Scientists started noticing the mass deaths in June of 2013
Both wild starfish and those in captivity have been affected by the mysterious phenomenon
Entire populations have been wiped out in Puget Sound
|
Starfish have been mysteriously dying by the millions in recent months along the US west coast, worrying biologists who say the sea creatures are key to the marine ecosystem.
Scientists first started noticing the mass deaths in June 2013. Different types of starfish, also known as sea stars, were affected, from wild ones along the coast to those in captivity, according to Jonathan Sleeman, director of the US Geological Survey's National Wildlife Health Center.
'The two species affected most are Pisaster ochraceus (purple sea star or ochre starfish) and Pycnopodia helianthoides (sunflower sea star),' he wrote in a statement in December.
Mystery: Millions of starfish on the west coast are dying - and scientists have no idea why
The sunflower sea star is considered among the largest starfish and can span more than a meter in diameter.
The most commonly observed symptoms are white lesions on the arms of the sea star. The lesions spread rapidly, resulting in the loss of the arm. Within days, the infection consumes the creature's entire body, and it dies.
Entire populations have been wiped out in Puget Sound off the coast of Washington state, in the Salish Sea off Canada's British Columbia as well as along the coast of California. The mortality rate is estimated at 95 percent.
Scientists who have spent decades studying the local ecosystem have yet to identify the cause.
'What we currently think is likely happening is that there is a pathogen, like a parasite or a virus or a bacteria, that is infecting the sea stars and that compromises in some way their immune system,' Pete Raimondi, chair of the department of ecology and evolutionary biology, at the University of California, Santa Cruz, told AFP.
+3
Wiped out: Entire populations of starfish have been wiped out in Puget Sound off the coast of Washington state
Then, the creatures become more susceptible to bacteria which is "causing a secondary infection that causes most of the damages that you see.'
A barometer of sea health
The 2013 phenomenon has not been observed solely along the West Coast; a smaller outbreak also killed East Coast sea stars last year.
Read More Here
.....
What's killing all the starfish on the West Coast?
A
starfish clings to a rock near Haystack Rock during low tide Saturday,
July 31, 2010, in Cannon Beach, Ore. (Rick Bowmer/AP Photo)
Scientists first started noticing the mass deaths in June 2013. Different types of starfish, also known as sea stars, were affected, from wild ones along the coast to those in captivity, according to Jonathan Sleeman, director of the U.S. Geological Survey's National Wildlife Health Center.
“The two species affected most are Pisaster ochraceus (purple sea star or ochre starfish) and Pycnopodia helianthoides (sunflower sea star),” he wrote in a statement in December.
The sunflower sea star is considered among the largest starfish and can span more than a meter in diameter.
The most commonly observed symptoms are white lesions on the arms of the sea star. The lesions spread rapidly, resulting in the loss of the arm. Within days, the infection consumes the creature's entire body, and it dies.
Entire populations have been wiped out in Puget Sound off the coast of Washington state, in the Salish Sea off Canada's British Columbia as well as along the coast of California. The mortality rate is estimated at 95 percent.
Read More Here
.....
Related articles
No comments:
Post a Comment
Hello and thank you for visiting my blog. Please share your thoughts and leave a comment :)