Know your beach—this week from the beach

#1 in the 2018 series of guest blog posts by Seattle Aquarium beach naturalists Bobby Arispe and Jen Strongin.

Message from Jen:

Welcome! I am so happy to be back with my co-blogging partner-in-crime, Bobby Arispe, to bring you to the beach with us throughout our season this summer. If our beach trainings are any indication, this summer is going to be an especially good one! Did you know the Seattle Aquarium Beach Naturalist program has 240 amazing volunteers who dedicate their time during the spring and summer months to educate visitors at our local beaches about all of the wonderful animals that we share our local shores with? And that you can see a sea star or a nudibranch or maybe even an octopus on a beach within the Seattle city limits? You can. We live in such an amazing city!

Training for new beach naturalist volunteers starts in March and culminates in May with an evening of guest speakers and the distribution the beach naturalists’ signature red caps. By the time our new volunteers hit the beach, they have been schooled in beach biology, interpretation, the importance of the nearshore, the salmon life cycle and how to be good stewards of our local marine environment.

Know your beach-this week from the beach

Come along with me, and I will show you some of the wonderful animals we saw during our trainings last month.

On the way down to the beach at South Alki, we saw a mama killdeer guarding the eggs in her nest. A regular at our spring trainings, she’s good reminder of the connection between the nearshore and the intertidal zone.

We know it’s spring when we visit the beach at low tide and see lots and lots of moon snail egg collars. Reminiscent of clay pots or discarded toilet plunger bottoms, these casings—made of sand, mucus and eggs—contain over half a million baby moon snails, getting ready to hatch out. They make a great shelter for other animals too and you never know what you might find if you turn one over (just make sure to turn it back!).

During our training at Saltwater State Park, we found this gorgeous, rainbow-colored polychaete worm on the underside of a moon snail egg collar!

This empty moon snail shell was home to so many animals! A juvenile red rock crab thought it made a great hideout.

An opalescent nudibranch thought this shell was the perfect spot to lay his/her eggs. Don't overlook the barnacles and that teeny snail who decided to call this old shell home too. Just like up on our urban streets, housing is tight in the intertidal zone.

We do a lot of beach CSI during training, looking for evidence of various animals on the beach and learning about them. The countersunk hole in this clam shell is clear evidence that a moon snail has been here. Using its large foot, a moon snail will grab hold of an unsuspecting clam and move it into position. Next, the moon snail excretes special enzymes/acids that soften the shell so it can make use of its special tool: the radula. This secret weapon is a tongue-like organ with hundreds of tiny sharp teeth, excellent for drilling holes and scraping out bits of delicious clam meat from the shell.

A face only a mother could love? Hmm, well we naturalists love it too! I mean, look at those awesome teeth! Some of our new naturalists got to learn all about the plainfin midshipman at our Saltwater State Park training. The males are often found high up in the intertidal zone, under rocks, guarding their eggs. They can breathe through their skin and are able to spend long periods of time out of the water at low tide. Don't be alarmed when you see one, they are exactly where they should be—with their eggs!

Midshipmen were given their name because of the small white dots on the sides of their bodies that reminded someone of the buttons on a military uniform. These dots are actually small organs called photophores. Photophores give the midshipmen the intertidal superpower of glowing in the dark! See, you love the midshipman now too, don't you?

I may have to declare this the summer of the leopard dorid nudibranch. We saw SO many during our trainings. They love to cruise the rocks, grazing on sponges as they go. One thing I learned this spring: the egg mass of a leopard dorid can contain up to 17 million eggs!

So, first of all, all of our fingernails look like this after a day of naturalizing at the beach, so don't judge, ha. Second of all, look at this tiny anemone on a blade of eelgrass! This is a brooding or proliferating anemone. They start off as female and transition to hermaphrodites once they mature. There are no true males among this species! Although they can reproduce by broadcast spawning, self-fertilization is common. When the babies are ready to hatch out, they come out of the anemone’s mouth, slide down the side and then stay there until they are ready to go off on their own. If you find one, look closely for little babies all along the base of the body! There are all kinds of animals that use the eelgrass for shelter and as a nursery for babies, including our beloved salmon. We do our best to walk around eelgrass so we don't crush anyone under foot. Beach etiquette tip: Walk around the eelgrass!

One more cool anemone observation from our time on the beach last month: The photo above is a plumose anemone out of the water with all of its feeding tentacles pulled in. However, we CAN see some other specialized tentacles here called acontia. These are super-powered defense tentacles, filled with extra potent stinging cells. This plumose anemone can shoot out these stringy tentacles from all over its body (kind of like Silly String) to defend itself against predators.

Here are some more photos from our days on the beach:

Bobby will be here next week with more photos and tales from our trainings. We are back out on the beach June 13 for some of the lowest tides of the summer. We look forward to exploring with you and sharing our love of the Salish Sea! 

Meet Seattle Aquarium beach naturalists on local shorelines this summer! Check our website for dates, times, locations and directions.

JenAbout Jen:

Jen writes:

“I ventured westward from Albany, NY and fell madly in love with our city from the moment I arrived. It was 21 years ago this August when Seattle first charmed me with its lush, forested parks, beautiful beaches, and water and mountain views (when the skies are clear enough) all around.

I signed up to be an interpretive volunteer at the Seattle Aquarium in 2013, became a beach naturalist volunteer in 2014, and this will be my third year as an official member of the Seattle Aquarium staff as a beach captain. My favorite place to be is on the beach, with my camera, sharing my love and knowledge of our intertidal dwellers with the hope that I will inspire others to love and protect the Salish Sea and the ocean beyond.”


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