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Spotted on sonar: a 14-foot symbol of hope for Atlantic sturgeon

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Promising signs have come to light, but any recovery is a long way off for this endangered Hudson River fish. To restore viable populations of these gentle giants, multiple efforts must continue.

 

Atlantic sturgeon had a welcome burst of attention this month as we await their annual migration into the Hudson. Science writer Andrew Revkin delighted readers with a National Geographic report describing a giant 14-foot Atlantic sturgeon observed in the Hudson River during a high-tech survey last June. News of this behemoth gliding just above the sandy bottom near Hyde Park followed reports of more juvenile sturgeon in the Hudson.

Can it be that Atlantic sturgeon are finally showing signs of a rebound?

hope for Atlantic sturgeonThose are certainly positive signs. Still, we remain hopeful but cautious, because these fish are still classified as endangered and remain a long way off from recovery.

Sturgeon populations coastwide are barely a hint of the bountiful populations that existed prior to the late 1800s. They have been harvested to the brink of extinction in the Hudson and the coastal Atlantic.

The Atlantic States Marine Fisheries Commission and the state agencies that collectively manage Atlantic sturgeon have been engaged in efforts to protect and restore viable populations of these fish coastwide. This species has managed to survive since the age of the dinosaurs. But because sturgeon eggs are “caviar,” the harvest pressure on Atlantic and other species of sturgeon was devastating. Now, with their numbers so low, and because females don’t reproduce until around the age of 20, any recovery will happen slowly for Atlantic sturgeon.

To restore viable sturgeon populations and to ensure the long-term survival of the species, we’ll need to continue multiple efforts currently being undertaken by fishery managers along the coast: 1) identify and protect spawning habitat, like the Hudson, 2) reduce or eliminate “bycatch” in the ocean, 3) determine patterns of migration, 4) remove barriers to reconnect and re-establish ancestral spawning habitat, 5) enforce harvest restrictions, 6) reduce mortality in all life stages, and 7) continue scientific study that will add to the body of knowledge surrounding Atlantic sturgeon and the efforts to revitalize their populations.

What makes the sighting of a large sturgeon cause for excitement is that sturgeon are slow growing and late maturing fish. For a sturgeon to grow to such a large size, it must run a gauntlet of potential threats. Sturgeon take nearly two decades to reach sexual maturity, and continue to grow throughout their lives, albeit more slowly as they get older. Atlantic sturgeon can live to be 60 years old. Females produce an number of eggs to ensure the renewal of the species: Young sturgeon have only a remote chance of avoiding predators and surviving until sexual maturity many years later.

sturgeonDespite their primitive appearance, these fish are perfectly adapted to thrive in the deep, dark, murky waters of the Hudson. Using four tactile chin barbels extending down from the underside of their snout, and rows of “electroreceptors,” able to detect weak electric fields in the water, sturgeon can forage in the muddy substrates without the need for eyesight.

The “Black Gold Rush” for caviar in the late 1800s and 1900s spelled disaster for Atlantic sturgeon. The largest, most prolific females were targeted for their eggs, which led to a precipitous decline of the species.

At the same time, Atlantic sturgeon were being further harmed by ship strikes, dams blocking their spawning grounds, pollution, and other forms of habitat degradation. They were, and still are, entangled in nets set for other species, caught up as “bycatch.”

Collectively, these various forms of human induced mortality have led to a coastwide collapse. Sixteen of 38 spawning runs on coastal rivers have been eliminated.

To prevent the complete loss of the species, in 2012 Atlantic sturgeon were placed on the Federal endangered species list. Possession of both Atlantic and shortnose sturgeon is prohibited, and sightings of dead sturgeon should be reported to DEC.

It must also be noted that during the construction of the Gov. Mario M. Cuomo Bridge, a significant number of sturgeon were killed, apparently from being struck by the propellers of work boats.

DEC biologists

Amanda and her crew of DEC biologists bring an Atlantic sturgeon alongside the boat for tagging and collection of scientific data under Federal permit NMFS-20340 (Photos: George Jackman / Riverkeeper)

The New York State Department of Environmental Conservation has a team of dedicated scientists who specifically work to monitor the various life stages of these gentle giants and their movements within the river. Monitoring by the DEC is led by senior biologist Amanda Higgs, who has been researching these fish for more than a decade.

Amanda and her team of dedicated professionals are on the river in all weather to monitor both the juveniles and the adult life stages of sturgeon. She and her team, operating under Federal permit (NMFS-20340) in conjunction with Dr. DeWayne Fox from Delaware State University and Dr. John Madsen from the University of Delaware, attach acoustic tags to adult sturgeon, while also taking DNA samples and using other sophisticated research techniques to effectively monitor populations and track their movements to help ensure the long-term survivability of these fish.

What is so surprising about a 14-foot sturgeon being sighted in the Hudson River is not that this magnificent fish can grow to such lengths. It’s that this particular fish has beaten the odds for so long in spite of natural and human threats. At the hand of man, Atlantic sturgeon have been brought to the edge of extinction. We continue to hope that at the hand of man, Atlantic sturgeon populations will one day recover.