Species has a combination of problems such as overfishing, high bycatch, and poor management.
Scallop, Peruvian Calico

The Peruvian Calico Scallop is a fast growing and short-lived marine bivalve, found in shallow waters. Peruvian Calico Scallop abundance and landings are highly variable and correlated to El Nino Southern Oscillations cycles (ENSO). In southern Peru, abundance and catches increase greatly during ENSO events and then subsequently decline to low levels, whereas in northern Peru the opposite occurs.

In the past, fishing for the Peruvian Calico Scallop was primarily concentrated to a large bay in southern Peru, but this population is now depleted. In recent years fishing effort has moved to northern Peru, where populations appear to be increasing as a result of restocking efforts in these bays. Few management regulations are in place for this fishery and enforcement of regulations is poor so there is nothing to prevent overfishing.

Scallops are hand-collected by divers, so fishing results in minimal habitat impacts and virtually no bycatch.

Full species report here.