A piece of a sea star, apparently Pycnopodia helianthoides, observed at approximately 45 foot depth in Port Angeles harbor on 20 August 2014
The Elwha sub-tidal SCUBA surveys that I participate in are designed first and foremost to help us understand how the Elwha dam removal influences the marine biological community in the nearshore areas adjacent to the Elwha River mouth. This year, though, we were also interested in any observations that might help us to understand how Sea Star Wasting disease is influencing sub-tidal sea stars in the central Strait of Juan de Fuca. Much of what has been reported on recently from the central Strait of Juan de Fuca is based on intertidal observations.
The synopsis: We definitely observed apparently infected stars (mostly, if not all, Pycnopodia helianthoides). We also observed plenty of apparently health stars (including Pycnopodia helianthoides), in some cases right next to, or near, dying stars. Some photos and video are below, collected at the sites shown on the map below, between 5 and 20 August 2014.
Our next step, hopefully, will be to use our baseline data from as far back as 2008 to test the hypothesis that some sea star species have declined in density in the past year at our sub-tidal sites in the Strait of Juan de Fuca.
Video shot at site D2 showing a dead or dying Pycnopodia helianthoides.
An apparently healthy Pycnopodia helianthoides from site D2.
Video shot at site F2 showing both an apparently healthy Dermasterias imbricata and a dead or dying Pycnopodia helianthoides.
An apparently healthy Pycnopodia helianthoides at site E2
A dead or dying Pycnopodia helianthoides photographed at the site marked "PA Harbor". This was near to the sea star leg shown in the photograph at top of this post, though it wasn't clear if the two photos were of parts of the same star.
An apparently healthy Evasterias troschelii at site J1
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