[Tweeters] Shrimp Shadows

Jeff Gibson gibsondesign at msn.com
Fri Jul 8 08:23:45 PDT 2016








I've had a life-long love affair with shadows. To me shadows are wonderful, mostly.
There are those delightful moonlight shadows, when the moon reflects enough light our way. Hey, maybe there are star shadows on "moonless" nights in area's far from light pollution - I haven't noticed that really, probably lacking the eyesight.Maybe some sort of bird could. But not to worry because the King of Shadows will show up soon: our nearest star.
AKA the Sun. When the sun comes up we have shadows all over the place. Well, a little contrast helps. Sometimes the whole Wetside Pacific Northwest region is under the shadow of thousands of feet of clouds which subsumes all the other shadows. So it goes.
Anyhoo, mister shadowmaker was out in full force on this past sunny Wednesday while I snooped the low tide at Fort Worden. And I saw wonderful shadows. Shrimp shadows.
If you want to get to know our local marine life you could do no better than to read "Seashore Life of the Northern Pacific Coast" by UW professor emeritus Eugene Kozloff - a beautifully written book that really gets to the gist of our local marine biology. In that book he notes the shadow phenomenon of Mysid Shrimp, which helped affirm my first observation of these creatures on the sand flats at the mouth of the Skagit river several decades ago.
The deal is that the Mysid shrimp has a somewhat transparent body, and what isn't transparent looks like sand. On a sunny shadow maker day the shadow casting shrimp are nearly invisible in the sunlight over the sandy shallows - all you can see are their shadows on the sandy bottom. It's really uncanny. Schooling shadows.
Mysids, while puny (truly shrimpy) - like less than an inch long mostly- are an abundant crustacean and important link in the marine food chain.They swim in the water column like a small fish. I've seen thousands of them in huge swarms around the Port Townsend Marine Science Center floating dock, and also many at the beach I was at on Wednesday on previous wades. Thanks to my close-focusing binoculars I was actually able to focus on the actual shrimps, just barely visible, in their sandy transparent disguise.
There were a few bird shadows at the beach too, mostly Barn Swallow and gull shadows- it was a quiet high noon for birds.
Jeff Gibsonwatching shadows inPort Townsend Wa






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