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Marine biology students kick off experiment at Titlow Park

June 14, 2017

Bellarmine Preparatory School students build artificial tide pool on the beach

The welcome mat is out at Titlow Park for a constellation of marine life that’s often invisible to visitors even when tides are low.

A crew of energetic Bellarmine Preparatory School students, parents and siblings has created an experimental refuge that they hope will attract a community of plants and animals typically seen in the intertidal zone. Construction took a little more than an hour during a Memorial Day weekend low tide.

Encouraged by Bellarmine teacher Ron Nilsen – “Hey, can I get some help here?” “How’s the digging coming?” –they dug sand and gravel out of a shallow pit and surrounded it with a barrier of barnacle-encrusted boulders pulled from the adjacent beach.

titlow tidepool project

The result was an artificial tide pool, about 10 feet long and in the shape of a peanut or dry kidney bean. The site on the rocky shoreline was chosen in part because of the relative absence of the kinds of critters encountered in naturally forming tide pools around Puget Sound.

Bellarmine senior Jack Martin designed the tide pool as a science project. He’s hoping it will attract a tiny ecosystem, potentially including kelp, sea weed, mussels, crabs, sea worms, sea stars, sea anemones, little fish and perhaps sea cucumbers. It could take as long as three years before it all comes together, he said.

If the tide pool project succeeds, it would offer a good way for beachgoers to observe marine life without disturbing it, he said. As it is, people often flip over rocks to catch a glimpse of a crab or other animal. When that happens, the animals may not survive.

Whether the tide pool itself survives is part of the ongoing experiment. The Titlow beach area where it is located is erosive, Nilsen said, so time will tell if the tide pool holds up against the current and wave action that shapes the shore.

For the next year, two other students, Claudia Modarelli and Dylan Rivers, both juniors, will continue the tide pool project as monitors. Their task is to periodically record its status and map evidence of life forms observed. They’ll be taking photos during low tides and also do some scuba diving.

“I’ll be looking for physical changes and to make sure it doesn’t cave in,” Rivers said.

Months before tidepool construction, Nilsen and Dave DeGroot, director of Bellarmine’s marine chemistry program, sought backing from Metro Parks, which secured the necessary permit from the state Department of Fish & Wildlife.

Titlow tidepool project

“Metro Parks is pleased to see the students and faculty interested in aquatic life,” said Tom Dargan, Metro Parks project administrator. “The kids and staff really did a great job in planning and implementing this fun project.”