Note on mass mortality of Bloch’s gizzard shad at Dhanushkodi lagoon, Tamil Nadu

Mass mortality of Bloch’s gizzard shad, Nematalosa nasus (Bloch, 1795) was observed around 5 km shore area of the lagoon from Ottathalai to Thavukadu near near the Kothandaramar Temple, Dhanushkodi, Ramanathapuram District, Tamil Nadu on 19th October 2019. An estimated 3 tonnes of Nematalosa nasus were washed ashore and water samples collected from the site were analysed indicated Dissolved oxygen (2.17ppm), pH (7.83ppm), salinity (40ppt), temperature (30.6oC), ammonia, nitrite and nitrate (0.1, 0.2 and 0.43 ppm respectively).