The end is nighSeptember 3rd, 2010 by Jeff Adams
School buses aren’t the only harbingers of summer’s end. The last daytime minus tides of 2010 will be over the next four mornings. The tides for Bremerton over the next few days are…
Saturday – 8:00AM, -0.3
Sunday – 9:00AM, -0.7
Monday – 9:50AM, -0.7
Tuesday – 10:40AM, -0.5
What a better way to enjoy a relaxing morning than a walk on the beach. Or maybe you could enjoy a morning shellfish harvest for lunch. Thanks to toxins from plankton (paralytic shellfish poisoning or PSP) and Vibrio bacteria, many of our beaches currently have health department restrictions or advisories. Check the Washington Department of Health Shellfish Safety website before you head out.
Not only are we losing our low tides, most of us in Hood Canal, central Puget Sound and Whidbey Island area are seeing our final days of crab season. Male Dungeness and red rock crabs await the boiler, but you’ll have to catch them first.
Sexing crabs is a pretty easy business if you can get them to hold still long enough to turn them over. The abdomen of a crab is one of the things that separates the different groups of 10 legged crustaceans.
In hermit, king, porcelain and related crabs, it’s asymmetrical, somewhat exposed and (in the case of hermits) soft enough to need a shell to keep important organs from becoming fish food. In lobsters and crayfish or even shrimp, the tail is symmetrical and large with powerful muscles.
True crabs, like the graceful, red rock, Dungeness and shore crabs we commonly see on the beach, have a symmetrical abdomen that is relatively flat and tucked snugly under their body between all their legs. The male’s abdomen is narrow, generally shaped like a triangle and only fills a portion of the space between the legs. The female’s is broad, filling most of the space between the crab’s legs. This broad abdomen helps her protect her eggs while she broods them.
I hope you had a fabulous summer and were able to enjoy all that water has to offer. Now that autumn is upon us, I hope to be a bit more regular about blogging. There is so much I’d love to share and to learn from you. Thanks and have a great weekend! JEff
Jeff Adams is a Washington Sea Grant Marine Water Quality Specialist, affiliated with the University of Washington’s College of the Ocean and Fishery Sciences, and based in Bremerton. You can follow his Sea-life blog, email to firstname.lastname@example.org or call at 360-337-4619.