The blob, deconstructed

I tell ya. You spend your days toiling away doing clever experiments, discovering new species, burning the midnight oil to prepare inspiring lectures for skeptical college students, crafting compelling grant proposals, solving the world’s environmental problems, pushing back the frontiers generally. Typical professor stuff. But what do people want to hear about?


No, not the giant amoeba-like alien that terrorized the small community of Phoenixville, Pennsylvania. I mean beach blobs. Let me explain.

There I was —  minding my own business faithfully fulfilling one or more of the aforementioned duties, and I get a call from our publicity guy Dave Malmquist. This was a few days after Hurricane Irene blew through. “A reporter from Virginia Beach wants to know what the gray blobs are all over the beach. Some local residents think it’s [word that cannot be used on a rated PG blog] that washed up from a navy ship.” Dave’s crack investigative work had already determined that they were probably sponges. I delved into some internet research for 3 or 4 minutes and concurred.

“They’re potato sponges” (Craniella sp.). So Dave responds to the reporter. I have to leave town (unrelated incident) and my buddy Mark Patterson is called into service by local TV station WAVY for a video demonstration to quell public anxiety (but they deleted his comments about poo and evolution. Hmm).

Dave posts the story on our website. A guy from the LA Times (LA??) contacts me. The blobs, evidently, have legs. And they take off running. Not literally of course. But to the Christian Science Monitor, LA Times, MSNBC, UPI, Britain’s Daily Mail for cryin’ out loud, and so on.

So, for the record — and so Americans can rest easy tonight —  here is the official story of Hurricane Irene and the blob:

 “They’re potato sponges” says Duffy, a self-professed “friend of the sponges” . . .  like other sponges, potato sponges make a living by filtering microscopic food from seawater. They draw the water into and through channels in their porous bodies by the beating of countless tiny hairs (flagella) on their cells.

Potato sponges, which comprise a diverse group within the genus Craniella, are normally inconspicuous animals (yes, they are animals) that inhabit shallow coastal habitats around the world, growing to about the size of a soccer ball. They look like, well, potatoes and attach to the seafloor with a network of protein fibers and glassy, needle-like “spicules” that form something like an anchor.

The blob in cross-section

But when weather conditions cause large waves and strong currents to scour the seafloor, they can dislodge large numbers of these sponges, freeing them to float to the surface and wash ashore. Clogged with storm debris and no longer able to filter feed, the sponges die. Then they start to smell as decay and bacteria move in to consume the carbohydrates and collagen that form their body.

Potato sponges are not poisonous—Dr. Duffy even found a recipe for potato sponge cake on the Food Network (but it turned out to require regular potatoes). Nevertheless, VIMS scientists caution area residents to avoid touching them as a precaution, as their glassy spicules can irritate the skin and eyes.

Good night,  and good luck.


One Response to “The blob, deconstructed”

  1. I am so pleased a collegue directed me to your post.

    On Assateague Island National Seashore in Worcester County, MD the masses that washed up post Hurricane Irene were similar to the mass in the website link I am hopefully sending (if I did this right). I know you are extremely busy but I appreciate you confirming that this image is of the genus Craniella like the ones you saw in Virginia. ???

    Thanks for sharing your expertise!!

    With gratitude,
    Christina Hulslander
    Assategue Island Alliance Program Manager

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