Most of the time, fishermen fish for one particular creature--be it tuna, sardines, or shrimp. Unfortunately, species tend to exist in a commingled muddle called ecology, and it's often difficult to separate them with fishing gear.

On the east coast of the US, longfin squid are caught with trawl nets. When dragged through the water, trawl nets also collects things which are not squid, called bycatch. And although the population of longfin squid seems to be reasonably healthy, some of these bycatch species are not doing so well.

River herring is one of these unfortunates. Back in October, New Jersey was trying to figure out how to let fishermen keep catching squid without killing river herring, but the state had no money for implementing any proposed solution.

Now, with the river herring situation growing more dire and a continued lack of funds for studying it, they've been forced to ban the catch and sale of river herring in New Jersey.

The ban only affects state waters, so squid fishermen who trawl in federal waters won't be in trouble if their nets keep bringing up river herring. But these fish can't be brought back to New Jersey and sold. (Although bycatch species aren't caught intentionally, fishermen are usually happy to sell them, rather than throwing them back into the water. I'm pretty sure that the river herring are already dead by the time they're brought up and sorted out from the squid, so it doesn't matter to them.)

Anyway, the upshot is that the new ban doesn't help the bycatch problem. Other things might. 

Someday, river herring could benefit from studies on butterfish, another longfin squid bycatch species.  Researchers have produced models that predict, in real time and on a fine geographic scale, exactly where butterfish are. They hope that these models can help squid fishermen avoid butterfish while still catching squid.

I wonder if the river herring folk are already talking to the butterfish folk?

(Of course, it's all one to the squid.)