Rocks merging with Shells

[theonew]

Yesterday the wife and I went on a walk along the Hudson River, Jersey side, just north of the George Washington Bridge. We found these at low tide:

Pretty cool looking but I've never seen this before. Anyone know what causes this? Is it pollution related?

 

[paleojoe]

Nice finds!:thumbup:

I believe it can be a couple things that cause it... Shells, although primarily calcium, are made by mollusks, snails, etc. by extracting calcites, argonites, lime, proteins, etc. from their food and their own calcium-rich blood and excreted to build a shell. Many types of shells, as they are built, are cemented to objects and surfaces, like rock, or other parts of shell or even whales.
Some other shells, after they are discarded, become part of a sedimentary building process, so calciums and magnesiums, etc. build-up like they do in irrigation emitters or water boilers over time...

From what I can see, those look intentionally cemented and built upon the rock... I have a few similar looking ones as well!

 

[Mistwalker]

Oysters and barnacles always anchor themselves on something solid. I believe in order to feed on the microscopic particles in the passing over them in the flow of the ingoing and outgoing tides. If you look at the columns of peers and on the rock jetties they are usually just below the surface at high tide and just peeking out at low tide. Sometimes man made and weather incidents just cause some to become loosened and relocated. Cool find, I always like finding shells like that. I have found them in Mobile Bay and Tampa Bay.

 

[Moving Target]

Oysters.

 

[theonew]

I'm somewhat familiar with the anchoring of molluscs, these look different though. Almost like they are melting onto the rock. Just seemed strange to me.

Here's two shots of the one on the left:

 

[Marcelo Cantu]

You're such an alarmist Theo. I'm going to ignore these and other signs until it's too late.

 

[fujita yuji]

These are some cool findings.
Hard things like shell melted on rocks.
Very much interesting.
Thanks for sharing, Theonew.

 

[Marcelo Cantu]

Fujita yuji, I once saw a TV program (Carl Sagan's Cosmos) about a certain kind of crab found off the coast of Japan that have shells formed like warrior's faces. The legend being that they are the souls of lost chinese warriors's whose ships sank while trying to attack Japan.

They are not eaten by people.

 

[theonew]

They tasted pretty weird as well and now my left leg is glowing, should I be concerned

 

[jw2n]

Nah, just pretend it's a big chem light.

 

[fujita yuji]

Fujita yuji, I once saw a TV program (Carl Sagan's Cosmos) about a certain kind of crab found off the coast of Japan that have shells formed like warrior's faces. The legend being that they are the souls of lost chinese warriors's whose ships sank while trying to attack Japan.

They are not eaten by people.

Yes, that TV program is also quite popular here in Japan and I remember
the episode you mentioned pretty well!
It's called Heike gani(平家&#34809. Heike is a name of major household in
early fudal Japan (around 1100 AC), lost it's decisive sea battle held
around the area where these crabs accidentally (or necessarily ?) live, and
perished from history.