Why we need to put the fish back into fisheries

Space Daily via SPX: Overfishing has reduced fish populations and biodiversity across much of the world's oceans. In response, fisheries are increasingly reliant on a handful of highly valuable shellfish. However, new research by the University of York shows this approach to be extremely risky.

The research, published in the journal Fish and Fisheries, shows that traditional fisheries targeting large predators such as cod and haddock, have declined over the past hundred years. In their place, catches of shellfish such as prawns, scallops and lobsters have rocketed as they begin to thrive in unnaturally predator-low environments often degraded by the passage of trawls and dredges.

In many places, including the UK, shellfish are now the most valuable marine resource. The research by the Environment

Department at York suggests that although a shellfish-dominated ecosystem appears beneficial from an economic perspective, it is highly risky. Like simplified agricultural systems, these shellfisheries are unstable in the long-term and at great risk of collapse from disease, species invasions and climate change.

Warming and acidification of our oceans due to greenhouse gas emissions is expected to affect shellfish worst. Ocean acidification, in particular, will limit the ability of scallops and other shellfish to form proper shells, and lead to widespread mortality....

Shellfish on a beach, shot by Titus Tscharntke, Wikimedia Commons, public domain