Friday, July 13, 2012

Tracking New Jersey's Atlantic Sturgeon

Acoustic receivers in Delaware Bay track migration patterns of Atlantic sturgeon

New Jersey researchers are netting sturgeon and implanting them with acoustic telemetry tags, and the NJDEP is placing 18 acoustic receivers on the New Jersey side of the Delaware Bay to track their movements. Fishermen in the bay may notice the receivers; they're attached to white buoys marked "NJDEP Research."

The sturgeon family is among the most primitive of the bony fishes. There are shortnose sturgeon and Atlantic sturgeon. The body surface contains rows of bony plates or "scutes" and they are typically large, long-lived fish. They can inhabit a great diversity of habitats from fast-moving freshwater riverine environment downstream and, for some species, into the offshore marine environment of the continental shelf.

Atlantic sturgeon are similar in appearance to shortnose sturgeon (Acipenser brevirostrum), but can be distinguished by their larger size, smaller mouth, different snout shape, and scutes. Atlantic sturgeon have been aged to 60 years.

Understanding their movement in the Delaware Bay is important because Atlantic sturgeon is considered an "anadromous" species. This means the fish spend most of their time in marine waters and estuaries, then migrate into fresh water to spawn. Adults can grow up to 14 feet long, weigh up to 800 pounds.

New Jersey will probably never make a comeback as a producer of caviar from sturgeon, but the Atlantic sturgeon have a chance to return in greater numbers.

Shortnose sturgeon were federally listed in 1967 as an endangered species but in some systems abundance may be increasing to levels that would allow reconsideration of their endangered status. Some locations, such as Saint John River, New Brunswick, Canada, support significant numbers of shortnose sturgeon.

The National Oceanic and Atmospheric Administration (NOAA) announced that New Jersey's Atlantic sturgeon population would be listed as "endangered" under the Federal Endangered Species Act effective April 2012. Currently, NJ has only one other fish species listed as endangered - and it is also a sturgeon, the shortnose sturgeon.

Stock abundance of Atlantic and shortnose sturgeons steadily declined throughout the 20th century as a result of overfishing and habitat destruction. Fisheries for Atlantic sturgeon existed until 1997 when a moratorium was declared from Maine to Florida.

For more information about Atlantic sturgeon and the new tracking project, go to njfishandwildlife.com/news/2012/sturgeon_research.htm or http://www.nmfs.noaa.gov/stories/2012/01/31_atlantic_sturgeon.html

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