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SeanDav

> "Large accumulations of mussels can weigh as much as 1,700 pounds per square foot."

I really find it hard to believe that is a number based in reality.

Disclaimer: I am no expert!

EDIT: Even if the mussels were solid gold and it was a cubic foot of them, they would "only" weigh 1206 pounds.

source: http://www.coolmagnetman.com/magconda.htm

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A little digging around suggests 35kg per square meter is a more reasonable estimate[1], which is about 8lbs per sqft. I suppose it's possible some measures include the weight of the water in the mussels, and others don't?

1: https://www.boatdesign.net/threads/boat-weight-increase-due-...

That's ignoring the buoyancy from displacing water and only covers two years. I could see the worst case say a stationary house boat being vastly more problematic over 30+ years. But, they should generally fall off before the weight gets crazy.

It does seem hard to believe, perhaps they mean a square foot of mussels on a boat bottom causes drag equivalent to towing an extra 1700lbs?

I wonder if the author is confusing weight with drag. I could see mussels (and the algae they always bring with them) introducing more drag on the hull than their weight. But then again, I'm no expert, just a weekend sailor.

I had a mental image of a foot square patch of hull with a 200m long spire of mussels sticking off the side.

I'm pretty sure that's a typo in the article.

"It's weird. The chart says depth here is 200m, but we always bottom out."

Yeah, that's just a crazy number. It would be a crazy number if mussels were made of lead.

I'm guessing it is a typo of some form. One (or perhaps both) of the unit values are wrong. It doesn't takeaway from the fact that mussels are a huge issue, or the amazing way they have adapted to attaching themselves to surfaces.

Find a way to harvest the mussels and you'll need no food delivery at sea. /s

perhaps the square foot is only the footprint of the accumulation of mussels? They could extend out a pretty long way..

I just assumed cubic feet

Even a cubic foot of water would be well under 100lbs. I doubt a cubic foot of mussels + water to fill the rest could weigh a ton.

It may be possible for (especially stationary structures) to accumulate enormous columns of biofouling materials, but for such a layer to reach > 20 feet thick (possibly closer to 50 feet without counting the interstitial water) sounds unreasonable. But I'm not knowledgable in this area.

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