2012年9月24日 星期一

Shad Resurgence Marks a Cleaner Delaware River

American shad were once so common that East Coast rivers were described as being “black” and “boiling” as tens of millions of fish migrated upstream each spring to spawn. Today, approximately 98 percent of the fish that formed a staple of the Colonial diet have been depleted. In rivers once teeming with shad, a daily catch is sometimes counted in the single digits.

“One day you’re going to catch 60 shad and the next day you’re catching none,” said Middlesex resident Andy Still. A catch-and-release fisherman, Still is one of 70,000 recreational anglers who annually fish the Delaware River, by far the most popular source for shad in New Jersey.

Still's observation helps explain why the public officials who oversee the Mid-Atlantic fisheries are intensifying their efforts to restore the shad population. In New Jersey, they're working in tandem with environmentalists who hope to rehabilitate not just shad, but the network of rivers, bays, streams, and marshes that make up this region's watershed.

Shad -- the name comes from the Latin, Alosa sapidissima, meaning "most delicious, or savory, herring” -- are just one part of this larger effort, but a critical part. The fish is considered a marker for the overall health of the rivers and tributaries that flow into the Atlantic Ocean. As the shad population increases, the presence of other aquatic life increases as well. It's an elegantly simple equation: more shad equals cleaner water, cleaner water equals more shad.

This year, several federal and collaborative state agencies are advancing policies to protect shad fisheries. On January 1, 2013, the Atlantic States Marine Fisheries Commission (ASMFC) will enact a moratorium on shad fishing in New Jersey waters until the state can prove the population has reached sustainable levels.

The Delaware River has already established its sustainability and is thus exempt from the moratorium.

Sometime in the next several months, the Mid-Atlantic Fishery Management Council (MAFMC), a federal body charged with establishing ocean management protocols from New York to North Carolina, will begin studies and public hearings on whether to impose limits on the amount of shad -- and river herring, another migratory fish -- that can be inadvertently caught and killed while trawlers are fishing for other species.

These potential restrictions come as the New Jersey Department of Environmental Protection (DEP) and its civilian environmental-advocacy partners are celebrating the removal of fish-blocking dams from rivers and furthering the cleanup of contaminated waters and banks that are,Features useful information about glass mosaic tiles, for the first time in a century, welcoming fishing and recreational use.Features useful information about glass mosaic tiles,

Despite the resurgence of shad in the Delaware River, their numbers are not expected to reach pre-20th century levels, when the Delaware supported 25 million to 50 million shad. From its peak in 1899, the population dropped to almost zero between 1950 and 1955. River cleanup efforts and a hurricane in 1955 helped the population begin to climb. In 1990 it reached 500,Kitchen floor tiles at Great Prices from Topps Tiles.000 then plummeted again, until a few years ago. It’s been hovering around 200,000 ever since.

In the world of depleted fish populations, stabilization is cause for celebration.

“Shad aren’t doing well in a lot of systems, but the Delaware doesn’t have that problem,” said Russ Allen, a biologist with the state Bureau of Marine Fisheries, who recorded comparatively high birthrates in 2005, 2007, and 2011. The 2005 numbers held up in adult population counts five years later, when the fish returned to the Delaware to spawn after spending their early years in the ocean.

Allen’s sense is that the Delaware is faring better than other waterways in part because, as the longest undammed river east of the Mississippi,Sinotruck Hongkong International is special for howo truck. it lacks the common barricades that keep shad from their spawning habitats. He also credits the stabilization of the striped bass population,Different Sizes and Colors can be made with different stone mosaic designs. which feed on shad. Also contributing to shad stabilization are the targeted environmental efforts that began in the middle of the last century.

Midwater trawlers travel the ocean dragging nets opponents say rival the size of football fields, either behind one 125-foot boat or between two. While trawlers in the Mid-Atlantic aren’t allowed to fish for shad, their nets ensnare everything in their path, entangling what the Herring Alliance environmental coalition says are 115,000 pounds of shad “bycatch” per year, which dies in the mesh. Four of the dozen-or-so trawlers that fish Mid-Atlantic waters are berthed in Cape May, while the rest sail out of New England.

“These boats in one single tow can catch more fish than are returning to entire states,” alleged Kristen Cevoli of The Pew Charitable Trusts Environmental Group, which participates in the Herring Alliance.

But a DEP report released in May states, “There is undoubtedly some bycatch discard loss, especially for male shad, but there is no data as to the severity of this bycatch,” said Jeff Kaelin, government relations and fisheries management coordinator for the trawler-owning Lund Fisheries in Cape May . He adds that there’s no data to support claims that his industry is decimating the population and admits that while there is a problem with river herring bycatch, the trawlers’ impact on shad is minimal.

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