targeted poison be the culprit?
Simple. Wikipedia: "Because starfish like to eat clams and oysters, fishermen who gather shellfish have tried for years to get rid of them. To kill the starfish, fishermen would catch them, slice them right in half, and throw them back in the ocean. However, because starfish can grow back parts of their bodies, they were actually increasing the number of starfish."
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Why we should be concerned about the mass starfish die-off
The starfish species being lost now are unique to North America's west coast.
Microbes may be the cause OR they might be the RESULT of some shift in their surroundings, such as temperature or overall water quality. Sea stars DO have a natural microbial fauna.
What if that fauna/flora goes bad because of changes in some greater part of their environment?
Sea star wasting disease - http://www.eeb.ucsc.edu/pacificrockyintertidal/data-products/sea-star-wasting/index.html#track-disease
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