One Tiny Fish’s Struggle for Survival

The most important fish in the sea is facing an uphill battle for survival.

The Atlantic menhaden—a type of herring—is highly sought after by both fish and fisherman. Menhaden, also known as “bunker” or “pogy” to many anglers, is being fished at unsustainable rates and its population has plunged down below 10 percent of historic levels.

RSMAS Marine Biology & Fisheries Professor Jerry Ault is worried about these little plankton-eating fish and the ripple effect their dwindling numbers could send through the entire U.S. Atlantic coast marine ecosystem.

The coastal migration of menhaden schools intersects with the movements—and stomachs—of many larger and more highly valued predators. In Florida, the “Silver King” (Atlantic tarpon), king mackerel, sharks, cobia, and birds like brown pelicans, bald eagles, and ospreys, as well as Royal and Sandwich terns all rely upon these tiny fish to fuel their migrations.

“Wherever they travel, Atlantic menhaden feed on plankton, converting it into fatty, high-nutrient tissue that larger fish then readily consume to fuel their own migrations,” Ault explains. “All of these larger fish need the rich menhaden flesh for sustenance and reproductive power.”

In Chesapeake Bay, they are the primary diet for striped bass, bluefish and weakfish. As they head south for the winter, they cross paths with Atlantic tarpon off the Florida coast. When they head north again in late spring and summer, as far as the waters off Cape Cod, they become prey to bluefin tuna as well as many other ocean giants.

“If allowed to continue unchecked, the unsustainable fishing of menhaden could create a domino effect that cascades throughout east coast fisheries, potentially forcing the collapse of not only this fishery, but also other economically critical fisheries,” says Ault.

More of these tiny fish are caught per ton than any other fish on the East Coast, all for their rich, nutritious meat. Hundreds of millions of menhaden are hauled in annually, ground up, and reduced to fish meal and oil for human dietary supplements, such as like omega-3 fatty acid pills or processed into pet foods, fertilizers, and feed for agricultural animals, as well as farm-raised fish.

During a critical meeting in November, Ault urged the Atlantic States Marine Fisheries Commission (ASMFC), the inter-governmental body that manages the fishery and sets fishing levels, to support the science to better protect the small but mighty fish that plays a vital role in keeping our oceans healthy.

In an overwhelming vote of 14 to 3, the commission took the first step by agreeing to reduce harvest of Atlantic menhaden by 37 percent compared to 2010 levels.

“The action by the commission sets limits on the fishery and with the new reference points they adopted over the next few years the amount of menhaden left in the ocean will quadruple,” said Ault.

Watch this video to learn more about Ault’s fisheries research in the Dry Tortugas.

Annie Reisewitz
Follow Annie on Twitter @annelore

Oyster stuffing and other Thanksgiving traditions

When you think of Thanksgiving dinner does turkey and green bean casserole or oysters and shrimp cocktail come to mind? What you may not realize is that early celebrations to give thanks for a bountiful harvest included oysters and seafood among its traditional dishes. Today, oyster stuffing, shrimp cocktail, crab and even smoked fish dip still have a place alongside (or inside) the traditional turkey and green beans on many dinner tables.

If your Thanksgiving menu includes seafood this year, choose sustainably.  There are several free sustainable seafood guides that can become your personal shopping assistant. The most popular, Monterey Bay’s Seafood Watch Guide, is available as a smart phone app as is the Blue Ocean Institute’s FishPhone. Another reference guide is NOAA’s FishWatch Facts, which also provides information on the national standards that goes into sustainable seafood assessments.

What determines a fish’s sustainability is a complex formula that takes into account, among other things, current fish population levels and how effective management measures are in preventing overfishing and population declines. This assessment starts with good science.

Lucky for us, much of this good science is being done here at RSMAS. There are many RSMAS scientists working to collect the fishery population data and management that can be used to determine sustainability assessments.

If you want to learn more about how the science collection process works, check out the research being done by Dr. Jerry Ault and team in the Fisheries Ecosystem Modeling and Assessment Research (FEMAR) group and researchers studying fishery management, fish population dynamics and aquaculture.

What is your favorite Thanksgiving dish?

– Annie Reisewitz

Follow Annie on Twitter @annelore