Dawn Breaks on a Crustacean Clash

Three minutes before sunrise, a seemingly peaceful scene, but beach hoppers were tussling on the drift line.

5:59:11 am | The driftline is visible in the lower left corner

On the beach, the driftline was littered with seaweed debris. With the sun not yet shining brightly, and the air warm with almost no breeze, beach hoppers were out and uninhibited. If you’ve never hung out with beach hoppers, give yourself a treat. Pick a warm still morning and make your way down to the driftline around first light. If you’re not a morning person, Ricketts and Calvin offer a solution.

Observers with a trace of sympathy for bohemian life should walk with a flashlight along a familiar surfy beach at half-tide on a quiet evening. The huge hoppers will be holding high carnival– leaping about with vast enthusiasm and pausing to wiggle their antennae over likely looking bits of flotsam seaweed. They will rise up before the intruder in great windrows, for all the world like grasshoppers in a summer meadow.

Ricketts and Calvin (1968)
6:04:18 am | Beach hopper workings around and under drifted organic material

Active beach hoppers can devour patches of drift algae in a night or two, leaving only a ghostly outline of their workings in the sand. These are California beach hoppers, Megalorchestia californiana. Wherever they are abundant, you’ll soon find their isolated oval-shaped burrows. Males are famous for fighting over them.

6:05:36 am | Isolated burrows (looks like a new one under construction, upper right)

I’m grateful for the the opportunity I got to observe these two clash over burrow rights. For a few seconds I existed only in that world.

Two male Megalorchestia californiana in combat
6:05:41 am
Megalorchestia californiana, battle still on
6:05:44 am
Megalorchestia californiana, here both combatants flipped over
Megalorchestia californiana, back to wrestling

The battle ended without warning. I’ve never wished more for the ability to read crustacean body language.

Megalorchestia californiana, fight's over
6:05 :49 | It’s over. Who won?

Around sunrise males, and pretty much all the hoppers, retreat to burrows or seaweed shelters. I watched the fellow below search for something suitable. At the time, I didn’t notice rival antennae poking out of all the nearby entrances.

A male Megalorchestia californiana on the surface; three occupied burrows visible (only the antennae sticking out)
6:06:35 | Nearby burrows occupied

My guess is the burrows shown here were constructed the previous night, the night of the highest tide of the cycle. With lower water in the forecast, these burrows had a chance to last a while. Maybe that’s what made them worth fighting for. Still, I wonder what goes on in there.

6:06:38 | Movin’ on

By four minutes after sunrise all the big males had retreated to burrows, or were working on it. Activity was slowing.

Male Megalorchestia californiana, diving into a burrow
6:06:42 | With some renovation this one might do

The hoppers needed privacy. Low tide was less than an hour off. It was a good time to turn my attention to the tidepools. Incredibly, I was with the hoppers less than four minutes!

6:08:06 | What will the tidepools reveal?

The first time I connected with California beach hoppers in person was in June, 2013. I tell that story and share a few photos in California Beach Hopper, Megalorchestia californiana.


Kozloff, E. N. 1993. Seashore Life of the Northern Pacific Coast. 3rd ed. University of Washington Press.

Ricketts, E. W., and J. Calvin. 1968. Between Pacific Tides. 4th ed., revised by J. W. Hedgpeth. Stanford University Press.

Online Resources

Check out The Invertebrates of the Salish Sea’s page on Megalorchestia californiana


  1. Love this post so much. The picture with every hole occupied by a pair of antennae was awesome. Great natural history!!

    1. Isn’t that the coolest? Thanks for taking the time to mention it. The wrestling match was epic. What I showed was only about 8 seconds. I watched about two seconds longer.

  2. That was a fun read with some cool shots. Thanks Steve. These are different than what I hear referred to as “sand fleas” right?

    -Chris ____________________________ Chris Allen Acting Aquatics Division Manager USFWS, Oregon Fish and Wildlife Office 2600 SE 98th Avenue, Suite 100 Portland OR 97266 Phone: 503.231.6906 chris_allen@fws.gov

    1. Thanks Chris. Good question. People do call these sand fleas. I favor beach hoppers. And, these are the biggest of ours in Oregon. There is a super common smaller version too. Looks similar, but males lack red antennae. And there are a few other less common species too.

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