Focus on Atlantic Sturgeon in Chesapeake Bay Region
- 85 million years ago: Fossil evidence shows that sturgeon exist at least this early in Earth history.
- Pre-colonial Chesapeake Bay: Sturgeon play an important role in the legends, lore, and lives of Native Americans, who exploit the spring spawning run for food.
- 1607: The Jamestown colonists quickly adopt sturgeon as a food source. Captain John Smith makes numerous references to this plentiful fish.
- 1609: Sturgeon sustain the Jamestown colonists during the “Starving Time.”
- mid-1600s: Attempts to transport sturgeon meat and caviar to England fail. Land clearance and deforestation result in increased runoff of silt, which along with dredging and dam building reduces the amount of available spawning habitat.
- 1700s: A strong prejudice against sturgeon develops. Shad fishermen routinely kill the fish because entangled sturgeon damage their nets. Sturgeon meat and roe are often fed to hogs or used for bait.
- 1860s: First successful fishery for Atlantic sturgeon develops in the Delaware River and Bay.
- 1870s: Sturgeon fishing expands to all major rivers along the Atlantic seaboard as smoked sturgeon and caviar gain acceptance and railroads facilitate transport.
- 1880: The U.S. Fish Commission begins to compile statistical information on commercial fishery landings.
- 1880s: Catch records show a great abundance of Atlantic sturgeon, with an annual catch of 17,700 lbs. from the Rappahannock River, 51,661 lbs. from the York River and its tributaries, and 108,900 lbs. from the James River.
- 1888: Sturgeon landings from Atlantic and Gulf coast states reach a peak of more than 7 million pounds
- 1890s: Sturgeon catch drops precipitously
- 1901: Annual coast-wide harvest declines to 650,000 pounds
- 1908: Sturgeon landings from Atlantic and Gulf coast states reach only 2.2% of 1888 peak.
- 1920: The catch of Atlantic sturgeon from all of Chesapeake Bay amounts to only 22,888 pounds; the fish is considered scarce.
- 1928: Virginia enacts a law asserting that “no sturgeon less than 4-feet long may be removed from the waters of the State."
- 1930s-40s: The Chesapeake Bay Atlantic sturgeon fishery continues, but at a fraction of its previous rates.
- 1950s: Decline in Chesapeake Bay water quality accelerates as post-war boom in population, fertilizer use, and sewage discharge delivers massive nutrient loads to the Bay. Consequent increase in silt and low-oxygen conditions further reduces nursery habitat for Atlantic sturgeon in the Bay.
- 1956: Records indicate a catch of 23,000 lbs. from Chesapeake Bay
- 1974: Continued decline in Atlantic sturgeon prompts Virginia to impose a total moratorium on Atlantic sturgeon catches in state waters.
- 1990: Atlantic States Marine Fisheries Commission (ASMFC) enacts a Fishery Management Plan for Atlantic sturgeon that calls for rebuilding of the coast-wide stock.
- mid-1990s: Many scientists conclude that Atlantic sturgeon are locally extinct (extirpated) in Chesapeake Bay
- 1998: NMFS concludes that spawning populations appear to be extirpated from all Maryland tributaries of the Bay and the Rappahannock River, Virginia. ASMFC amends 1990 plan to include a stock-rebuilding target of at least 20 protected year classes of females in each spawning stock, to be achieved by imposing a coast-wide harvest moratorium.
- 1999: NOAA Fisheries Service prohibits the take of Atlantic sturgeon from the nation’s Exclusive Economic Zone (EEZ)
- 2003: The National Marine Fish Service (NMFS) and the U. S. Fish and Wildlife Service (USFWS) hold a workshop to review the status of Atlantic sturgeon; participants conclude that some populations seem to be recovering while other populations continue to be depressed.
- 2005: VIMS delivers report on “Essential Fish Habitat of Atlantic Sturgeon in the Southern Chesapeake Bay” to NOAA’s National Marine Fisheries Service. NMFS initiates a second status review of Atlantic sturgeon.
- 2007: A team of scientists from NOAA, the U.S. Geological Survey, and the U.S. Fish and Wildlife Service completes its Status Review, identifying 5 “distinct population segments” (Gulf of Maine, New York Bight, Chesapeake Bay, Carolina, and South Atlantic) to be considered for possible listing under the Endangered Species Act.
- mid-2000s: Occasional occurrences of young-of-the-year sturgeon in the James and York Rivers, and collection of 150+ reproductively active adults in the upper James, suggest strongly that spawning still occurs in these rivers.
- 2009: The Natural Resources Defense Council (NRDC) petitions NMFS to consider the 5 distinct population segments of Atlantic sturgeon for listing under the Endangered Species Act.
- 2010: The James River Association, partnering with Virginia Commonwealth University and Luck Stone, constructs an artificial spawning reef for sturgeon in the James River.
- 2012: In response to the NRDC petition, NMFS lists the Chesapeake Bay, New York Bight, Carolina, and South Atlantic populations as endangered, and the Gulf of Maine population as threatened. NOAA lists the Chesapeake Bay population of Atlantic sturgeon as endangered
- 2008: VCU scientists begin to observe growing numbers of sub-adult and adult sturgeon in Chesapeake Bay tributaries, particularly the James River, although this population remains severely depleted from historical levels.
- 2013: ASMFC initiates a stock assessment for Atlantic sturgeon. The Virginia Institute of Marine Science (VIMS) initiates a tagging program in collaboration with state agencies, NOAA Fisheries, U.S. Fish and Wildlife, and the U.S. Navy. The goal of the 3-year, NOAA-funded partnership is to improve understanding of habitat use by both sub-adult and juvenile Atlantic sturgeon within Chesapeake Bay.
Sturgeon are an ancient group of fishes whose fossil record dates back at least 85 million years, to the time of the dinosaurs. But in just the past few hundred years, overfishing and habitat destruction have devastated sturgeon populations worldwide, with 16 of the 27 existing species of these "living fossils" listed as critically endangered by the International Union for the Conservation of Nature.
A "Triple Whammy"
Atlantic sturgeon—an anadromous species that resides in the ocean but enters freshwater rivers to spawn—have suffered from a "triple whammy."
First, VIMS research shows that sturgeon historically preferred to lay their eggs just below the fall line—the upstream extent of navigation on local rivers. Unfortunately for these fish, that's exactly where we have built a string of major cities—including Richmond on the James River and Washington, D.C. on the Potomac. "So these fish naturally spawn where there's been a lot of habitat degradation," says Musick.
Second, the widespread deforestation that accompanied the shift to European-style agriculture fed vast quantities of silt into Virginia's previously clear tidal rivers. "Sturgeon prefer to lay their eggs on gravel banks," says Musick. "Clearing of forests for farming caused many of these banks to silt over." There was also a major effort in the 1830s to remove the banks from the river to enable shipping.
Last, sturgeon suffer from their low reproductive potential: females don't reach sexual maturity until they're around 12 years old, and they only spawn every 2 to 6 years. "These demographics make sturgeon very vulnerable to over-fishing and stock collapse," says Musick. "Sturgeon were overfished and virtually clear-cut by fisheries in the last two decades of the 19th century, and have not been able to recover since."
Research for Recovery
VIMS researchers continue to collaborate with other state and federal scientists, as well as local citizens' groups and commercial anglers, to overcome the challenges to sturgeon recovery.
Hager began his research by partnering with local commercial fishermen, the US Fish and Wildlife Service (USFWS), and the Army Corp of Engineers' Engineer Research and Development Center. They used acoustic tracking technology to throw light on sturgeon abundance, habitat use, behavior, and seasonal movements within local waterways. They also studied numerous parameters related to sturgeon bycatch in Virginia's gill-net fisheries. These efforts led to development of gillnets that reduce the retention of sturgeon but maintain catch rates of targeted species. Research projects were funded in collaboration with fishermen through the Fisheries Resource Grant administered by Virginia Sea Grant's Marine Advisory Services Program. He partnered on these studies with Matt Balazik, a graduate student at Virginia Commonwealth University, Chuck Frederickson of the James River Association, and Albert Spells of the USFWS.
Musick has collaborated with Hager, his graduate students, technician Tara Bushnoe, and Dr. Donna Bilkovic in VIMS' Center for Coastal Resources Management to locate and map the gravel beds that sturgeon prefer for their spawning and nursery grounds. Because many of these beds are now buried by silt, their efforts required use of side-scan sonar to peer beneath the seafloor. This effort was funded largely by USFWS and the NOAA Chesapeake Bay Office.
Hilton provides the broad expertise of sturgeon biology that is needed to help identify unique aspects of East Coast Atlantic sturgeon stocks. The morphological, genetic, and behavioral structure of Atlantic sturgeon, and sturgeon species generally, are unclear and hotly debated. Atlantic sturgeon are highly migratory, and this type of information is key to ongoing efforts for sturgeon restoration.
These VIMS' studies laid the groundwork for a 2010 milestone in sturgeon restoration—a plan by the James River Association, partnering with Virginia Commonwealth University and Luck Stone, to construct an artificial spawning reef for sturgeon in the James River.
This project—given the green light by the Virginia Marine Resources Commission in January 2010—used large chunks of granite to build an artificial spawning reef at the Turkey Island Cutoff, near the Presquile National Wildlife Refuge. The 70 X 300-foot reef rises 2-feet above the muddy bottom, hopefully giving the few remaining sturgeon a fighting chance at reproduction. Researchers with the Virginia Sturgeon Restoration Partnership are now monitoring the success of this structure. All involved hope that some of the fish that use it will be spawning females.
In 1990, a 20-40 year moratorium on all Atlantic sturgeon fisheries was issued by ASMFC. NOAA Fisheries Service then closed the Exclusive Economic Zone (EEZ) to Atlantic sturgeon take in 1999. Following these actions and a workshop held in 2003 on Atlantic sturgeon, NOAA Fisheries Service initiated a second review of the status of Atlantic sturgeon. In 2007, A Status Review Team (SRT) consisting of Federal biologists from NOAA Fisheries Service, U.S. Geological Survey (USGS) and U.S. Fish and Wildlife Service (FWS) completed a Status Review of Atlantic sturgeon (Status Review for Atlantic Sturgeon (Acipenser oxyrinchus oxyrinchus) in the United States.
85 MYA: Fossil evidence shows that sturgeon