We made a trip to Oregon in mid-June, and visited several beaches and tide pool areas from northern California up to Otter Rock, Oregon (which is just north of Newport).
Last September, we visited Otter Rock and spent about an hour wandering around at the fantastic tide pools just below the inn. The Ochre Sea Stars (
Pisaster ochraceus) were in good numbers and seemed healthy and happy (as a sea star can seem).
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| Ochre Sea Stars at water's edge, September 2013, Otter Rock, Oregon |
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| Otter Rock, September 2013 |
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| Otter Rock, September 2013 |
This June, we saw no truly healthy looking Ochre Sea Stars, although we did see a fair number of individuals of this species. They all looked withdrawn at the least, or "half-melted" in more dramatic cases.
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| Otter Rock, June 2014 |
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| Otter Rock, June 2014 |
A biologist at the Hatfield Marine Science Center confirmed that the disease has been detected in the area very recently.
In contrast, the rest of the tide pool ecosystem seemed healthy to our fairly untrained eyes.
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| Purple Sea Urchins were very abundant and filled the bottoms of some tide pools. Otter Rock, June 2014 |
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| Leopard Nudibranch, Diaulula sandiegensis, Otter Rock, June 2014 |
Ochre Sea Stars are often used as an example of a keystone species in ecology lessons, as they eat mussels, thus reducing the coverage of the rocks by these bivalves, and allowing a greater diversity of species to live in a given area. Without Ochre Sea Stars, mussels tend to become so abundant that they take up vast areas of prime intertidal "real estate", forcing other species out of the area.
We saw what appeared to be new crops of baby mussels at Otter Rock - likely a trend to follow the demise of the sea stars.
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| Small California Mussels, with Gary's feet for scale. |
Happily, at Humbug Mountain State Park, further south on the Oregon coast, we saw very healthy (and hungry) Ochre Sea Stars. I had never seen so much mussel-eating before!
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| A hefty California Mussel just visible underneath this healthy Ochre Sea Star. Humbug Mountain SP, Oregon. June 2014. |
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| Another sea star looking suspiciously like it's dining on mussel. Humbug Mountain SP, Oregon. June 2014. |
Now the sea star wasting syndrome has hit our San Diego coastal area, so it may experience dramatic changes in the months and years to come, also:
http://www.utsandiego.com/news/2014/Jun/20/environment-sea-star-wasting-syndrome-san-diego/
When I first moved to San Diego County with my family in 1977, and for years after, I never found sea stars of any kind at the tide pools in La Jolla and elsewhere locally, and only in the '90s and 2000s did I see good numbers of sea stars here in the San Diego region. Perhaps the trend will be a reversal to what I saw in the seventies, at least for a while.
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