It seems like we never get enough good news when it comes to the environment in general, and to marine life in particular, but here are some for balance: starfish – or sea stars – have made an incredible comeback in along the Northern California coast.
This is the first boom in their population since a deadly virus decimated a huge number of starfish along the West Coast some years ago.
According to a new report from Oregon State University researchers, tons of juvenile starfish made it through the summer and winter of 2015, and their numbers are unprecedented.
Reports say that the number of baby sea stars found on rocks along the Oregon coast surpassed the normal records by 300 times. A roughly similar abundance was also discovered on the California coast by another team, the researchers at the Humboldt State University Marine Lab.
Starting in 2013, a virus called “sea star associated densovirus” caused a lot of sea stars to die off. Back then, scientists concluded the virus had been present but mostly dormant in West Coast sea stars for decades.
In 2014, PBS News Hour reported that the virus was spread with the help of a population boom, lying waste and death in incredible numbers. Some experts added that warming waters could also contribute to the exacerbation.
However, that hypothesis was not unanimously accepted, because further research concluded the virus seemed to flourish the most during the colder months.
Two years ago, researchers reported that even though many densoviruses are not deadly to their hosts, this particular one appeared to attack the immune system of sea stars, weaken it and causing the disease and the mass die-off.
The following reports only brought more bad news; between 2013 and 2014, the coast between Alaska and Mexico was cleared off of almost 95 percent of sea stars. In these conditions, it is understandable that the new data is encouraging.
After the disappearance of the starfish, the marine ecosystem was gravely impacted. Usually, starfish feed on sea urchins, and when the sea stars were no more, the urchins started devastating sea kelp forests.
Even though the densovirus remains present in starfish, researchers report that environmental factors have altered its effect on the starfish population.
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