Turkey: Leopard barbel thought lost rediscovered

According to a report by the non-profit conservation organization Re:wild, a team of ichthyologists recently rediscovered the leopard barbel or Mesopotamian barbel (Luciobarbus subquincunciatus) in the Turkish section of the Tigris River, after it was last documented in 2011. The rediscovery of this cyprinid marks the team’s second success, after it had already tracked down the Batman River loach (Paraschistura chrysicristinae), a species only three centimeters long that had not been seen since the 1970s, in southeastern Turkey in 2021. Both species were on the list of Re:wild and SHOAL’s most wanted lost fish species and have now been rediscovered.

Successful search for a lost fish species

The leopard barbel, once widespread over a large area from eastern Anatolia to Iraq in the Tigris-Euphrates river system, has been severely threatened over the past three decades by fishing, pollution, habitat destruction, and dam construction. Reports from local fishers suggested that the species might still exist, prompting an expert team led by Cüneyt Kaya and Münevver Oral of Recep Tayyip Erdogan University to begin searching for the missing leopard barbel in cooperation with the local fisheries and aquaculture department.

The team first analyzed the scientific literature to determine where the species had occurred in the past. However, because these data dated from before the construction of nine dams in the Turkish section of the Tigris and dams usually release cold water from reservoirs, many freshwater fish had been displaced into warmer waters. The team therefore adjusted its strategy and searched further downstream from the dams, away from the leopard barbel’s original range.

Just a few days later, Kaya and Oral received a video call from a fisher who had caught a fish 50 centimeters long and weighing two kilograms, with conspicuous black spots and the characteristic barbels around its mouth. The same fisher even caught a second specimen of the leopard barbel.

Rediscovery of the leopard barbel offers hope

The rediscovery of the leopard barbel sends a positive signal, especially against the backdrop of alarming IUCN reports at the end of 2023 indicating that 25% of all freshwater fishes are threatened with extinction. The conservation union emphasizes that dams and water extraction threaten 45% of endangered freshwater fish species. This is also evident in the case of the leopard barbel, whose population has declined drastically because of existing dams in the Turkish section of the Tigris River. In addition, the current construction of another dam in Cizre, near the site where the two rediscovered leopard barbels were found, is regarded as an additional threat to the species.

Cüneyt Kaya and Münevver Oral have ambitious plans to strengthen awareness of river systems and wildlife. To this end, the scientists want to use the rediscovery of the leopard barbel as a vivid example in seminars for fishers and teachers. It is to serve as a case study for protecting the Tigris and its unique biodiversity. In addition, the researchers hope that further studies will provide a more detailed understanding of the current population numbers of the leopard barbel and its distribution within its historical range.

The IUCN has classified the leopard or Mesopotamian barbel as “critically endangered” based on an assumed decline of more than 80% over the past 30 years.

Summary The leopard barbel (Luciobarbus subquincunciatus) was rediscovered in the Turkish section of the Tigris after this cyprinid fish species had been considered lost since 2011.Fishing, pollution, and dam construction caused a sharp population decline over the past 30 years.The rediscovery of the leopard barbel gives reason for hope, especially in light of the fact that the IUCN announced at the end of 2023 that 25% of all freshwater fishes are threatened with extinction.