Leave them alone. They’re trying to clone!

Although they are animals, sea anemones are as lovely as the flower they are named after. Their colors range from red through orange, white, and green, some are even marbled in two tones. Tentacles fringe the perimeter, in the center is the orifice, or mouth. Sea anemones belong to the phylum Cnidaria. Because this group of animals lack a two-ended digestive tract, the mouth also functions as their anus.

At Pacific Science Center's Puget Sound Salt Water Tide Pool, we encourage you to touch the tentacles, which are used to sense and manipulate food and to defend the animal. We ask you not to touch the orifice! And now that you know what it is for, you probably don’t want to.



Sea anemones are normally round. But recently we have had a large number of anemones become elongated in one direction and narrow in the other. They look for all the world like rubber bands being stretched out tight.

These are one type of anemone, Anthopleura elegantissima, the aggregating anemone. While anemones can reproduce sexually by releasing free-swimming gametes into the water, many types also reproduce asexually. In the case of the aggregating anemone, the animals clone themselves. The stretched out individuals are part way through the process. Their two ends will each become a fully functional animal. The area in the middle thins until it eventually disconnects, freeing two daughter organisms.


Clonal groups of these anemones will often populate a large rock or flat area on a beach. When two groups meet, they use special stinging cells to battle each other. Don’t worry! None of the anemones in our exhibit is known to have a sting that can be felt by humans.


So when you see an anemone in the midst of cloning, please show it a little extra care. Cloning is fascinating, but it is also risky and costly of the animal’s resources. Choose another anemone – a round one – to touch. Though in a different way than we are used to, it is reproducing, and needs an extra bit of privacy.
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On the Beach

Taking advantage of the remarkably low tides recently, a group of Science Interpreters, Discovery Corps members and Life Sciences staff visited Discovery Park's North Beach on an extended lunch hour. Discovery Park is Seattle's largest park, has a City Park Marine Reserve, and is a close drive from Pacific Science Center. he purpose of our field trip was observational and educational. Because our Saltwater Tidepool Model features Puget Sound animals, we wanted to see them in their natural habitat. Furthermore, we become better spokespersons for their care and wellbeing and bring added insight to our interpretation. With firsthand knowledge, we can help our visitors practice their tidepooling manners for the next time they visit the beach.

　

As we carefully stepped along the sandy shore, we observed colonies of aggegating anenome (Anthopleura elegantissima) congregated within a couple of feet of each other. Scientists have studied warring behavior between aggregating anenome colonies of different genetic composition.

Upon closer inspection, Science Interpreter Gail noticed that the anenome tubercules were covered with tiny bits of shell and sand. This debris protects the anenome from sun damage and helps conserve moisture when the animals are exposed at low tide.

We also noticed an abundance of "clam shows," a dimple in the sand that indicates where a clam has withdrawn its siphon. The pressure from our footsteps on the sand set off a lot of "spitting" from the bivalves buried below. Along the lowest edge of the tide line we noticed a long line of exposed geoduck (Panopea abrupta) siphons. We could only imagine how far beneath the sand these giant clams rested - or how large they must be.Unfortunately, we did not see any sea stars or sculpins on this sandy beach. But at the high tide line boulders were covered with seaweed, kelp, mussels, barnacles and more anemones.The exceptional find of the day was ayoung harbor seal (Phoca vitulina) haul out. Observing this protected marine mammal gave us an incentive to learn about their behavior. Our encounter was a reminder that humans are just visitors to the beach. Seashores are homes to many sea creatures, large and small, which all need our respect when visiting their habitat.

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