Update, May 27: Thanks to a “super moon,” we’re having super-low tides around Seattle, just in time for Memorial Day weekend, 2021. (This low tide article was originally published May 31, 2018.)
A few days a month, Seattle’s beaches offer a glimpse into a world we seldom get a chance to see. Extreme low tides pull down the water level, revealing a colorful, varied group of plants and animals that spend most of their time under the surface of Puget Sound. Almost any of the beaches that line our city’s coastline can reveal wonders, if you know where to look.
Speaking of knowing where to look, find a great spot near you: 8 great Seattle-area beaches to explore at low tide. And for even more fun, here’s when and where Seattle Aquarium naturalists will be out to sneak a little learning (and more fun!) into your beach walk.
Track the low tide
The tide goes in cycles. Sometimes it doesn’t move very much, and about twice a month it fluctuates hard, with high highs and low lows for a few days at a time. To find out when those times are, check a tide table. I like this one, but there are a variety of others, as well as free apps for your phone. On the tide table, the lower the number the better. Negative numbers are great. The very best tides are -2 feet or lower. Plan to be on the beach at least half an hour before the time of the lowest tide.
Handle with care
Whether they bear tentacles, exoskeletons, fins, or tiny hydraulic feet, the animals that live by the low tide line have one thing in common that you should keep in mind. They are vulnerable. During low tide, most are trying to avoid drying out in the sun, so if you find something in a pool, or under a piece of seaweed or a rock, it’s important to put it exactly where it came from. Also, before you touch anything, be sure to rinse your hands in sea water. This is because sea creatures do not need your soap or sunscreen residue. Also, keep in mind that it is possible that a scared creature will fight back. Crabs can pinch, and some worms and octopuses can bite.
At low tide, if there’s a firm surface, some plant or animal will be living on it. Looking at rocks near the low tide line, you could find clusters of seaweed, snails, eggs of various creatures, limpets, chitons (like snails, except with eight interlocking shells instead of a single one), mussels, sea stars, anemones and barnacles (take some time to find some barnacles under the water. You could have a chance to watch them feed by opening their shells and scooping out plankton with their legs, or cirri). Don’t move any rocks that are too big for you to lift easily.
If you do carefully lift up a rock, you might find a variety of crabs, sea cucumbers, and even fish, such my favorite, the Northern clingfish, a creature that has a giant suction cup on its belly to hang on to rocks, and an ability to breathe air in an emergency.
Pools can reveal a variety of other creatures going about their underwater business: anemones, feathery tube worms, hermit crabs ambling about. It is best to sit and quietly watch for a bit, to see what comes into view. If you are lucky, there might be an octopus.
On sandy beaches, the scene looks very different. Sand doesn’t stay still, so animals who live in it to find ways of hanging on. Clams burrow under the surface. (Don’t try and grab one. They can shed their siphon to get away from you.) Sand dollars take sand into their bodies to anchor themselves. And pizza-sized sunflower stars spread themselves out over the shifting surface. A sea grass called eel grass anchors itself in the sand with a stout rhizome, and many creatures get by by hanging on to the eel grass. (Don’t walk on it.) Fish dart around in pools, and every rock teems with life.
Don’t forget to look up
When checking into the private lives of sea anemones and hermit crabs, it is easy to get caught up in the damp world at your feet and forget what is around you. Try not to do that, because there is a lot to see at the beach, including harbor seals surfacing off shore, gulls dropping clams on the rocks, and ospreys diving for fish.
As any toy marketer will tell you, kids love to collect. It starts in the preschool years and continues right up to middle school and often beyond. The same drive that leaves many kids to collect stickers or Pokemon cards shows up when kids come in contact with nature. There are some who never come back from an outing without having their pockets full of rocks and shells and whatever else occurs to them. Picking things up, examining them, comparing them to other things they picked up: these are all activities that help kids learn about their world and develop an interest in nature.
But in the vulnerable world of a low tide beach, you need to follow a couple of rules. One is that whatever gets collected should not be alive or have living things attached to it. No barnacles, no sea weed, and no orange crusty stuff (that’s alive too). The other is that you should leave the beach as you found it, so that means leaving almost all shells, rocks and pieces of driftwood in place.
However, I think it is fine to take the occasional precious thing: a perfect shell or a beautiful rock. But before you leave, most of what you collect should go back to the beach it came from. That doesn’t mean your child can’t keep a larger collection temporarily. My kids would often gather shells or rocks, take them up to a beach log, and sort their collections. You can add to the experience by providing a simple field guide. Mac’s Field Guide to Northwest Coastal Invertebrates is useful for shells. A Field Guide to the Identification of Pebbles is wonderful for your young rock-hound. Once the big sort is done, the collection should go back to the beach.
There is one category of things that you should to take off the beach: human-made objects, especially cans and plastic. There is no beach in Puget Sound that isn’t strewn with plastic, which is very harmful to wildlife. Do the beach a favor, and pick up litter as you find it.
Low tide pro tips
Your kids will get wet and dirty. You will get wet and dirty. If you travel to the beach by car, your car will get wet and dirty. Come prepared for an infusion of sand, muck and possibly seaweed. Wear shoes you don’t mind getting wet. No open toes. Barnacles grow everywhere around the lower tide line and they are sharp. Speaking of sharp barnacles, don’t forget the first-aid kit. And use a lot of hand sanitizer. Sadly, pollution is a feature of urban beaches.
Fiona Cohen is the author of the “Curious Kids Nature Guide: Explore the Amazing Outdoors of the Pacific Northwest.” She lives in Seattle. Her favorite Seattle-area beach is Discovery Park.