It’s the Season for Second (and Third) Looks at Drift Bull Kelp

Fall signals the end of the bull kelp Nereocystis growing season and the beginning of a period marked by the appearance of drift kelp masses on the beaches. Nereocystis is an annual, so it’s a wonder the growth needed to produce those massive tangles occurs in just a few months. Bull kelp stipes (the slender stems) can grow to 20 m or more in length! The annual sequence of kelp growth and senescence is integral to the beach food chain. Beach-dwelling creatures and migrating shorebirds depend upon it. You can sense the beach hoppers perking up when the kelp begins to wash ashore. This year’s cycle has started, and I’ve been fortunate to cross paths with several bull kelp masses already. So here (in three looks each) are my photographic slants on two of them.

On September 29, 2022, I came across this tangle after the tide and waves pushed it high enough for the beach hoppers, enthusiastic little amphipods, to begin having their way with it. (They consume it and take cover in and under it.) On the decay spectrum, it’s showing signs. Illustrating my natural framing tendency for beached bull kelp, the upper left-hand panel weighs a beach-level view of the kelp against the scene to the southwest across the beach to the surf zone and beyond. The upper right-hand panel is more from above, which often isn’t too interesting, but I don’t mind the perspective in this case. Finally, the lower panel, well, I’m always looking for scenes like that; the allure of bull kelp’s decay is arresting.

This drift giant arrived overnight, and we met up the following morning, September 30, 2022. For the time being, it settled lower on the beach than the other mass, with no noticeable sign of beach hoppers. On the decay spectrum, it’s fresher, even possessing some of its blades. The view shifts to the north to include a distant headland in the upper left-hand panel. Pneumatocysts (the bulb-like floats) and their remaining blades resting on swash-cleaned sand are the themes of the upper-right-hand panel. Backing off, the lower panel features elegant kelp stipes on an immaculate background.

The annual cycle of bull kelp death and beach renewal illustrates the interconnectedness of sister ecosystems.

Click here to see more sea wrack discoveries from September 29 and 30, 2022.

One Subject Three Ways


  1. Your posts always teach me something, Steve. Thanks for that. My favorites here are the images with the sun/sky/sea in the background, but I’m clearly not a marine biologist!! Fascinating post.

  2. I always learn something new when I read your posts, Steve! I didn’t know they were annuals, however I did notice more washed ashore when I was at Long Beach earlier this month.

    1. Isn’t it amazing they can put on that much growth between like March and September? You can find dift bull kelp any month, but it’s more prevalent September through winter. I like this time of year on the beach because the washed up kelp is fresher than later on in winter.
      ps- I love your shot (from Treasure Hunt) of Daisy in the driver’s seat hauling Max! So cute.

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s