Ann.M. R. Bangladesh Islam, M. Das, Agric. M. (2018) N. Mondal 22 (1) and : 95-105 G. M. Mostakim ISSN 1025-482X (Print)95 2521-5477 (Online) STATUS OF FISH SPECIES DIVERSITY IN GHAGHAT RIVER IN NORTHERN BANGLADESH M. R. Islam1*, M. Das1, M. N. Mondal2 and G. M. Mostakim3 Abstract Fish species diversity and it’s conservation status of Ghaghat river in northern region of Bangladesh was investigated by field sampling using a taxonomic guide, FishBase data and International Union for Conservation of Nature (IUCN) conservation index. The study revealed that a total of 55 species of fishes belonging to 45 genera, 22 families and 9 orders were found in the river. Among the identified fish orders, Cypriniformes was the highest diverse group with 34% species abundance followed by Siluriformes and Perciformes with 24% each. On the other hand, fishes under the orders Beloniformes, Decapoda, and Tetradontiformes were the least abundant (2%). Fish species diversity was found prominent during the monsoon. Based on IUCN conservation index 6(11%), 10(18%) and 7(13%) species in Ghaghat river were identified as critically endangered, endangered and vulnerable respectively. A total 14 types of fishing gear under 8 major groups were found to operate in the studied river, which included some banned gears like gill net and seine net. An effective conservation strategy needs to be developed to stop indiscriminate fishing and to conserve the fish biodiversity in Ghaghat river. Keywords: Fish, biodiversity, ghaghat river, conservation. Introduction barrages, pollution, using of banned fishing gears fish biodiversity is declining (Rahman Bangladesh is blessed with a large number et al., 2016). of rivers including tributaries of about 700 covering a total length of about 24,140 km The Ghaghat river (236 km long) is a (Rashid, 1991). Total fish production of tributary of Tista river, originated at Jaldhaka the country was 38.78 lakh MT in 2015-16, in Nilphamari district and after passing where the contribution of inland open water through Gaibandha town (few km north of fisheries is 4.60% (1.78 lakh MT) (DoF, Fulchhari Ghat) joins to the Brahmaputra 2017). The open water bodies are habitat of river (Banglapedia, 2012). In the northern 265 freshwater fish species (Rahman, 2005). part of Bangladesh the Ghaghat river is an Therefore, rivers have rich fish biodiversity important inland open water-body and a vital (Rahman et al., 2015). Unfortunately, due to breeding ground of many freshwater fish overfishing, indiscriminate harvesting of fry species, therefore, plays a significant role in and fingerlings, construction of roads and the fisheries sector of the country. However, 1Department of Aquaculture, Bangabandhu Sheikh Mujibur Rahman Agricultural University, Gazipur 1706, 2Department of Fisheries Management, Bangabandhu Sheikh Mujibur Rahman Agricultural University, Gazipur 1706, 3Department of Fisheries Biology and Aquatic Environment, Bangabandhu Sheikh Mujibur Rahman Agricultural University, Gazipur 1706, Bangladesh.*Corresponding author: [email protected] 96 Status of Fish Species Diversity in Ghaghat River in Northern Bangladesh fish catch and species diversity in most of the Sample collection river are declining day by day. There is no Sampling was carried out at all the stations previous research on fish biodiversity, fishing during day and night with the help of gears, fish availability of Ghaghat river, which professional fishermen covering pre-monsoon consequently would limit the establishment of (Mid April-Mid June), monsoon (Mid June- management and biodiversity conservation Mid August) and post-monsoon (Mid August- strategies. Therefore, the present study was conducted to gather fish biodiversity Mid October) period in the year 2017. Fish information and baseline data to reveal the samples were also collected from local fish present status of the Ghaghat river. landing centers and markets. Fishes were caught by means of traditional fishing gears Materials and Methods like cast net (jhaki jal), seine net (ber jal), lift Study area net (dharmo jal), hook (borshi) and traditional The investigation was carried out in four fish trap locally called bair. Twenty throw sampling sites (station 1 to 4) in the main river and twenty hauls were considered by cast net basin (Fig. 1) for recording available fish species and lift net in each time during the sampling. diversity. The prime criteria for site selections Fishing traps were set at the stations during the were higher fishing intensity and the presence late afternoon and kept for overnight to check of a good number of fishermen in the locality. the trapped species in the following morning. Fig. 1. Map of the study area (Left) with satellite image (Right) of Ghaghat river showing four sampling sites. M. R. Islam, M. Das, M. N. Mondal and G. M. Mostakim 97 The collected specimens were identified Results and Discussion primarily during sampling time. Unidentified Fishing gear samples were preserved in the plastic jar with Different types of fishing gear operated in 10% formalin and brought to the laboratory Ghaghat river, major fish species caught and of Bangabandhu Sheikh Mujibur Rahman the number of people engaged to operating the gears was recorded during the study period Agricultural University, Gazipur, Bangladesh (Table 1). A total 14 types of fishing gear were to perform species identification. recorded under 8 major groups such as gill net (current jal, fash jal), seine net (ber jal), cast Identification of fish sample net (jhaki jal), lift net (dharma jal, khora jal), Fish samples were identified on the basis of push net (thela jal, moiya jal), trap (bar, dheal, morphometric and meristic characteristics. polo), hook and line (chip borsh, wheel borsh), The collected specimens were identified up and wounding gear (koch). Jhakijal, ber jal, dharma jal, darki, dheal, and chip borshi were to species level according to the taxonomic found mostly operated fishing gears in the guide of Rahman (2005) and Talwar et al. study area. (1991). In addition, FishBase (Froese and Pauly, 2000) was used to remove taxonomy The use of banned fishing gears was one of the discrepancies. main reasons of loss of biodiversity around the world (Harrison and Stiassny, 1999; Allan Identification of fishing gear et al., 2005; Dudgeon et al., 2006). According to a study of Afrose and Ahmed (2016), over Fishing gear including major species caught exploitation is responsible for 42% of fish by the particular gear was surveyed by diversity loss in the Brahmaputra river of Participatory Rural Appraisal (PRA) through Bangladesh. Indiscriminate fishing by gill net, Focus Group Discussion (FGD) and Key seine net even in the breeding season is also Informant Interview (KII) with the fishermen responsible for the decline in fish catch and in the sampling sites. species composition. Rahman et al. (2015) found that fish diversity is declining in a river Determination of threatened and non- of Bangladesh due to overfishing and use threatened fish status of non-selective fishing gears like seine net, The present status of threatened and non- gill net and push net. Some gears with small threatened fish species was determined by mesh size such as: seine net, cast net, push using the Red Book of Threatened Fishes of net, lift net could act as non-selective for the Bangladesh (IUCN, 2015). certain group of fishes, which could lead to a huge quantity of immature fish being caught Data analysis (Adebiyi, 1998). All the collected data were carefully checked Fish species diversity recorded and analyzed using Microsoft Excel and presented in both graphical and A total 55 species of fishes were recorded tabular form. in Ghaghat river during the study belonging 98 Status of Fish Species Diversity in Ghaghat River in Northern Bangladesh Table 1. Different types of fishing gears recorded for fishing in Ghaghat river Operational fishermen Gear type Local name Fish species caught (No.) Gill net Current jal Mystus vittatus, Puntius ticto, Channa punctatus, 1-2 Eutropiichthys murius Fash jal Mystus bleekery, Tenualosa ilisha, Sperata aor 1-2 Seine net Ber jal Amblypharyngodon mola, Laubuca laubuca, Puntius ticto, Trichogaster fasciata, Labeo rohita, 8-10 Catla catla Cast net Mut jal, Jhaki jal Puntius ticto, Trichogaster fasciata, Labeo bata, 1 Labeo rohita Lift net Dharma jal Puntius ticto, Mystus bleekery, Amblypharyngodon 1-2 mola, Osteobrama cotio Khara jal Labeo rohita, Catla catla, Mystus bleekery, 1-2 Puntius ticto, Wallago attu Push net Thela jal Mystus bleekery , Puntius ticto, Rasbora rasbora, 1 Channa punctatus, Glossogobius giuris Moiya jal Small fishes 1-2 Darki Trap Puntius ticto, Channa punctatus, Heteropneustes fossilis, Clarias batrachus, Mastacembelus 1 armatus Dheal Puntius ticto, Channa punctatus, Heteropneustes fossilis, Clarias batrachus, Mastacembelus 1 armatus Polo Mystus bleekery, Puntius ticto, Channa punctatus, 1 Glossogobius giuris Hook and Chip borshi Puntius ticto, Wallago attu, Mystus bleekery, 1 line Channa punctatus, Labeo rohita Wheel borshi Puntius ticto, Wallago attu, Mystus bleekery, 1 Channa punctatus, Labeo rohita Wounding Koch Channa punctatus, Channa striatus 1 to 9 orders, 22 families and 45 genera During the study, a great variety of fish species (Table 2). The most dominant fish order were recorded from 22 diversified families. was Cypriniformes (34%) contributing Among those Cyprinidae was the most species 19 fish species in 13 genera followed by rich family accounting for 29.09% of the total Siluriformes and Perciformes both consist number of species recorded with 10 diversified of 24% of the species biodiversity (Fig. 2). genera (Figure 3). Other noticeable families The other orders were Synbranchiformes, were Bagridae (9.09% species), Channidae Osteoglossiformes, Clupeiformes consisted of (7.27 % species), Cobitidae, Mastacembilidae, 5, 4 and 3%, respectively of the total species Osphronemidae and Schilbeidae (5.45% caught. The rest 3 orders were: Beloniformes, species each). The lowest percentage of Tetradontiformes, and Decapoda each had 2% fish (1.82%) were recorded from the family species composition. Anabantidae, Belonidae, Cichlidae, Clariidae, M. R. Islam, M.