Global and European regional assessment: Near Threatened (NT)
EU 27 regional assessment: Near Threatened (NT)

The Pamvotida Chub is endemic to southern Albania and western Greece where it occurs in a range of habitats, from small lowland rivers and spring-fed deltaic wetlands to higher-altitude reaches descending through steep-sided valleys. It has a restricted range (extent of occurrence (EOO) c. 12,121 km², EU 27 member states 10,245 km²), which meets the threshold for the Vulnerable category under Criterion B1 (EOO < 20,000 km²). The extent and quality of habitat are estimated to be declining due to a range of threats which include pollution, channelisation and the construction of dams, but it is not understood to be severely fragmented, the number of locations is unknown, and there is no evidence that it demonstrates extreme fluctuations. Therefore, this species is assessed as Near Threatened, because it is close to qualifying for Vulnerable under Criterion B, both globally and in the EU 27 member states.

This species is endemic to southern Albania and western Greece, where its range extends southward from the Lake Butrint basin to the Ambracian Gulf. It is present in the Bistricë, Pavllë (el. Παύλα), Thyamis (el. Θύαμις), Acheron (el. Ἀχέρων), Louros (el. Λούρος) and Arachthos (el. Άραχθος) river catchments, plus Lake Pamvotida (el. Παμβώτιδα) and some coastal wetland systems.

This species' current population size and trend have not been quantified, and the number of subpopulations is unclear.

Overall abundance is understood to have decreased significantly since the mid-20^th century. In particular, there are no recent reports from Lake Pamvotida, while a marked reduction of native fishes has been observed in some parts of the Arachthos, Louros and Thyamis rivers (see 'Threats').

The Pamvotida Chub inhabits a rugged mountainous area with a mostly karstic geology. It occurs in a range of habitats, from small lowland rivers and spring-fed deltaic wetlands to higher-altitude reaches descending through steep-sided valleys. With the exception of Lake Pamvotida, it exhibits a preference for clear, flowing water, but might also enter artificial accumulation lakes resulting from dam construction (see 'Threats').

Lake Pamvotida lies within the southern portion of the Ioannina basin, which comprises an isolated depression located at 470 metres AMSL. It has an average depth of four metres, with drainage occurring via a series of ponors that transport water to the adjacent Arachthos, Louros and Thyamis river systems through subsurface karstic conduits. The northern part of the basin was formerly occupied by Lake Lapsista (el. Λαψίστα), which was drained during the late 1950s (see 'Threats').

This species is likely to feed on invertebrates alongside smaller amounts of organic detritus, plant material and perhaps smaller fishes.

Its life history has not been well-studied, but the annual reproductive period is understood to take place in spring and early summer. Anecdotal evidence suggests that some fluvial subpopulations may migrate to particular upstream spawning sites.

The construction of dams, sills, weirs and other barriers throughout this species' range has altered natural flow and sedimentation regimes, fragmented subpopulations and plausibly reduced the extent of suitable habitat for all life stages. Hydroelectric schemes associated with some dams have created unnatural flow and water temperature (hydropeaking and thermopeaking) regimes which bring about artificial dewatering of downstream river stretches and the loss of stable nursery habitat for juveniles. Furthermore, the combined effect of hydropeaking, dam flushing operations, changes in land use, and the removal of riparian vegetation may have increased the accumulation of fine sediments at some spawning sites, which could impair the hatching and survival rates of eggs and larvae.

Habitat quality has been further diminished by bank stabilisation, channelisation, drainage of wetlands and other efforts to enhance flood protection or exploit water resources. For example, the lower Arachthos River flows through the fertile Plain of Arta, which is heavily-exploited for livestock production, irrigated agriculture and food processing. An open canal irrigation system extends over much of the river's delta, and largely unregulated water abstraction is leading to the salinisation of groundwater and a reduction in the extent of suitable habitat for freshwater taxa. Extensive modification of the upper Louros river channel took place during November 2022, when a series of embankments were created by depositing boulders and material excavated from the riverbed and banks along its margins. Riparian and aquatic vegetation were removed, and a 10-kilometre stretch of the river was temporarily dewatered.

Diffuse and point source agricultural, domestic and industrial pollution has reduced the extent and quality of habitat at some locations due to eutrophication or discharge of toxic substances. Point source outputs are scattered along the main stems of most rivers and their tributaries, while intensive agriculture dominates lowland floodplains. The upper Thyamis River periodically receives polluted water from the Ioannina basin (see below).

Some upstream habitats may also have been damaged by the extraction of riverine gravel or or other sediments for urban development.

This species' decline in Lake Pamvotida is understood to have been driven by deteriorating water quality attributed to a series of events triggered by the draining of Lake Lapsista in 1959. This was followed by the rapid development of irrigated agriculture and urbanisation in the Ioannina basin, including the construction of dykes which altered the hydraulic connection between the lake and its karstic aquifer, and increased discharge of untreated agricultural, domestic and industrial waste. The lake has been severely eutrophic since the mid-1980s and is currently hypertrophic throughout the dry summer months, when its surface area is reduced due to intensive water abstraction and blooms of potentially toxic blue-green algae (Cyanobacteria) occur. During wetter parts of the year, nutrient-enriched water drains directly from the lake to the Thyamis River via an artificial ditch and tunnel system constructed during the early 1960s. Non-native fish species established in Lake Pamvotida include the Eastern Mosquitofish (Gambusia holbrooki), Common Carp (Cyprinus domestic strain), Prussian Carp (Carassius gibelio) and Achelous Roach (Rutilus panosi), all of which may negatively impact native taxa through resource competition, predation of early life stages, habitat degradation or transmission of pathogens.

The negative impact of some threats could plausibly be exacerbated by increasingly rapid climate change in the Mediterranean region, which is already driving extended periods of drought.

This species is not used or traded.

This species is present within the boundaries of numerous protected areas, including Butrint (Albania) and Amvrakikos Wetlands (Greece) national parks, both of which are also listed as Ramsar Wetlands of International Importance (sites 1290 and 61, respectively). In Greece, a number of these are included in the European Union's Natura 2000 network, e.g., sites GR2110002, GR2130004, GR2130005 (Lake Pamvotida), GR2130008 and GR2140001.

No specific conservation measures are in place, and a deeper understanding of its demographics (population size and trend) and life history, e.g., the identification of key spawning sites, would likely prove useful in the development of future management efforts.