IMPACT OF CLIMATE CHANGE ON FISH BIODIVERSITY OF HAKALUKI HAOR IN BANGLADESH

Abstract

A study was conducted to investigate the impact of climatic change on fish biodiversity of Hakaluki haor for a period of one year from July 2013 to June 2014 based on direct fish catch sampling, interview including focus group discussion in three representative sites viz. Barolekha (Gollar beel), Khulaura (Nagua beel) and Fenchuganj (Gilachaki beel). It was observed a total of 82 fish species belonging to 9 orders under 22 families of 54 genera; Among the order Cypriniformes covered 35.37%, Beloniformes 2.44%, Osteoglossiformes 2.44%, Perciformes 28.05%, Siluriformes 25.61%, Clupeiformes 2.44% and the rest were 3.66% from other fish species. Among the families, Belonidae covered 1.22%, Hemirhamphidae 1.22%, Aplocheilidae 1.22%, Cyprinidae 31.71%, Cobitidae 3.66%, Schilbeidae 6.10%, Notopteridae 2.44%, Ambassidae 4.88%, Anabantidae 7.32%, Channidae 6.10%, Cichlidae 2.44%, Gobidae 1.22%, Mastacembelidae 3.66%, Nandidae 2.44%, Synbranchidae 1.22%, Bagridae 10.98%, Clariidae 2.44%, Heteropneustidae 1.22%, Schilbeidae 6.10%, Siluridae 3.66%, Tetraodontidae 1.22% and Sisoridae 1.22% of total fish species. The present condition of families compared with twenty five years back is very much alarming where Belonidae, Hemirhamphidae, Aplocheilidae, Cyprinidae, Cobitidae, Clupeidae, Engraulidae, Notopteridae, Ambassidae, Anabantidae, Channidae, Gobidae, Mastacembelidae, Nandidae, Synbranchidae, Bagridae, Clariidae, Heteropneustidae, Schilbeidae, Sisoridae, Siluridae and Tetraodontidae families were existed in 100%, 50%, 100%, 54.17%, 20%, 50%, 0%, 100%, 100%, 120%, 100%, 50%, 100%, 100%, 100%, 47.37%, 200%, 100%, 62,50%, 11.11%, 100%, 100%, respectively and Syngnathidae, Dasyatidae, Amblycipitidae, Sciaenidae, Mugilidae, Chacidae, Olyridae, Psilorhynchidae and Anguillidae are reduced to zero percent (0%) in the last two decades and newly introduced genus is Cichlidae. However, Cichlidae has reinstated in the haor which might be due to stocking and beel nurseries programme in this area including escaping species from aquaculture due to flood. About 76.67%, 70%, 60% and 56.67% of the respondents mentioned that flood, drought, rainfall, and temperature is responsible for decreasing fish biodiversity in the haor. Moreover, 6.67% respondents mentioned cyclonic effect is also responsible for diminishing fish biodiversity. Besides, seasonal changes, pollution, lack of water, habitat destruction, fishing by completely drying and siltation are also important causes of fish biodiversity degradation of the haor area. The temperature was recorded 29±0.5 C during observation and it was also observed the average temperature 29.50 o 0 C in the year of 2009 to 2013, respectively. The average rainfall was 300mm which is higher than optimum range in the haor and 219.544mm, 325.906mm, 285.063mm, 288.937mm and 318.472mm rainfall were recorded in 2009, 2010, 2011, 2012 and 2013, respectively. The variable climatic factors, breeding and spawning of fish species are being changed so that the every year number of species is decreasing every year; and already 33 species have been lost within 25 years. Therefore, it is the proper time to take necessary steps by the stakeholders and the competent authority for saving this natural waterbody and resources for our own interest and future generation. 0 0 C, 29.00 0 C, 29.08 0 C, 28.92 C and 29