Thursday, May 8, 2014

What's killing the sea stars?

This is my favorite animal.
There are a ton of reasons that I love Riftia pachyptila, most of which have to do with their unique biochemistry and physiology that allows them to live on the bottom of the ocean near, even on top of, hydrothermal vents. They aren't the only weird creatures that I love, I have a soft spot in my heart for any animal without a backbone, so you can imagine how my heart sunk when I pulled this issue of Science out of my mailbox.
There is an epidemic affecting sea stars on the west coast, starting with the most vulnerable deep water species, but affecting those in intertidal areas as well.  This condition causes white lesions to form on the animal, the tube feet die, and in later stages the arms start to break off. Several large aquariums on the coast have seen their star populations decimated, as the unknown disease causing agent enters their tanks that are fed by ocean water.

Scientists at universities around the country are using genetic testing to try to identify the pathogen (suspected to be either a virus or a bacteria), by comparing the bacteria present in healthy and sick animals.  Scientists are starting with bacteria because methodology for testing for bacteria is far less costly than that for viruses.

When we were at Olympic National Park in Washington state, we saw the starfish as thick as they are in the picture above.  We lost count of all the stars, anemones, and other invertebrates we saw while we were picking our way through the tide pools.  It's my sincerest hope that scientists will be able to identify and stop this pathogen in time to save this fascinating family of keystone predators.