Paddlefish in the context of "Louisiana"

Caviar or caviare is a food consisting of salt-cured roe of the family Acipenseridae. Caviar is considered a delicacy and is eaten as a garnish or spread. Traditionally, the term caviar refers only to roe from wild sturgeon in the Caspian Sea and Black Sea (beluga, ossetra and sevruga caviars). The term caviar can also describe the roe of other species of sturgeon or other fish such as paddlefish, salmon, steelhead, trout, lumpfish, whitefish, or carp.

The roe can be fresh (non-pasteurized) or pasteurized, which reduces its culinary and economic value.

Sturgeon is the common name for the 27 species of fish belonging to the family Acipenseridae. The earliest sturgeon fossils date to the Late Cretaceous, and are descended from other, earlier acipenseriform fish, which date back to the Early Jurassic period, some 174 to 201 million years ago. They are one of two living families of the Acipenseriformes alongside paddlefish (Polyodontidae). The family is grouped into five genera: Acipenser, Huso, Scaphirhynchus, Sinosturio, and Pseudoscaphirhynchus. Two species (H. naccarii and S. dabryanus) may be extinct in the wild, and one (P. fedtschenkoi) may be entirely extinct. Sturgeons are native to subtropical, temperate and sub-Arctic rivers, lakes and coastlines of Eurasia and North America. A Maastrichtian-age fossil found in Morocco shows that they also once lived in northern Africa during the Cretaceous.

Sturgeons are long-lived, late-maturing fishes with distinctive characteristics, such as a heterocercal caudal fin similar to those of sharks, and an elongated, spindle-like body that is smooth-skinned, scaleless, and armored with five lateral rows of bony plates called scutes. Several species can grow quite large, typically ranging 2–3.5 m (7–12 ft) in length. The largest sturgeon on record was a beluga female captured in the Volga Delta in 1827, measuring 7.2 m (23 ft 7 in) long and weighing 1,571 kg (3,463 lb). Most sturgeons are anadromous bottom-feeders, migrating upstream to spawn but spending most of their lives feeding in river deltas and estuaries. Some species inhabit freshwater environments exclusively, while others primarily inhabit marine environments near coastal areas, and are known to venture into open ocean.

Snagging, also known as snag fishing, snatching, snatch fishing, jagging (Australia and New Zealand), or foul hooking, is a fishing technique for catching fish that uses sharp grappling hooks tethered to a fishing line to externally impale (i.e. "snag") into the flesh of the fish, without needing the fish to swallow any hook with its mouth like in angling. This is achieved by suddenly and vigorously pulling the line (either by handlining or with a rod) when movement is felt, causing the snag hook to "claw" into and grapple any nearby fish like a gaff. Weighted multi-hook rigs can be used to increase chances of success, and modern technologies such as underwater video camera can also be used to visually aid and time the snagging.

Some herbivorous/algaevorous fish species, such as paddlefish, are not attracted to normal angling baits or lures as they primarily filter-feed on plankton. While these fish can be caught using nets, spears or pole hooks, snagging is also used as a less strenuous and more versatile technique. There are also some species of salmon that can be legally harvested by snagging, and are targeted as they migrate upstream to spawn, making them easier to target, and at a time when the fish are at the end of their life cycle.

The American paddlefish (Polyodon spathula), also known as a Mississippi paddlefish, spoon-billed cat, or spoonbill, is a species of ray-finned fish. It is the last living species of paddlefish (Polyodontidae). This family is most closely related to the sturgeons; together they make up the order Acipenseriformes, which are one of the most basal living groups of ray-finned fish. Fossil records of other paddlefish species date back 125 million years to the Early Cretaceous, with records of Polyodon extending back 65 million years to the early Paleocene. The American paddlefish is a smooth-skinned freshwater fish with an almost entirely cartilaginous skeleton and a paddle-shaped rostrum (snout), which extends nearly one-third its body length. It has been referred to as a freshwater shark because of its heterocercal tail or caudal fin resembling that of sharks, though it is not closely related. The American paddlefish is a highly derived fish because it has evolved specialised adaptations, such as filter feeding. Its rostrum and cranium are covered with tens of thousands of sensory receptors for locating swarms of zooplankton, its primary food source. The only other species of paddlefish that survived to modern times was the Chinese paddlefish (Psephurus gladius), last sighted in 2003 in the Yangtze River in China and considered to have gone extinct no later than 2010.

The American paddlefish is native to the Mississippi River basin and once moved freely under the relatively unaltered conditions that existed prior to the early 1900s. It commonly inhabited large, free-flowing rivers, braided channels, backwaters, and oxbow lakes throughout the Mississippi River drainage basin, and adjacent Gulf Coast drainages. Its peripheral range extended into the Great Lakes, with occurrences in Lake Huron and Lake Helen in Canada until about 1917. American paddlefish populations have declined dramatically primarily because of overfishing, habitat destruction, and pollution. Poaching has also been a contributing factor to its decline and is liable to continue to be so as long as the demand for caviar remains strong. Naturally occurring American paddlefish populations have been extirpated from most of their peripheral range, as well as from New York, Maryland, Virginia, and Pennsylvania. They have been reintroduced in the Allegheny, Monongahela and Ohio river systems in western Pennsylvania. However, their current range has been reduced to the Mississippi and Missouri River tributaries and Mobile Bay drainage basin. American paddlefish are currently found in twenty-two states in the U.S., and are protected under state, federal and international laws.

Chondrostei is a subclass of non-neopterygian ray-finned fish. While the term originally referred to the paraphyletic grouping of all non-neopterygian ray-finned fish, it was redefined by Patterson in 1982 to be a clade comprising the Acipenseriformes (which includes sturgeon and paddlefish) and their extinct relatives.

Taxa commonly suggested to represent relatives of the Acipenseriformes include the Triassic marine fish Birgeria and the Saurichthyiformes, but their relationship with the Acipenseriformes has been strongly challenged on cladistic grounds. Coccolepididae, a group of small weakly ossified Jurassic and Cretaceous fish found in both marine and freshwater environments, have also been suggested to be close relatives of the Acipenseriformes. However, this has never been subject to cladistic analysis. Near & Thacker (2024) also recovered the ptycholepiform Boreosomus as a stem-acipenseriform.