Beluga sturgeon
Fish · Last reviewed 2026-08-19
The largest fish that has ever entered European fresh water, a survivor of a lineage older than the dinosaurs, and now Critically Endangered — a fish this catalogue describes so it can be recognised and released, not caught.
Safety
Fish welfare — Can cause serious injury or death
This is a Critically Endangered species in which every mature individual represents fifteen to twenty years of growth and is one of very few remaining breeders. A fish killed, injured, or exhausted and released badly is not a fish lost from a stock — it is a measurable fraction of a population's remaining reproductive capacity. The species' late maturity means the damage is invisible for a decade and a half.
What reduces it: Keep it in the water, support it horizontally, never suspend it vertically or lift it by the tail, minimise the fight and the handling time, release immediately, and report the capture if the jurisdiction requires it. If in any doubt about what a sturgeon is, treat it as protected.
Worse when:
- Warm, low-oxygen water in the lower river and delta in summer, where a long fight is far more damaging
- Heavy tackle handling on a bank rather than in the water
- Any assumption that a sturgeon caught in one country may be treated as one caught in another
Hooks and barbs — Minor injury
The five rows of bony scutes are sharp, particularly on smaller fish where they are least worn, and a strong fish moving against a hand draws blood readily. The mouth is toothless and harmless; the body is the hazard.
What reduces it: Handle with wet hands and support from beneath rather than gripping, keep the fish in the water, and use long forceps for unhooking rather than reaching into the mouth.
THE BELUGA IS THE LARGEST FRESHWATER-ENTERING FISH EUROPE HAS EVER HAD, AND IT IS ALMOST GONE.
Historical records describe fish of several metres and over a tonne running out of the Black Sea and the Caspian and far up the Danube, the Volga and the other great rivers. Nothing else in European fresh water approaches it. It is not closely related to the fish an angler normally meets: sturgeons are an ancient lineage with a cartilaginous skeleton, a heterocercal tail like a shark's, five rows of bony plates called scutes instead of scales, and a toothless protrusible mouth slung underneath a long snout. The group predates the dinosaurs and has changed remarkably little.
IT IS ANADROMOUS AND EXTREMELY SLOW TO MATURE, WHICH IS THE WHOLE PROBLEM. Beluga live in the sea and run into rivers to spawn on gravel far upstream. They can live well over fifty years and do not mature until they are around fifteen to twenty, and females do not spawn every year. A population of a fish like that cannot absorb sustained adult mortality: by the time a shortage is visible in the catch, decades of recruitment have already been removed.
THREE THINGS DESTROYED IT AND THEY COMPOUNDED. Dams cut the migration — the Iron Gates barrages on the Danube are the decisive example, closing off the upper river entirely. A fishery driven by the caviar trade, in which the roe of a mature female is among the most valuable animal products in the world, removed the mature fish that could still reach spawning grounds. And the eggs are laid on clean gravel in fast water, which dredging, damming and sediment change have degraded through much of the remaining accessible river.
IT IS ASSESSED AS CRITICALLY ENDANGERED and it is protected across its range, with the international trade in its products separately controlled. Restocking programmes release hatchery-reared juveniles into the Danube and elsewhere, so a small beluga in the lower river may be a released fish rather than a wild-spawned one — which matters for what the population's recovery actually means.
THIS RECORD EXISTS SO THE FISH CAN BE RECOGNISED, NOT PURSUED. FishingHQ does not treat it as quarry.
Identification
FishingHQ holds no photograph of this species whose identity and licensing it can vouch for, so it is not showing one. Misidentified fish photographs teach identification wrongly, and a picture with an unchecked caption would be worse than none. The identification points below are what to look at instead.
- Scientific name
- Huso huso
- Family
- Acipenseridae
- Water
- Moves between fresh and salt water
- Conservation status
- Critically Endangered
- Regions
- Central & Eastern Europe, Mediterranean
- Five rows of bony scutes running the length of the body — one along the back, one along each flank and one along each side of the belly — instead of scales. Any fish with these is a sturgeon, and that is the first and easiest determination.
- A shark-like tail with the upper lobe distinctly longer than the lower, and a cartilaginous skeleton. Both are ancient characters and neither belongs to any ordinary European freshwater fish.
- A toothless mouth on the underside of the head that extends outwards to suck food off the bottom, with four barbels in a row in front of it.
- Beluga specifically: the mouth is very large and crescent-shaped and reaches back beyond the sides of the head, which is the character that separates it from every other sturgeon in the basin. In the others the mouth is small and transverse.
- The snout is comparatively short, soft and pointed, and the barbels are flattened and carry small leaf-like appendages.
- The gill membranes are joined together beneath the throat and are free of the isthmus, which is a technical character but a reliable one and is what a specialist checks first.
- IDENTIFICATION IS GENUINELY HARD BELOW SPECIES LEVEL AND HYBRIDS EXIST. Sturgeons hybridise readily, farmed sturgeons of several species including non-native ones escape, and a hybrid can carry an intermediate mouth and an intermediate scute count. A fish that is clearly a sturgeon and not clearly a species is a fish to photograph and release rather than to identify confidently.
Size
- Typical
- Very few large fish now remain; most encountered are hatchery-origin juveniles well under a metre
- Large
- Historically 2–3 m
Exceptional: Historical records describe fish over 5 m and in excess of one tonne, and FishBase records a maximum around 800 cm. These are historical figures rather than a description of the present population.
Lifecycle and reproduction
Extremely long-lived — well beyond fifty years — and extremely late to mature, at roughly fifteen to twenty years, with females not spawning every year thereafter. Juveniles drop down to the sea and spend years growing there before their first spawning run. That combination is what makes the species incapable of absorbing adult mortality: a fish removed before it has spawned has contributed nothing, and the interval between generations is comparable to a human one.
Spawns in fast water over clean gravel far up large rivers, historically hundreds and in some rivers well over a thousand kilometres from the sea. The eggs are adhesive and need clean, well-oxygenated interstitial gravel to survive, so both access to the spawning reaches and the condition of the gravel when a fish gets there are required, and river regulation has degraded both.
Feeding and senses
Unlike the other sturgeons of the basin, which are mainly bottom feeders on invertebrates, adult beluga are predominantly piscivorous and take fish — a consequence of the very large mouth. Juveniles feed on invertebrates and small fish. Feeding is bottom-oriented and the barbels are sensory, sweeping the bed ahead of the protrusible mouth.
Heavily dependent on non-visual senses. The barbels carry taste and touch receptors and are drawn over the bottom ahead of the mouth, and the snout carries electroreceptive organs — ampullae — that detect the weak electric fields of buried prey. This is a fish built to find food in turbid water and darkness, which is exactly the water the lower Danube and the north-western Black Sea shelf provide.
Through the year
Historically ran into the rivers in more than one seasonal wave, with fish entering in spring to spawn in the same year and others entering in autumn to overwinter in the river and spawn the following spring. The autumn-running form depended on long undisturbed river reaches to hold in, and dams removed that possibility before they removed anything else.
Distribution
The Black Sea, the Caspian Sea and the Sea of Azov, with spawning migrations into the Danube, the Volga, the Ural, the Dnieper and other large rivers. The range is now a fraction of its historical extent: the Danube population is confined to the reaches below the Iron Gates, and several river populations are gone entirely.
This is a biological range — where the species occurs, not a prediction that you will catch one. To browse the fishing geography FishingHQ holds, start at fishing places.
Why anglers care
NOT A QUARRY, AND THIS RECORD IS DELIBERATELY NOT WRITTEN AS THOUGH IT WERE. The beluga is Critically Endangered, protected across its range, and the subject of international trade controls and of continuing illegal exploitation that is the principal ongoing threat to it. Its relevance to an angler is that it can be encountered incidentally in the lower Danube, the delta and the adjacent coast, and that recognising one and dealing with it correctly matters. Several jurisdictions in the basin have specific mandatory procedures for an incidentally captured sturgeon, which may include immediate release, a prohibition on removing it from the water, and reporting the capture. FishingHQ states none of them and does not know which apply where; the national fisheries authority for the water being fished is the only source. Where sturgeon fishing is legitimately offered in Europe it is almost always for stocked, farmed or non-native species in enclosed commercial waters, and that is a different activity from encountering a wild beluga.
Handling and returning
If a sturgeon is caught anywhere in the Black Sea or Danube basin, assume it is a protected species until an authority tells you otherwise. Keep it in the water. Do not lift it by the tail or by the gill covers — a large sturgeon is heavy, its body is supported by cartilage rather than bone, and vertical suspension damages it. Support the body horizontally with wet hands if it must be handled at all. The scutes are sharp enough to cut a hand and the fish is strong. Photograph it in the water for identification, unhook it if that can be done without further handling and cut the line close if it cannot, and release it immediately. Then establish the reporting position with the responsible authority — several jurisdictions require a capture to be reported and that requirement exists precisely because incidental captures are one of the few sources of population data.
Where to go next
Where you will find it
- The Black SeaThe sea half of an anadromous life history that no longer completes. Beluga live here and ran into the Danube, the Dnieper and the other great rivers to spawn; the dams cut the river half, and what remains is a marine population that mostly cannot reproduce where it evolved to.
- The Danube basinThe river half, now confined to the reaches below the Iron Gates. That basin record already names this fish — 'the basin's sturgeons, beluga among them, historically the largest freshwater-entering fish in Europe' — and until this sprint the name pointed at nothing.
What these connections rest on (2)
Scientific evidence — 2 connections
Supported by peer-reviewed research or fisheries science. The sources are listed and can be checked.
The Black Sea
A distribution edge resting on published identification and distribution references rather than on angling report, written where the species is genuinely characteristic of the system rather than merely recorded in it once.
- FishBase: a global information system on fishes — Froese, R. and D. Pauly, eds. — FishBase Consortium (Scientific institute)Relied on for: Recorded environment, salinity tolerance, depth range, distribution and biology of the species named.States this directlyPassage read and verified
- FAO Species Identification Guides for Fishery Purposes and the FAO Species Catalogues — Food and Agriculture Organization of the United Nations (Scientific institute)Relied on for: Distribution, habitat association and identification of the fishes of the Mediterranean and Black Sea region.States this directlyCitation checked — the work exists and is described correctly
The Danube basin
A distribution edge resting on published identification and distribution references rather than on angling report, written where the species is genuinely characteristic of the system rather than merely recorded in it once.
- FishBase: a global information system on fishes — Froese, R. and D. Pauly, eds. — FishBase Consortium (Scientific institute)Relied on for: Recorded environment, salinity tolerance, depth range, distribution and biology of the species named.States this directlyPassage read and verified
- FAO Species Identification Guides for Fishery Purposes and the FAO Species Catalogues — Food and Agriculture Organization of the United Nations (Scientific institute)Relied on for: Distribution, habitat association and identification of the fishes of the Mediterranean and Black Sea region.States this directlyCitation checked — the work exists and is described correctly
Understanding this fish
- Fish growth, age and what a big fish representsThe most extreme case of that record's subject in European fresh water, and the reason its collapse was irreversible on a human timescale. A beluga can live beyond fifty years and does not mature until fifteen to twenty, so the interval between generations is comparable to a human one — and a fish removed before it has spawned has contributed nothing at all.
- Why fish migrateA worked example of migration as an obligation rather than a preference. Beluga must reach gravel far up a large river to reproduce, and no amount of suitable marine habitat substitutes for it. When the Iron Gates closed, the population above it did not adapt; it ended.
What these connections rest on (2)
Scientific evidence — 2 connections
Supported by peer-reviewed research or fisheries science. The sources are listed and can be checked.
Fish growth, age and what a big fish represents
A place or a fish joined to the mechanism that explains it, written where the subject is a worked example of that mechanism rather than merely subject to it.
- The IUCN Red List of Threatened Species — International Union for Conservation of Nature (Conservation authority)Relied on for: Conservation assessments of the sturgeons of the Black Sea and Danube basin, the threats recorded against them, and the basis for the extinction-risk statements made.States this directlyCitation checked — the work exists and is described correctly
- The European Environment Agency's assessments of Europe's waters, seas and coasts — European Environment Agency, Copenhagen (Conservation authority)Relied on for: Assessment of river continuity, barriers to migration and hydromorphological pressure in the Danube basin.States this directlyCitation checked — the work exists and is described correctly
Why fish migrate
A place or a fish joined to the mechanism that explains it, written where the subject is a worked example of that mechanism rather than merely subject to it.
- The IUCN Red List of Threatened Species — International Union for Conservation of Nature (Conservation authority)Relied on for: Conservation assessments of the sturgeons of the Black Sea and Danube basin, the threats recorded against them, and the basis for the extinction-risk statements made.States this directlyCitation checked — the work exists and is described correctly
- The European Environment Agency's assessments of Europe's waters, seas and coasts — European Environment Agency, Copenhagen (Conservation authority)Relied on for: Assessment of river continuity, barriers to migration and hydromorphological pressure in the Danube basin.States this directlyCitation checked — the work exists and is described correctly
Told apart from
- SterletThe comparison that decides what an angler should do. Both are sturgeons and both carry the same five rows of scutes, and almost everything else differs: beluga has a very large crescent-shaped mouth reaching back past the sides of the head, sterlet a small transverse one and a long narrow upturned snout with FRINGED barbels. Size separates a mature fish of either and does not separate a juvenile beluga from an adult sterlet. Hybrids and farm escapes make the distinction genuinely hard, which is why a sturgeon that does not clearly key out is treated as a protected species and released.
- White sturgeonSet side by side because a reader searching for sturgeon fishing will find North American material first, and it describes a different situation. White sturgeon supports a large, legitimate, heavily regulated catch-and-release recreational fishery on the Pacific coast. Beluga supports none, is Critically Endangered, and is the subject of international trade controls. The same family, and opposite answers to 'may I fish for this'.
What these connections rest on (2)
Scientific evidence — 2 connections
Supported by peer-reviewed research or fisheries science. The sources are listed and can be checked.
Sterlet
A comparison written where a reader genuinely needs the two set side by side — either because they confuse them, or because the difference between them is the thing worth knowing.
- FishBase: a global information system on fishes — Froese, R. and D. Pauly, eds. — FishBase Consortium (Scientific institute)Relied on for: Recorded environment, salinity tolerance, depth range, distribution and biology of the species named.States this directlyPassage read and verified
- FAO Species Identification Guides for Fishery Purposes and the FAO Species Catalogues — Food and Agriculture Organization of the United Nations (Scientific institute)Relied on for: Distribution, habitat association and identification of the fishes of the Mediterranean and Black Sea region.States this directlyCitation checked — the work exists and is described correctly
White sturgeon
A comparison written where a reader genuinely needs the two set side by side — either because they confuse them, or because the difference between them is the thing worth knowing.
- The IUCN Red List of Threatened Species — International Union for Conservation of Nature (Conservation authority)Relied on for: Conservation assessments of the sturgeons of the Black Sea and Danube basin, the threats recorded against them, and the basis for the extinction-risk statements made.States this directlyCitation checked — the work exists and is described correctly
- The European Environment Agency's assessments of Europe's waters, seas and coasts — European Environment Agency, Copenhagen (Conservation authority)Relied on for: Assessment of river continuity, barriers to migration and hydromorphological pressure in the Danube basin.States this directlyCitation checked — the work exists and is described correctly
Safety reading
What these connections rest on (1)
Authoritative guidance — 1 connection
Stated by a fisheries authority, scientific institute or recognised angling body. Authoritative, but summarising rather than demonstrating.
Handling fish safely
A handling edge written because the correct technique is counter-intuitive to anglers used to bony fish, and because the consequence of getting it wrong is disproportionate for this species.
- The IUCN Red List of Threatened Species — International Union for Conservation of Nature (Conservation authority)Relied on for: Conservation assessments of the sturgeons of the Black Sea and Danube basin, the threats recorded against them, and the basis for the extinction-risk statements made.States this directlyCitation checked — the work exists and is described correctly
- The European Environment Agency's assessments of Europe's waters, seas and coasts — European Environment Agency, Copenhagen (Conservation authority)Relied on for: Assessment of river continuity, barriers to migration and hydromorphological pressure in the Danube basin.States this directlyCitation checked — the work exists and is described correctly
Rules and access
What these connections rest on (1)
Authoritative guidance — 1 connection
Stated by a fisheries authority, scientific institute or recognised angling body. Authoritative, but summarising rather than demonstrating.
Protected species, and why some fish may not be taken
The edge names the CLASS of rule and never its content, which is the product's standing position. It is written because a reader who encounters this fish needs to know that a rule exists and where to ask, not because the catalogue knows what the rule says.
- The IUCN Red List of Threatened Species — International Union for Conservation of Nature (Conservation authority)Relied on for: Conservation assessments of the sturgeons of the Black Sea and Danube basin, the threats recorded against them, and the basis for the extinction-risk statements made.States this directlyCitation checked — the work exists and is described correctly
- The European Environment Agency's assessments of Europe's waters, seas and coasts — European Environment Agency, Copenhagen (Conservation authority)Relied on for: Assessment of river continuity, barriers to migration and hydromorphological pressure in the Danube basin.States this directlyCitation checked — the work exists and is described correctly
Environment and conservation
What these connections rest on (1)
Scientific evidence — 1 connection
Supported by peer-reviewed research or fisheries science. The sources are listed and can be checked.
Fish stocks and sustainability
Written because this species is the worked example the environment record needs — the case where every mechanism it describes operated at once on a fish that could not absorb any of them.
- The IUCN Red List of Threatened Species — International Union for Conservation of Nature (Conservation authority)Relied on for: Conservation assessments of the sturgeons of the Black Sea and Danube basin, the threats recorded against them, and the basis for the extinction-risk statements made.States this directlyCitation checked — the work exists and is described correctly
- The European Environment Agency's assessments of Europe's waters, seas and coasts — European Environment Agency, Copenhagen (Conservation authority)Relied on for: Assessment of river continuity, barriers to migration and hydromorphological pressure in the Danube basin.States this directlyCitation checked — the work exists and is described correctly
Check the rules before you fish
Fishing laws, bylaws, access rules, seasons, bait restrictions and permitted methods vary by location and can change. Check the current rules from the relevant authority and the water you intend to fish before fishing.
Check with:
- Current national or regional law for where you are fishing
- Current local bylaws
- The relevant fisheries authority
- The landowner, club or fishery whose water it is
- Any restrictions specific to the species or the method you intend to use
Sources for this page
- FishBase: a global information system on fishes — Froese, R. and D. Pauly, eds. — FishBase Consortium (Scientific institute)Relied on for: Family placement, maximum recorded size, environment, salinity tolerance, depth range, distribution and life history of the species named.States this directlyPassage read and verified
- The IUCN Red List of Threatened Species — International Union for Conservation of Nature (Conservation authority)Relied on for: The conservation assessment of the species named, the threats recorded against it, and the basis for the extinction-risk statements made here.States this directlyCitation checked — the work exists and is described correctly
- FAO Species Identification Guides for Fishery Purposes and the FAO Species Catalogues — Food and Agriculture Organization of the United Nations (Scientific institute)Relied on for: Morphological identification characters for the sturgeons of the Mediterranean and Black Sea region, including the characters separating confusable species.States this directlyCitation checked — the work exists and is described correctly
- The European Environment Agency's assessments of Europe's waters, seas and coasts — European Environment Agency, Copenhagen (Conservation authority)Relied on for: Assessment of Europe's surface waters including hydromorphological pressure, river continuity and barriers to migration, and the condition of the Danube basin.States this directlyCitation checked — the work exists and is described correctly
- Freshwater Fishes of the British Isles — HarperCollins (New Naturalist 75), 1992 (Reference work)Relied on for: European freshwater fish biology, life history and the characteristics of large long-lived late-maturing species.Background and mechanism onlyCitation checked — the work exists and is described correctly
How FishingHQ labels evidence is explained in the evidence policy.