Endangered sturgeon native to Russia and China obtains endangered species protection in United States
Fish struggle to recover from low populations, in part because they take so long to mature. Males need 12 years before they can reproduce. Females don’t start producing eggs until they are 9 years old, but it can sometimes take up to 14 years.
“This long time to maturity may slow the recovery of the species after a disturbance, compared to that of species with shorter generation times,” the service said.
The Amur sturgeon is a huge fish, with mature adults reaching 10 feet in length. They also have a long lifespan if allowed to run their natural course, with some adult fish reaching 60 years of age.
Sturgeon often migrate upstream to spawn, and unlike other species, conditions in the Amur River, including dams and water quality, are not considered the main threats to the decline of the species or obstacles to its recovery.
The Amur River is the tenth longest in the world, starting in the western part of northeastern China and flowing east, forming the border between Russia and China. The river is believed to contain at least 123 species of fish.
The sturgeon is reputed to be the largest. Female river sturgeons can lay up to 1.3 million eggs, although it is more common for them to lay between 190,000 and 300,000. Once hatched, the survival rate of the young is about about 1 in 2,000 and there is up to 90% attrition for young people. They feed on insects, crustaceans and other fish found in the river.
“A series of Amur Sturgeon surveys conducted between 2005 and 2011 constitute the most comprehensive quantitative assessment of the species known to us, for contemporary or historical population estimates,” the service said. “A decline of more than 95 percent in the abundance of the species was estimated between 1960 and 2010.”
The species is currently listed as Critically Endangered on the Red List of the International Union for the Conservation of Nature.
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