Clam/oyster question

[KING KONG]

So I seen a green colour oyester/clam attached to the rock and surprisingly it is moving! Yesterday it gone under the sand so what should I do? Sorry I am unable to get pics as it everytime hides. It suddenly disappears. It was attached with a rock and suddenly came to life.
I am searching for it with the rod, if I find it,will post a pic. I hv also read that rod can break it in 2 halves,is it right?
I don't know what is it(clam or oyester) till now. It had mouth, it is small and is moving

 

[Rtaylor]

So I seen a green colour oyester/clam attached to the rock and surprisingly it is moving! Yesterday it gone under the sand so what should I do? Sorry I am unable to get pics as it everytime hides. It suddenly disappears. It was attached with a rock and suddenly came to life.
I am searching for it with the rod, if I find it,will post a pic. I hv also read that rod can break it in 2 halves,is it right?
I don't know what is it(clam or oyester) till now. It had mouth, it is small and is moving

Just let it be. That’s normal behavior for a clam/oyster.