Fish underwater around rocks and boats

[ScubaPaladin]

I have a question...

Is there any scientific reason why fish tend to congregate enmasse near wrecks and also by rocks or openings underwater? I am providing a writing sample for a job and this is something I was going to incorporate within my writing sample short story.

If anyone knows, I would appreciate any assistance.

 

[Mike Nebel]

food

 

[miketsp]

Just to expound on the 1 word answer above.
Invertebrates, such as mussels, sponges, scallops and sea fans, attach themselves to hard substrates. These organisms then support higher levels of the food web & fish populations congregate and propagate around them. Plus many fish are designed (coloured/patterned) to merge in with irregular backgrounds. Holes and niches will provide physical protection from predators.

 

[dive_lover88]

they are waiting for free food esp during choopy seas, where new divers or those who get seasick easily usually upheave their food to feed the fishes gathered around the boat

 

[Machiavelli]

I would also add that congregation en masse tends to dilute one's chances of being eaten and that congregating around any kind of cover (reefs, wrecks, rocks) is generally safer than open water.

 

[ScubaPaladin]

Thanks. I really appreciate everyone's input.