As the summer heats up along Atlantic coast, coastal residents and visitors alike head out in boats, stake out spots on docks and bridges, or don rubber waders and forge into the waves along a beach’s breakwater. Each is armed with a long pole and a zeal for the chase. Their quarry is the striped bass, a silvery fish with trademark dark stripes running the length of its body from head to tail. The striped bass, or striper, is an anadromous fish native to the Atlantic coast of North America, and usually grows to around three and half feet. The historic abundance of the striped bass, as well as its ideal size for recreational fishing, makes it a highly valued sport fishing species. In 2004, recreational fishermen landed more than 2.5 million stripers.
Unfortunately, recent evidence indicates that this time-honored recreational fishery may be in danger of collapse. Recreational fishermen in Massachusetts reported a staggering 85% drop in striper numbers between 2006 and 2011, and Massachusetts is not alone: states up and down the coast are seeing fewer stripers, and the schools of bass that migrate up the coast from the Chesapeake Bay to Maine are thinning out. More and more fishermen are heading home empty-handed at the end of the day, and more importantly, the disappearance of the striped bass leaves a lack of an important member of the marine ecosystem and food web.
Many factors are responsible for the decline of the striper, but one is often overlooked: food. Small forage fish, including Atlantic herring and river herring, compose around 90% of the striped bass diet, and these forage fish face the pressure of a significant fishery of their own. While ignored by recreational fishermen, Atlantic herring are heavily fished by commercial fishermen, largely for use as bait in the lobster industry. In 2011, for instance, U.S. commercial fishermen harvested over 174.3 million pounds of Atlantic herring.
Recent assessments indicate that Atlantic herring are not overfished, but surveys of population levels and safe catch limits rarely take proper account of the amount of a forage fish required to feed its predator species. As a result, after the herring fishery has hauled in its 170 million pounds of fish, there may not be enough herring left to both maintain a steady herring population and provide the striped bass with sufficient prey.
River herring, meanwhile, have been depleted by years of overfishing and habitat loss due to dams. Total landings of commercially fished river herring have decreased steeply over the years: in the 1950s, over 60 million pounds of river herring were harvested by commercial fisheries throughout the US, but this number had decreased to around 2 million pounds by 2012. In response to this decline, many states have implemented moratoriums on intentional catch of river herring and have made strong efforts to remove dams and restore upstream habitat; river herring runs in many New England rivers seem to be on the rebound. But river herring are still at risk at sea, where they are caught as bycatch by the Atlantic herring and mackerel fisheries.
This scarcity of prey spells danger for the striped bass. Without sufficient forage fish, there will be fewer striped bass in the sea, and more fishermen with empty hooks.