PREVIOUSLY: LoCO CHALLENGE: What is This Pink Stuff Lining the Shores of a King Salmon Canal?


The pink stuff, close up.

It started, as you remember, with a Lost Coast Outpost reader sending along a photo of some pink gunk on the shore of a King Salmon canal and asking: What is this stuff?

Readers had their theories: Algae. Bacteria. Crabs. Krill. Nuclear waste.

And then the most amazing thing happened. Yesterday, during KHUM’s regular “Coastal Currents” program, Humboldt Baykeeper Executive Director told KHUM’s Mike Dronkers that she had put together a crack team to investigate the mystery. Last night she sent us amazing images from a digital microscope at an HSU lab, along with a precis of her team’s methodology.

Vanessa Vasquez (HBK), Shannon Hinrichs (Humboldt County Environmental Health) and I met out at the pink fuzz site, which is now more of a brown color, and took some samples. Frank Shaughnessy kindly offered to put it under the microscope at the HSU lab. Anthony Baker helped us out with some pretty fun digital microscope photos and! a mini-movie, in which you can see one long algae moving past the pink stuff (and other creatures darting around). 

We still don’t know what it is!  But, the long green filaments are a kind of blue-green algae (cyanobacteria) from the genus Lyngbya. (sorry probably not a Scrabble word).  These are photosynthesizing bacteria. The pink stuff — all we can say at this time is each ball of it is probably a colony of smaller bacterial cells.  Frank has a colleague who may be able to say more, so the lab kept the sample. If we hear more I’ll let you know.

So: No definitive answer yet! Stay tuned! In the meanwhile, though, check out the additional pink stuff imagery below, and remember — if something like this is puzzling you, the Lost Coast Outpost WILL get to the bottom of the case. Maybe. Send your inquiries to

Thanks, Baykeeper and Environmental Health and HSU!

Below: Baykeepers scooping up the stuff.

HSU Botany Professor Frank Shaughnessy eyeballs the pink stuff: