Atlantic Sturgeon Receive Endangered Species Status
On February 6, 2012 the National Marine Fisheries Service issued a ruling that granted Atlantic sturgeon endangered status. Atlantic sturgeon are known to live more than 60 years and grow to 14 feet in length. There are five distinct population segments (DPS) of Atlantic sturgeon, each of which have received Endangered Species Act protections. Atlantic sturgeon of the Delaware River, which are part of the New York Bight DPS, have been listed as "endangered," along with those in the Chesapeake Bay, Carolina and South Atlantic DPSs. The Gulf of Maine DPS has received a "threatened" status.
In the late nineteenth and early twentieth centuries, Atlantic sturgeon were a popular source of caviar. Prompted by overfishing, Atlantic sturgeon populations collapsed at the turn of the twentieth century. (Collapse is defined as a 90% decline in the known historic fish population.)
Even though their population collapsed, harvesting of Atlantic sturgeon continued until the Atlantic States Marine Fisheries Commission issued a moratorium in state waters (up to 3 miles from shore) in 1998, and the Atlantic Coastal Fisheries Cooperative Management Act enacted a moratorium in federal waters (beyond 3 miles from shore) in 1999.
Despite these restrictions on fishing, Atlantic sturgeon populations have not rebounded. In 2007 the National Marine Fisheries Service published a "Status Review of Atlantic Sturgeon" for consideration of the protections of the Endangered Species Act. Extensive environmental review, petitions from numerous environmental organizations, and public testimony of the importance of granting Endangered Species Act protection have informed the National Marine Fisheries Service's decision.
On Saturday, February 4th 2012 The Society for the Natural History of Delaware, in a program co-sponsored by the Sierra Club, invited Delaware State University professor of fisheries Dr. Dewayne Fox and his student Matthew Breece to talk about the fisheries science of this valued Delaware fish. These biologists described how Atlantic sturgeon populations continue to be threatened in the Delaware River by a variety of dangers:
- Bycatch in commercial fisheries: Atlantic sturgeon inhabit the same regions as active commercial fisheries (including monkfish) and are caught in commercial fishing nets.
- Vessel strikes: Atlantic sturgeon's natural habitat includes river channels, which are also used by commercial vessels. This leads to sturgeon being struck by ships, and even cleaved in half by ship propellers. Recently there have been 25 documented Atlantic sturgeon moralities each year in the Delaware River, and 62% of these have been from vessel strikes.
- Power plant entrainment: young sturgeon are sometimes caught and die in the intakes for power plant cooling systems.
- Dredging: the spawning habitat of sturgeon is the same region of the Delaware River where dredging operations are taking place. Destruction of this habitat threatens their ability to reproduce and their young to survive.
- Deepening the Delaware River: in addition to blasting and damaging the sturgeon's habitat, deepening will change the hydrological dynamics of the Delaware River, preventing fresh water from pushing the salt-line below the Atlantic sturgeon's spawning grounds in dry seasons. Atlantic sturgeon require fresh water to spawn, and their young cannot survive in salt water. Deepening poses a direct threat to the sturgeon's critical habitat.
- Beach replenishment: Atlantic sturgeon forage in the benthic regions of coastal waters that are used for beach replenishment. These fish are directly killed during beach replenishment activities, and are indirectly harmed through the destruction of their forage habitat.
- Invasive species: introduced invasive species, including flat-head catfish which are native to the Mississippi River, are suspected of eating sturgeon young.
In regions other than in the Delaware River, Atlantic sturgeon are threatened by hydroelectric dams that restrict their access to their spawning habitat (especially the Susquehanna River, which is blocked by the Conowingo Dam a mere ten miles from its mouth at the Chesapeake Bay).
While the policy implications of the Endangered Species Act listing for Atlantic sturgeon in the Delaware River are forthcoming, commercial fishing practices, shipping vessel speeds, power plant water intakes, dredging practices, the ongoing Army Corps of Engineers deepening plans, beach replenishment and invasive species management will have to be considered.
For more information on the new Endangered Species Act ruling for Atlantic sturgeon, visit the National Oceanic and Atmospheric Administration's Office of Protected Resources website (click here).