Acipenseridae: Sturgeon Family, Species and Caviar

Acipenseridae is the scientific name of the sturgeon family: large, long-lived, bottom-feeding fish of the Northern Hemisphere, and the source of true caviar. Wikipedia counts 27 species in five genera; the Animal Diversity Web (University of Michigan) gives 23. The difference reflects how many populations each source treats as separate species, not a change in the fish.

Sturgeons and paddlefishes are the only two living families of the order Acipenseriformes. They sit in the subclass Chondrostei, an old lineage separate from the teleosts, the group that includes most modern fish (Wikipedia). The oldest sturgeon fossils, a partial skull, are about 100 to 94 million years old.

Most species are anadromous: they live in river deltas, estuaries or the sea and swim upriver to spawn (Wikipedia). The Animal Diversity Web notes that others live in freshwater lakes and rivers.

A sturgeon is easy to place at family level once you know the marks:

• Scutes: five lengthwise rows of bony plates along the back and sides instead of ordinary scales (Wikipedia)
• Barbels: four sensory barbels in a row in front of the mouth (Wikipedia, ADW)
• Mouth: on the underside of the head (ADW), suited to feeding on the bottom

Species are harder. In North America, Wikipedia lists the white, lake, Atlantic, green, shortnose and pallid sturgeons; Photograph the whole fish from the side and the head from below, and the app identifies the likely species.

Very. Wikipedia states that over 85% of sturgeon species are at risk of extinction, making them more threatened than any other animal group, and the Animal Diversity Web says all sturgeon species are threatened or endangered. The reason is the same everywhere: demand for meat and roe, combined with a life history that cannot absorb heavy fishing. Sturgeons live 50 to 60 years and do not mature until 15 to 20 (Wikipedia).

Recovery is possible but slow. Wikipedia reports that the Adriatic sturgeon, presumed extinct in the wild from 2011, was reassessed as critically endangered in 2022.

In US waters, NOAA Fisheries lists all five US distinct population segments of Atlantic sturgeon as endangered or threatened since 2012 (Gulf of Maine threatened; New York Bight, Chesapeake Bay, Carolina and South Atlantic endangered). NOAA states it is illegal to fish for, catch or keep Atlantic, shortnose or Gulf sturgeon, and that Atlantic sturgeon can reach 14 feet and 60 years.

Traditionally, yes; not always today. Wikipedia's caviar article says commercial production historically meant stunning the fish and removing the ovaries. Newer methods take the eggs through a small incision, or by stripping along the urogenital muscle, which lets the female survive and produce roe again; the article notes that massage-based removal may give higher quality and a more sustainable supply.

Regulation has pushed production onto farms. According to the same article:

• In September 2005 the US Fish and Wildlife Service banned imports of Caspian Sea beluga caviar, and a month later extended the ban to beluga caviar from the whole Black Sea basin
• In January 2006 CITES supported an international embargo on caviar exports
• A ban on sturgeon fishing in the Caspian made aquaculture the main commercial source
• In 2017 China led production at 100 tonnes, followed by Russia (49), Italy (43) and France (37)

Sturgeon flesh is eaten as well as the roe. Wikipedia says sturgeon are harvested mainly for caviar but also for meat, and that Atlantic sturgeon were once so plentiful in the Hudson River that they were nicknamed "Albany beef". Today most sturgeon meat on sale comes from farms; wild Atlantic, shortnose and Gulf sturgeon may not be kept in the US at all (NOAA Fisheries), and other species are regulated state by state.

Sturgeon is not a salmon. Salmon are teleosts; sturgeons belong to the much older subclass Chondrostei with the paddlefishes (Wikipedia). The two share the habit of running up rivers to spawn, which is where the confusion usually starts.

If you catch a sturgeon by accident, NOAA asks anglers to release it with care, and to report injured or dead sturgeon on (978) 281-9328 in the Greater Atlantic region or (844) 788-7491 in the Southeast.