Six new species of fish have been documented at the Sukhna by the department of zoology, Panjab University, which were not found in the fish biodiversity project of 2005-2006 and carp morphometric survey of 2012-2014. Under the opaque, gently-rippled waters of the Sukhna lake, lurk treasures of biodiversity.
The addition was revealed by a report — Evaluation of Fish Biodiversity in Sukhna lake for Sustainable Aquaculture Practices — prepared by the department and submitted to the chief conservator of forests and wildlife, Chandigarh. The nets were cast into the water for one hour, the catch was recovered after that, and the fish were photographed, documented and then released back into the water to avoid mortality during sampling. Of these, two species (lanchi and mirror carp) are listed as ‘vulnerable’ and one (silver carp) as ‘near threatened’ by the International Union for Conservation of Nature (IUCN). The fish samples were dominated numerically by five species, including the kalbasu, from the Cyprinidae family. “We employed three methods to sample fish. At four points on the northern shores, gillnets were cast to trap fish. On the southern bank, we sampled fish from seven points used by recreational anglers, and these yielded the maximum diversity of fish species and the best growth parameters. The project co-investigator is Dr Ashwani Kumar, joint director, animal husbandry and fisheries, Chandigarh. Kaur was assisted by research scholars Muskan Jain, Khushdeep Kaur, Chhavi Chawla, Ashita Sharma and Neha Dhiman. Of concern was the thoughtless and illegal dumping of exotic aquarium fish in the Sukhna (posing a threat to native species), as evidenced by recovered specimens of goldfish, Amazonian catfish and Nile tilapia.
The new species found during the evaluation of 2025-2026 were mola, shark catfish, Amazonian suckermouth/sailfin catfish, Nile tilapia, goldfish and barred spiny eel. In the assessments of 2005-2006 and 2012-2014, 32 and 19 fish species were recorded respectively. In the latest evaluation, 25 species of fish were detected from 289 samples. The maximum specimens, 93, were from one species, kalbasu. The fish density recorded for the catch in the gillnets was calculated at a healthy Catch Per Unit Effort (CPUE) of 9.4 and 13.4 fish/net/hour over two sampling days. Of the 25 species recorded in the evaluation, eight were exotic (common, silver, mirror, bighead and grass carps along with goldfish, Amazonian catfish and Nile tilapia).
A record of a new species (barred spiny eel) was procured from Dr Manjit Singh, who photographed an eel in the bill of a great cormorant,” associate professor Dr Ravneet Kaur, who is the principal investigator for the evaluation, told this writer. “The fish samples showed signs of good growth,” said Kaur. Ramsar criterion: The lake was recently inducted in the Ramsar List of Wetlands of International Importance under the classification of a “peri-urban reservoir”. Delving into Sukhna’s importance for fish biodiversity during adverse periods, the official Ramsar Information Sheet (RIS) published on October 15, 2026, stated that certain fish species “utilise the Sukhna wetland (Ramsar Site 2602) as a critical refuge habitat during periods of hydrological fluctuations, elevated temperatures and reduced flow conditions”.
The latest evaluation takes a step forward from the earlier fish surveys at the Sukhna by introducing baseline data for fish densities and bacterial presence in the gills and skin of fishes.
