[6] Heavily fished for the female's valuable roe, known as beluga caviar, wild populations have been greatly reduced by overfishing and poaching, leading IUCN to classify the species as critically endangered.

The barbels are laterally compressed with foliate appendages, arranged in two pairs, originating midway or closer to the mouth than to the tip of the snout.

[10] Among sturgeons, only the closely related Kaluga (Huso dauricus) can attain similar size, with a maximum weight of 1,000 kg (2,200 lb).

Beluga of such great sizes are very old (continuing to grow throughout life) and have become increasingly rare in recent decades because of heavy fishing of the species.

[7] Due to rampant overfishing, the average lifespan of beluga sturgeon is unknown, with no specimens living past their 56th year.

[15] Like most sturgeons, the beluga is anadromous, migrating upstream in rivers to spawn on clean, hard substrate, which offers both support and cover to their sticky and adhesive eggs.

[18] The piscivorous diet of beluga sturgeon tends to change with age: in the Caspian Sea, it mainly consists of Clupeonella sp.

It has been reported that in marine and brackish environments, adult Adriatic H. huso foraged primarily on molluscs (Cephalopoda, of which common cuttlefish, Sepia officinalis, and European squid, Loligo vulgaris, are particularly common in the Adriatic Sea) and fish belonging to the families Gadidae, Pleuronectidae, Gobiidae, Clupeidae, Scombridae and Mugilidae, but also on big crustaceans; in the rivers, they fed mainly on local Cyprinidae.

[9] Beluga sturgeon are considered euryhaline, capable of moving freely between freshwater and estuaries, and thus can live in waters of varying saline content.

The Mediterranean population is strongly protected under Appendix II of the Bern Convention, prohibiting any intentional killing of these fish.

[28] Then, after the building of a fish ladder on Isola Serafini dam, on 2019 hundreds of young microchipped beluga and 60 tagged subadults were released into the Po river, following EU Projects (Life Ticino Biosurce).

[30] Management of sturgeon fisheries within the Caspian Sea began in the 1950s and while the initial regulations had honorable intentions, they achieved dwindling effects due to the ever present demand for the fish's caviar.

In 2021, two Romanian men in Grindu, Ialomita, were caught trying to smuggle a 140 kilogram, 2.5-metre beluga sturgeon in a wagon; the fish was later safely returned to the river.

The excessive harvesting and a sharp increase in poaching have removed the largest and most mature specimens from the population, almost eliminating natural reproduction.

These dams have blocked access to crucial river habitats, leading to a significant reduction in the species' ability to reproduce.

Similar habitat loss has occurred in other rivers due to dam construction, greatly impacting the species' survival.

The species' long lifespan makes it vulnerable to pesticide contamination, resulting in reduced reproductive success and other health issues.