This species does not approach the range thresholds for Vulnerable under Criterion B (extent of occurrence (EOO) < 20,000 km², area of occupancy (AOO) < 2,000 km²) or D2. There is no evidence that any population size reduction approaches the threshold for Vulnerable under Criterion A (≥ 30% over the past ten years or three generations). The population size does not approach the thresholds for Vulnerable under Criterion C (< 10,000 mature individuals) or D1, and there exists no quantitative analysis of extinction probability which would permit application of Criterion E.

Therefore, the Common Bream does not currently meet the thresholds for any Red List criteria, and it is assessed as Least Concern.

This species is native to the majority of Europe in addition to parts of Western and Central Asia.

In the European Atlantic basin it is present from southern Norway to the Adour River system in southwestern France, and throughout central and southern Great Britain.

Across the remainder of Europe and Western Asia it inhabits most rivers draining to the Baltic, White, Barents and Black sea basins, including the Sea of Marmara.

In the Mediterranean Sea basin its range is limited to southern France plus a handful of lake and river systems draining to the northern Aegean Sea.

In Central Asia it occurs in the Caspian and Aral sea basins.

It has been widely introduced outside of its native range, and is established in Ireland, central Scotland, the Muga River system in northeastern Spain, several major rivers in northern and central Italy, the Neretva River system in Croatia/Bosnia and Herzegovina, the Vardar River system (Tikveš Reservoir) in the Republic of North Macedonia, the Yeşilırmak River system in northern Republic of Türkiye, the Lake Urmia basin in the Islamic Republic of Iran, the upper Ob River system in the Russian Federation and northwestern China, the Lake Balkhash basin in Kazakhstan and northwestern China, and the Lake Baikal/upper Yenisei River system in the Russian Federation and Mongolia. It may have recently been introduced to North Africa.

This species' population size is unknown, but significantly exceeds the minimum threshold for Red List criteria (< 10,000 mature individuals). The current population trend has not been quantified, and the number of subpopulations is unclear.

It is estimated to be declining in some parts of the Black and Caspian sea basins, but reportedly remains common and abundant throughout the majority of its native range.

Localised declines in other areas, e.g., metropolitan France between 1990 and 2009, have largely been linked to improving water quality after earlier increases in abundance due to eutrophication (see 'Habitats and Ecology').

This gregarious, comparatively large-bodied species typically inhabits lentic and sluggish lotic habitats with dense patches of aquatic and/or riparian vegetation, such as lowland river channels, floodplains and natural lakes.

It is eurytopic and thus able to breed prolifically in artificial lakes, ponds, canals and irrigation ditches, while tolerating a wide range of temperatures and oxygen concentrations. It also demonstrates nomadic migratory behaviour in response to changes in food availability. For example, individuals of subpopulations inhabiting the lower reaches of rivers forage in low-salinity brackish environments on a regular basis, while lacustrine subpopulations often undertake diel foraging movements between littoral and pelagic zones. In some larger rivers, downstream wintering migrations in response to seasonally higher flow rates have been observed, while in other cases the fish move into backwaters during winter. Conversely, some subpopulations move upstream from brackish foraging areas into deep, slow-moving river stretches or fluvial lakes during winter where they sometimes form large aggregations alongside other fish species.

It is primarily an omnivorous benthivore, feeding on aquatic invertebrates and other zoobenthos, plus some organic detritus. Mouthfuls of sediment are ingested and food items are selectively retained, with inedible particles ejected through the gills into the water column. This foraging activity typically drives nutrient release and resuspension of sediment particles from the substrate, which in a well-functioning ecosystem can enhance phytoplankton productivity, accelerate nutrient fluxes and benefit organisms occupying higher trophic levels, including other fish species.

However, if Common Bream biomass reaches a critical threshold for a given aquatic system, turbidity can increase to the extent that macropyhte growth is inhibited with additional impacts on the population size and structure of both planktivorous and piscivorous fishes. Such consequences are typically evident in the conversion of shallow, clear-water, macrophyte-dominated lakes and ponds to turbid, unvegetated habitats with increased eutrophication rates.

Moreover, in highly-eutrophic systems this species is able to successfully switch its feeding mode and specialise on suspended zooplankton by filtering mouthfuls of water through the gills. Older Common Bream individuals tend not to be targeted by piscivores due to their large size, and hypertrophic lake systems thus often contain high densities of adults which dominate the fish community. In some cases, particularly in the west of its range, this has prompted lake restoration efforts which aim to reduce or remove resident subpopulations.

This species is relatively long-lived and can exceed 20 years of age. Adults typically measure 35-55 cm in length and 1.5-3.0 kg in weight, although older specimens exceptionally surpass 70 cm and 5.0 kg.

Individuals usually become sexually mature at age 3-4+, sometimes later, and the annual reproductive period extends from April to June when water temperatures exceed 12°C. In closed systems such as lakes, some individuals may mature at a smaller size than in fluvial subpopulations, particularly when overall abundance is high.

Reproductive individuals form aggregations when spawning. Lacustrine subpopulations tend to spawn in shallow littoral zones but may also enter tributaries, whereas fluvial subpopulations most often utilise backwaters or floodplains. Alternatively, subpopulations inhabiting larger river systems such as those flowing to the Black and Caspian seas may migrate several hundred kilometres upstream from their brackish feeding grounds in order to spawn. In some cases individuals exhibit a high degree of fidelity to both foraging and spawning sites.

These diverse spawning strategies appear to be dependant on specific environmental conditions and also extend to egg-deposition, with females in some subpopulations annually releasing several batches of eggs at intervals of 7-14 days and others spawning on only a single occasion which may comprise several consecutive days. Some female individuals do not spawn every year.

Fully-mature nuptial male individuals develop characteristic epidermal tubercles on the head and body, and field observations suggest that they are territorial during the reproductive period, displaying aggression towards other males as they attempt to defend prime spawning locations. Younger, non-territorial males may attempt to spawn with females entering these areas through "sneaking" behaviour. This species is polygamous, meaning males may spawn successively with multiple females, and vice versa.

The adhesive eggs are attached to submerged vegetation and other surfaces. Incubation is reported to last for 7-10 days, and hatched larvae feed on their yolk sacs for a further 7-8 days at which point they become free-swimming. Juveniles feed mostly on plankton but become increasingly benthivorous as they grow. Survival rates are greater in backwaters, but growth is more rapid in larger river channels. Young individuals often form large aggregations and perform diel foraging movements from backwaters to larger river channels.

The Common Bream naturally hybridises with sympatric members of the family Leuciscidae, particularly White Bream (Blicca bjoerkna), Common Roach (Rutilus rutilus) and Eurasian Rudd (Scardinius erythrophthalmus).

This species is not generally considered to be threatened throughout the majority of its range.

Nevertheless, some subpopulations are reportedly at risk of overharvesting, e.g., those inhabiting the lower Dnieper and Southern Bug rivers in Ukraine, Ural River system in Kazakhstan and Russia, Rybinsk Reservoir (Volga River system) in Russia and the Southern Caspian Sea basin in Iran.

In addition, extensive habitat modification has occurred throughout the Common Bream's range since the 19^th century. In particular, damming of lowland river channels has blocked annual migration routes, while canalisation and floodplain drainage has reduced the extent of available spawning grounds (see 'Habitats and Ecology').

The Common Bream is among the most important freshwater species exploited by commercial fisheries throughout much of its range. For example, in the Romanian section of the Danube River main stem it was the second-most abundant species, comprising 11.66% of commercial fish landings between 2008-2018.

According to FAO figures, global capture production since 2010 has fluctuated between c. 41,800 and c. 63,000 tonnes.

Minimum landing size requirements are in place in several countries in order to manage commercial harvesting, e.g., Estonia, Serbia, Ukraine, Islamic Republic of Iran.

Its introduction to areas outside of its natural range has also been largely driven by commercial interests, e.g., the Irtysh River in the upper Ob River system (Russian Federation and China).

This species has not traditionally been utilised in aquaculture projects, but production has increased in recent years. According to the FAO, global aquaculture production increased from c. 184 tonnes in 2010 to c. 1,300 tonnes in 2021.

This species is also popular in recreational fisheries, and is often stocked into lakes and ponds for this purpose.

This species is not protected at the international scale. No coordinated conservation management plan exists, but numerous subpopulations occur within the boundaries of protected areas.

Translocation efforts aiming to reinforce abundance at the site scale have taken place in the Islamic Republic of Iran, using individuals sourced from Azerbaijan.

It is recommended that future research should investigate reported declines in the Black and Caspian sea basins.