"Sturgeon are disappearing from North American rivers where they thrived for millions of years. And the quest to save them is exposing the limits of the Endangered Species Act."
"The American caviar rush began on the lower Delaware estuary, a landscape today crowded with chemical plants, container ports and the sprawl of Philadelphia. But this was the 1870s, when nature edged up to the city’s limits, when probably nowhere else in the country was home to more Atlantic sturgeon: During the spring spawn, an estimated 360,000 adults thronged the reach that marked the brackish threshold between bay and river. Theirs was the roe prized by the Russian czars, whose brokers at one point paid more than $1,400 in today’s dollars for a single female Atlantic sturgeon. Bayside, N.J., came to be known as Caviar, a miniature, pop-up New Bedford in the state’s marshy south. During the fishery’s peak, in 1888, 16,500 Atlantic sturgeon — they can live 60 years and grow to 14 feet and 800 pounds — were “harvested,” or killed. Most were female, and the millions of eggs that each could produce during a spawn never made it into the water within which they were meant to hatch.
For an estimated 10 to 15 million years, Atlantic sturgeon, or Acipenser oxyrinchus oxyrinchus, have spawned in as many as 38 rivers throughout eastern North America. An anadromous fish, it is born in fresh water, spends its adulthood in salt water and returns to its natal rivers to spawn. Because individuals from different rivers do not commonly interbreed, their homing instinct has produced populations whose genetics are unique to the waterways of their birth. But the caviar rush of the late 19th century ravaged the Atlantic sturgeon, and today breeding populations remain in only 22 of its 38 natal rivers. In 2012, the species became protected under the Endangered Species Act.
At the time, researchers estimated that the Delaware population consisted of 300 or fewer spawning adults per year. While the Delaware Atlantic sturgeon is just one branch of the species, its decline epitomizes the global biodiversity crisis. “If you lose one population and their functional genetic diversity, then you’re possibly eliminating the ability for the species to adapt to new conditions in the future,” says Isaac Wirgin, an associate professor of environmental medicine at N.Y.U. Langone Health, who has sequenced Atlantic sturgeon DNA. In other words, when one branch is extirpated, a block from the genetic Jenga tower is removed and the whole family teeters further."
Andrew S. Lewis reports for the New York Times Magazine February 2, 2023.