All that the tides reveal: Puget Sound’s hidden intertidal world


We Puget Sounders can enjoy many experiences and treasures in our region: things like temperate rainforests on the Olympic Peninsula, volcanic mountains bordering the sea, and some of the world’s most fertile agricultural land paved by ancient glaciers and biblical floods.

But among the most special, and perhaps most discounted, treasures is the Puget Sound itself.

On June 15th and 16th, beaches in our Puget Sound region had lower tides than they have seen in the past 13 years. Thanks to the lunar nodal cycle, the tides dropped more than 4 feet below mean tide level.

Depending on the slope of the beach, a low tide of this magnitude revealed hundreds of feet of seabed that can be explored without a wetsuit or snorkel.

The Puget Sound is one of the most unique bodies of inland sea water in the world. The bedrock that underpins its seafloor was carved into ancient mountaintops by giant Ice Age glaciers that would have long ago covered every major city in the region with thousands of feet of ice. The blue and green salt waters we know as the Puget Sound are one of the most biologically diverse marine ecosystems in the world. It is also a world famous diving attraction for this reason.

Don’t be afraid to get wet

Have you ever walked or driven along the shores of Puget Sound and wondered what otherworldly creatures were swimming, crawling, writhing, gliding, sliding, slithering, surviving and thriving just 30 meters from the coast?

The Earth, Moon and Sun have literally aligned to allow us land dwellers a rare glimpse into the underwater world. All you need to enjoy it is a pair of shoes that can get wet and a sense of childlike wonder.

On June 16th we explored the exposed seabed off the shores of Dash Point State Park. As the peak of low tide approached in the early afternoon, we dropped in and stepped on hundreds of meters of sun-kissed seabed to see what the tide would reveal.

On Dash Point 16 June 2022. Henry Stewart-Wood/Sound Publishing

We were not alone in our interest in exploring the treasures of the intertidal zone. Many others combed the beach around us. People young and old craned their necks and scanned every rock, pool and sandbar, hoping to catch a glimpse of a sea creature, out of place and stranded by the rhythm of the sea tide.

The beach at Dash Point was more sandy than rocky. There were very few rocks. In my experience with the tide in the Pacific Northwest, rocks can usually be turned over to reveal a community of sea creatures that use the rock and a small pool of water as shelter from the unforgiving sun.

Instead of boulders, this beach had sprawling beds of sea grass. The grass looked squashed and flattened out of the water. Gulls and herons gathered among the grass at the edge of the receding shore, scouring the aquatic foliage for crabs and other invertebrates that weren’t fast enough to escape with the tide.

Along with a bunch of crabs smaller than the size of a quarter, we found larger Dungeness crabs that died and were left to cook in the sun. We also found the molted exoskeletons of kelp crabs and what seemed like an endless supply of clams, each a relic of a mollusk’s life hunted by both marine and terrestrial predators.

On Dash Point 16 June 2022. Henry Stewart-Wood/Sound Publishing

On Dash Point 16 June 2022. Henry Stewart-Wood/Sound Publishing

One such predator, and one of the top predators in the Puget Sound seagrass bed ecosystems, is the moon snail. They are gigantic molluscs larger than the size of an average fist. Its soft body is so large that it cascades out of its baseball-sized shell.

Despite their large size, they can be difficult to find because they burrow under the sand as the tide recedes, but evidence can be found scattered along the beach.

They feed on clams and shellfish using a specialized drill-like tooth called a radula, which it uses to bore a hole through the hard shell of a clam or mussel so it can feed on the soft tissues protected in the interior Clams that have fallen victim to the moon snail can be identified by a very soft hole in the shell.

Many beachgoers have probably noticed the necks of moon snail eggs left on the shore, but may not have known what they were. We found several dozen on our trip.

They are ring-shaped collars that are gray like the sand they are made of. The snail uses sand and a mucus excretion to form a structure on which to lay its eggs. To the touch, they feel soft and waxy, almost like fruit skin.

The moon snail is one of the many alien creatures that can be revealed by the changing tides of Puget Sound, there are many different sea creatures to see, feel and discover, but you may have to get your hands dirty and the feet

On Dash Point 16 June 2022. Henry Stewart-Wood/Sound Publishing

On Dash Point 16 June 2022. Henry Stewart-Wood/Sound Publishing

On Dash Point 16 June 2022. Henry Stewart-Wood/Sound Publishing

On Dash Point 16 June 2022. Henry Stewart-Wood/Sound Publishing.

On Dash Point 16 June 2022. Henry Stewart-Wood/Sound Publishing.



Source link

Jennifer Ahdout

Jennifer Ahdout

Leave a Reply

Your email address will not be published.