Can someone get stuck in a giant sea clam?

[Shipwreckscanada]

I just saw episode 39, “The Manganese Story” from the TV series Sea Hunt. In it a diver gets his leg trapped in a giant sea clam. They can weigh more than 200 kilograms (440 lb).

In the TV show the diver got out before his air expired but I started wondering if this can happen in the real world. I guess the diver would have to cut off his leg or die, ouch.

They sure do look beautiful.

 

[TMHeimer]

Actually I googled that a long time ago. Basically it said no. The giant bivalve opens and closes so slowly you'd have to have your leg in there for an awful long time for it to close on you...but, you know Darwin....

 

[CuzzA]

Being that bivalves are a real pain to open just to eat I imagine it would hurt. They have quite the powerful muscle, but clams actually have to use energy to close. Contrary to what most would assume, relaxed is open and using energy flexing muscle is closed. So given that they only have so much energy, a leg kicking inside would surely hurt it and being that you would have some leverage because the shell wouldn't be fully closed, I imagine you'd be okay. I wouldn't go sticking any body part inside of a clam to find out though.

The species that actually gets big enough for a human leg would be a Giga or Derasa Clam. I believe the picture you linked is a Maxima and they only reach ~12". I have both a Maxima and Derasa in my reef tank (maricultured). They are beautiful. Here's a pic of my Maxima. My fish store has a ~30" Derasa in their 300 gallon display, it's quite incredible to see how big they get.

TMHeimer is right though. Derasa's/Gigas' are very slow. However, some of the other Tridacna clams are quick. I've seen images of fish meeting their demise by trying to snack on a clam and it slamming shut.

 

[CT-Rich]

Yes, just remember that giant clams are attracted to RED. That is why you always make your dive partner wear the red rental wet suit....

 

[EastEndDiver]

Just remember you don't have to outswim the clam just your dive buddy.............

 

[Bob DBF]

I have no experience with giant clams, however an Abalone can close fast enough to trap your hand if you are taking one by hand rather than using an Ab bar.


Bob

 

[eeel]

If you read Southsea Adventure by Willard Price as a kid you would have been haunted by this possibility.

 

[MXGratefulDiver]

A few years back there was a report of a snorkeler getting her hand trapped in a giant clam in Bali (Tulamben, I believe) and drowning ... not sure if it was true, but I do recall reading the report ...

... Bob (Grateful Diver)

 

[Eric Sedletzky]

I have no experience with giant clams, however an Abalone can close fast enough to trap your hand if you are taking one by hand rather than using an Ab bar.


Bob

I've pulled abs before with no iron by sneaking up on them and getting a few fingers under the mouth when they are foraging and quickly yanking them off the rock before they have a chance to do anything.
I've heard though that even if they do clamp down you can pull hard and actually pull the shell off the meat if you have to.
Big rock scallops scare me more than abs. I've had then snap down hard and fast causing some serious pain on my fingers.
The only thing to enter a scallop shell now is my dive knife.
If an 8" rock scallop can cause havoc I can only imaging what a giant clam could do and how strong they would be. I theoretically do believe they could trap a diver drowning them.

 

[Water Boy76]

Can't even count how many friends I've lost to Giant Sea Clams. Somebody should really do something about it.