Animal rights campaigners are calling for a clampdown on people fishing for crabs in the Mersey.
Many of the crabs are undersized, the foundation said
The Vicky Moore Foundation, based in Southport, has said some of those catching shore crabs in the marina at New Brighton are treating them as toys.
Many of the crabs are returned to the water damaged, while some taken away are undersized according to EU guidelines, the foundation said.
It hopes to start a debate about the ethics of crab fishing in the area.
The crabs are caught by fastening a piece of bacon or other bait on a piece of string and lowering it into the water.
Foundation spokesman Tony Moore said: "I just wanted to start a discussion on it, to get people thinking 'Is it right to do this sort of thing?'
"Should we really be treating these little animals, these creatures who all have a life - and however lonely it seems to us it's their own life and their own world - should we be treating them as toys?"
Edible crabs come under EU minimum size regulations and the foundation said some people could be liable for prosecution if caught by a fisheries officer.
According to Defra, any edible crab shorter than the minimum length, which differs according to fishing area, should be returned to the sea if caught.