The Aral Barbel remains extant throughout most of its former range, but declines are estimated in its global population (minimum of 50% over the last three generations), area of occupancy (AOO), extent of occurrence (EOO), extent and quality of suitable habitat, and number of mature individuals. In addition, over-exploitation through above-quota or illegal fishing is regarded as a major ongoing threat. It is therefore assessed as Endangered under Criterion A (A2cd).

This species is endemic to the Caspian and Aral Sea basins including their tributary river systems, the larger channels of which it enters to spawn (see 'Habitats and Ecology').

In the Caspian region it has been extirpated from the lower Volga and Ural rivers, and now occurs only in the western and southern portions of the sea basin. In southwestern Russia it remains extant in the lower Terek River, but appears to have been extirpated from the lower Samur River at the border with Azerbaijan. It has also disappeared from most of the lower Kura River in Azerbaijan, although an isolated and landlocked subpopulation survives in the Mingachevir reservoir and affluent Alazani River. Elsewhere in Azerbaijan it continues to enter the lower reaches of several smaller river systems, including the Lankaran, Dyzdaru, Tanqərü (Tangaru) and Astara.

It is unlikely that reproductive subpopulations remain in Iran. There are sporadic recent records from the Sefīd-Rūd and Gorganrūd rivers, but these are likely to comprise vagrant foraging individuals. In general, it is now considered extremely rare in the southern Caspian basin.

In the Aral basin, it remains present in the Amu Darya, Syr Darya and Chu river systems, plus the remnant Small (northern) Aral Sea. It mostly inhabits the lower reaches of the Amu Darya, with very few records further upstream since the turn of the century. In the Syr Darya it is still present between the Small Aral Sea and Chardara Dam in southern Kazakhstan. Its status in the Chu system is unclear, but it has not been collected during field studies since at least the mid-2000s.

During the 1930s it was introduced to the Ili River, the principal affluent of Lake Balkhash in southeastern Kazakhstan, but does not appear to have become established.

Although this species' global population status has not been explicitly quantified, significant recent declines have been reported throughout its range. In the Caspian Sea it declined sharply during the mid-20^th century and has suffered an additional estimated decline of 50-80% over the last 30 years (c. three generations), while in the Aral basin it may have declined by as much as 90% since the 1970s, including an estimated minimum of 50% within the last 30 years. These declines are predicted to continue based on the ongoing nature of the threats facing the species (see 'Threats').

The Aral Barbel is semi-anadromous, with adults naturally inhabiting the brackish and endorheic Caspian and Aral seas, and migrating considerable distances up affluent rivers to spawn on an annual basis. At sea it mostly forages in littoral zones to depths of around 25 metres, while in rivers it migrates up larger, deeper channels to reach its traditional spawning grounds, which comprise fast-flowing, shallow stretches with substrates of gravel and stones.

While it still undertakes spawning migrations into the lower reaches of rivers in the western Caspian Sea and Syr Darya River, it is now fully land-locked in the Amu Darya River (see 'Threats') and adult individuals are thought to survive in the main river channel and major artificial canal systems outside of the reproductive period. Similarly, an isolated subpopulation in the Kura River (Azerbaijan) inhabits the Mingachevir reservoir, and adults migrate between this artificial lake and the inflowing Alazani River.

Sexual maturity is attained at 5-7 years of age and 500-700 mm standard length, with females maturing later than males. Generation length is estimated at 10-12 years. Reproduction occurs during two annual periods, the first of which takes place from late spring to summer, peaking when water temperatures reach 23-27°C. In addition, some individuals migrate to rivers during late summer and autumn and overwinter there before spawning the following spring. It is a highly fecund, fractional (i.e., females release batches of eggs at intervals during the reproductive period) spawner, and fully-mature females can release as many as 1,250,000 eggs per year. These hatch (c. 2 days at 25°C) while drifting in the water column, and the fry spend up to 12 months developing in reaches with slow flow before actively making their way further downstream.

This species feeds mostly on benthic crustaceans and other zoobenthos. Migrating individuals do not feed, but resume foraging behaviour following arrival at spawning sites, during which periods the eggs and fry of other fish species may be consumed in addition to aquatic invertebrates. Algae and other plant material is rarely consumed.

This species' decline has primarily been driven by anthropogenic modification of the rivers to which it migrates for breeding. In particular, the construction of dams for water retention and hydroelectricity generation has blocked access to many of its traditional spawning grounds and disrupted downstream flow regimes. Many natural river channels have also been canalised for flood prevention which has further reduced the extent of suitable spawning habitat.

In the Caspian region, the most extreme example is the cascade of large dams constructed on the Volga River and its tributaries between the 1930s and 1970s, which has largely eradicated anadromous fish species from the northern part of the Caspian basin. Smaller dams have been built on the majority of inflowing rivers throughout the western and southern Caspian basins, and the Aral Barbel is now only able to spawn where suitable habitat exists below these. In most cases it is thus restricted to reaches of only a few kilometres in length.

In 1960 the Aral Sea was the world's fourth largest inland water body and supported an important commercial fishery. However, construction of dams and vast, inefficient irrigation systems such as the Karakum Canal between the early 1960s and late 1980s led to increasing and unsustainable water abstraction from the inflowing Amu Darya and Syr Darya river systems. The loss of discharge from these rivers, coupled with a series of droughts which further reduced surface flow, drove rapid desiccation and salinisation of the sea. By 1981 most native fish species, including the Aral Barbel, had been lost (but see 'Conservation'). The Aral Barbel was also extirpated from the trans-boundary Lake Sarygamysh (shared between Kazakhstan and Uzbekistan), to which it was passively introduced via irrigation canals, plus the man-made Aydar-Arnasay lake system in Uzbekistan, due to overfishing and increasing salinity of the lakes' water.

The main current threat is above-quota or illegal fishing, which is ubiquitous throughout the Caspian and Small Aral seas despite the introduction of licenses and other regulations in some countries (e.g., Azerbaijan, Kazakhstan). Potential but less well-documented threats include extraction of gravel and sand, pollution due to discharge of untreated domestic sewage and runoff from agriculture, and unchecked introduction of non-native fish species.

This species was formerly an important component of commercial fisheries in the Caspian and Aral basins, but both stocks have more-or-less collapsed (see 'Population' and 'Threats'). In the Caspian it is still taken if caught, but is mostly regarded as bycatch. In the Aral it is still harvested on a commercial basis in the Amu Darya River system, and on an illegal basis in the Small Aral Sea following its partial restoration (see 'Conservation'). The current value of the fishery in either sea basin is unclear, but unlikely to be significant.

Commercial fishing of the Aral Barbel has been banned in Azerbaijan since 2013 and Kazakhstan since 1991. In the latter country it is listed as Endangered in the national Red Book of threatened species.

Work to partially restore the Aral Sea appears to have benefitted the Syr Darya River subpopulation. Drying of the sea had by 1978-1989 resulted in its separation into two separate waterbodies, referred to as the Small (northern) and Large (southern) seas. The Syr Darya River flows into the Small Sea, and the Amu Darya River into the Large Sea. A channel connecting these two remnant lakes across a portion of dried-up bed formed, permitting some water to enter the Large Sea from the Small Sea during periods of high discharge from the Syr Darya. In 1992 an earthen dam was constructed to prevent outflow from this channel in an attempt to improve conditions in the Small Sea. Although this dam was partially successful in raising the water level, it was repeatedly breached during spring flood events and had to be rebuilt on an annual basis, before eventually being destroyed in a storm during 1999. In 2004 and 2005, a more secure dam was built and a series of additional projects were undertaken to improve flow in the lower Syr Darya. The Small Sea water level has since stabilised, leading to reduced salinity, the reestablishment of native fishes, and resumption of small-scale commercial fishing.

The Aral Barbel is among the species to have returned, albeit to date it is present only in small numbers. The Kazakhstan government has revealed plans for a second phase of the Small Aral restoration project, which will involve further increasing its surface area. Meanwhile, the Large Aral has continued to receive very little water from the Amu Darya and by 2011 it had split into three hypersaline parts. Efforts to restore the Amu Darya delta are ongoing since the late 1980s, but have been complicated by the river's regular low-flow cycles, and work to improve the ecological status of the Syr Darya delta is also underway.

The combined effect of these projects on the respective Aral Barbel subpopulations is currently unclear.