Tuesday, June 2, 2009
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We also noticed an abundance of "clam shows," a dimple in the sand that indicates where a clam has withdrawn its siphon.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.