World Journal of Zoology 7 (4): 328-337, 2012 ISSN 1817-3098 © IDOSI Publications, 2012 DOI: 10.5829/idosi.wjz.2012.7.4.6634 Biodiversity in the Padma Distributary of the Ganges River, Northwestern Bangladesh: Recommendations for Conservation 1Md. Mosaddequr Rahman, 1,2Md. Yeamin Hossain, 2Ferdous Ahamed, 34Fatematuzzhura, Bharat Raj Subba, 5Elgorban M. Abdallah and 2Jun Ohtomi 1Department of Fisheries, Faculty of Agriculture, University of Rajshahi, Rajshahi 6205, Bangladesh 2Faculty of Fisheries, Kagoshima University, 4-50-20 Shimoarata, Kagoshima 890-0056, Japan 3Department of Agroforestry, Hajee Mohammad Danesh Science and Technology University, Dinajpur 5200, Bangladesh 4Department of Zoology, Post Graduate Campus (TU), Biratnagar, Nepal 5Center of Excellence of Biotechnology Research, King Saud University, Riyadh 11451, Saudi Arabia Abstract: The Padma River is one of the longest rivers and it is believed to be an important spawning and feeding ground for riverine fish species of Bangladesh. This study analyzed the fish biodiversity and main threats to biodiversity to provide recommendations for conservation in the Padma River. Sampling was conducted fortnightly in the Padma River during March 2009 to February 2010 from fishermen catch landed at different fish landing centers between Binodpur and Godagari, Rajshahi, northwestern Bangladesh. A total of 80 species of fish under 9 orders and 24 families were recorded. Cypriniformes were most dominant order constituting 35% of the total fish population followed by Siluriformes (32.50%), Perciformes (17.50%), Clupeiformes (5.00%), Synbranchiformes (3.75%), Osteoglossiformes (2.50%), Beloniformes (1.25%), Mugiliformes (1.25%) and Tetraodontiformes (1.25%). Among the species found during the present study, 12.50% were vulnerable, 21.25% were endangered and 8.75% were critically endangered. Major threats to fish biodiversity include habitat destruction and defragmentation, water pollution, indiscriminate harvesting of fry and fingerlings, construction of barrages, construction of embankments by the Ganges-Kobadak project, sedimentation. Restocking economically important fish species, establishing and maintaining fishery sanctuaries, ordering closed seasons and combining fisheries with aquaculture, banning indiscriminate fishing and destructive fishing gears, strengthening CBOs (Community based organizations), encouraging IPM (integrated pest management), dredging, identification and protection of the breeding and nursery grounds are recommended for the conservation of fish biodiversity in the Padma River, NW Bangladesh. Key words: Cypriniformes Biodiversity Threat Conservation Padma Bangladesh INTRODUCTION their high sensitivity to the quantitative and qualitative alteration of aquatic habits [4, 5, 6]. Subsequently, Recent studies on biodiversity loss and its they are often used as bio-indicators for assessment of implications for ecosystem services have uncovered water quality, river network connectivity or flow regime unprecedented species extinctions at global and [7]. Nowadays, fish biodiversity and management of regional levels [1, 2]. Throughout the last century, associated habitats is a great challenge [8]. In addition, riverine ecosystems have suffered from intense human the conservation of aquatic biodiversity has gained great intervention resulting in habitat loss and degradation and ecological importance over recent years [9]. as a consequence, many fish species have become highly Bangladesh is exclusively endowed with extremely endangered, particularly in rivers where heavy demand is rich and extensive inland and marine water resources, placed on freshwaters. Moreover, freshwater fish are one which mainly includes floodplains, haors, baors, beels, of the most threatened taxonomic groups [3] because of rivers, estuaries, coastal belt and vast sea waters. Corresponding Author: Md. Yeamin Hossain, Faculty of Fisheries, Kagoshima University, Shimoarata 4-50-20, Kagoshima 890-0056, Japan. Tel/Fax: +81-99-286-4152. 328 World J. Zool., 7 (4): 328-337, 2012 Along with potential water resources, Bangladesh is also which in turn limits formulation of biodiversity rich in the diversity of various fish species and other conservation strategies. Additionally, in order to manage important aquatic species. Hence it is ranked third in fish fish biodiversity effectively, it is necessary to identify biodiversity in Asia behind China and India, with the reasons for decline of the species [12, 26]. Therefore, approximately 800 species of fresh, brackish and marine this study attempted to collect information on fish waters [10]. biodiversity in the Padma River, NW Bangladesh. The River Padma, second longest river of The specific objectives of this study were to (i) analyze Bangladesh, is the habitat of the richest freshwater fish the fish biodiversity, (ii) review the main threats to fish fauna of Bangladesh [11]. The Padma River is believed to biodiversity and (iii) provide recommendations for be an important spawning and feeding ground for riverine fish biodiversity conservation. fish species of northwestern Bangladesh [12]. The river conserves a rich variety of fish species which support MATERIALS AND METHODS to the commercial fisheries. A large number of fishes including some commercially important species are The current study was conducted in the Padma fished in the river by both small and large scale fishers River (lower part of the Ganges River), NW Bangladesh. throughout the year [13]. During the year 2007-2008, The River Padma is the main distributary of the Ganges a total of 9392 metric tons of fish were captured from the that originates in the Gangotri glacier of the Himalayan. River Padma which was 6.87% of the total fish captured The Ganges enters into Bangladesh from India at Shibganj from all the rivers in Bangladesh [14]. This River also Upazila of Chapai Nawabganj district (Latitude 24° 65' N; supports livelihood and nutritional security of the people Longitude 88° 06' E) where becomes known as the Padma living alongside. However, most of the wild populations River. have seriously declined in rivers and streams of Samples were collected fortnightly from commercial Bangladesh due to over exploitation augmented by catches landed at different fish landing centers from various ecological changes and degradation of the natural Binodpur to Godagari, Rajshahi (Latitude 24° 46' N; habitats [9, 15]. Longitude 88° 32' E), NW Bangladesh (Figure 1) during Several studies on the biodiversity of fish have been March 2009 to February 2010. Fish were usually caught conducted throughout the world including [16-21]. by means of the traditional fishing gears such as cast Even though a few studies have been conducted on the net (jhaki jal), square lift net (tar jal), conical trap Padma River fisheries including: an account of the fishes (dughair), fish angles (Borsi), Monofilament fixed gill [22], fish species composition [23], occurrence of fish and net (Current jal) and Fish barrier (Thaga). The fresh non-fin fish [24], availability and consumer preference of samples were immediately chilled in ice on site and fixed small indigenous fishes [25], however, synthesis and with 10% buffered formalin upon arrival at the laboratory. analysis or assessments of fish biodiversity are limited, Identification of the samples was done based on 24°65 ° ° ° ° 89° 90 91 92 Nawabganj N 26° Bangladesh 24°55 25° Ganges Ram ° Godagari 24 24°45 Study site Krisnapur Nawabganj -Rajshahi Highway 23° IIndia Bangladesh Border 22° 24°35 Char Rajshahi city Bay of Bengal Khidirpur 21° 10 mi 24°25 10 km India Sardah Fig. 1: Map of the Padma (main tributary of the Ganges) River, northwestern Bangladesh. The dot circle shows the location of the sampling stations 329 World J. Zool., 7 (4): 328-337, 2012 Table 1: Fish diversity in the Padma River (lower part of the Ganges River), northwestern Bangladesh Order Family Scientific name English name Local name Recorded maximum TL (cm) Availability Status Beloniforrmes Belonidae Xenentodon cancila Freshwater garfish Kakila, Kaikka 40.0 [45] TY, LM Clupeiformes Engraulidae Setipinna phasa Gangetic hairfin anchovy Phasa 40.0 [46] TYS Clupeidae Corica soborna Ganges river sprat Kachki, Gura mach 4.1 SL [47] TY Gonialosa manmina Ganges river gizzard shad Chapila 14.1 [48] R, SM Gudusia chapra Indian river shad Chapila, Khoira 20.0 [48] TY Cypriniformes Cobitidae Botia dario Bengal loach Rani, Bou mach 15.1 [48] VR EN B. lohachata Reticulate loach Rani, Bou mach, Bagha 11.0 SL [49] VR EN Lepidocephalus guntea Guntea loach Puiya, Gutum 15.0 [27] SM Somileptus gongota Gongota loach Poia, Puiya 13.0 [48] VR Cyprinidae Amblypharyngodon mola Mola carplet Mola, Moa 20.0 [50] TYL A. microlepis Indian carplet Mola 10.0 [50] R Aspidoparia jaya Jaya Pioli, Jaya 15.0 [27] R A. morar Aspidoparia Morari 17.5 [27] TYL Catla catla Catla Katla, Katol 182.0 [50] R Cirrhinus cirrhosus Mrigal carp Mrigal, Mirka 100.0 SL [51] TYS C. reba Reba carp Raikhor, Reba 30.0 [50] TYS VU Devario devario Sind danio Banspata 10.0 [27] R Labeo bata Bata Bata 61.0 [27] TYS EN L. boga Boga labeo Bhangon, Bhangon buta 30.0 [27] TYS CE L. calbasu Orange fin labeo Kalbaus 90.0 [50] R EN L. nandina Nandi labeo Nandina 81.2 SL [48] R CE L. rohita Roho labeo Rui, Rohu 200.0 [52] R Laubuca laubuca Indian glass barb Chela 17.0 [53] TYS EN Osteobrama cotio cotio Cotio Dhela 15.0 [50] VR EN Puntius chola Swamp barb Chola punti 15.0 [53] TYS P. conchonius Rosy barb Kanchan punti 14 [27] TYS P. sarana Olive barb Sar Punti