International Journal of Fisheries and Aquatic Studies 2015; 2(6): 11-18 ISSN: 2347-5129 Distribution pattern, threatened status and (ICV-Poland) Impact Value: 5.62 (GIF) Impact Factor: 0.352 conservation measures of fishes with relation to water IJFAS 2015; 2(6): 11-18 © 2015 IJFAS quality and habitat characteristics of Bhavanisagar www.fisheriesjournal.com Received: 22-04-2015 Reservoir, Tamil Nadu Accepted: 20-05-2015 M. Raja M. Raja, R. Ramkumar, M. Kavitha, P. Perumal Department of Biotechnology, Periyar University, Periyar Palkalai Nagar, Salem 636 011, Abstract Tamil Nadu, India. This study documents the water quality, habitat characteristics and freshwater fish diversity of Bhavanisagar Reservoir, Tamil Nadu. We recorded 52 species represented by 8 orders, 13 families and R. Ramkumar 38 genera. The Cyprinid family was found to be dominant in the present study. Various diversity indices Department of Biotechnology, have been used to assess the fish diversity. The highest species diversity was found out in Bhavanisagar Periyar University, Periyar Dam (S1) and lowest species diversity was recorded in Aapakkudal (S7) sites. Fish diversity was also Palkalai Nagar, Salem 636 011, correlated with physicochemical variables and habitat characteristics. Among 52 fish species collected Tamil Nadu, India. from 10 study sites of the upstream/ downstream areas of Bhavanisagar reservoir, of which 2 species (4%) were found to be critically endangered, 41 species were least concerned (79%), 5 species were near M. Kavitha threatened (9%) and 4 species were in vulnerable category (8%). The threat status of fishes found in the Department of Biotechnology, Bhavanisagar reservoir strongly suggests the need for effective conservation measures to conserve the Periyar University, Periyar Palkalai Nagar, Salem 636 011, fish species richness. Tamil Nadu, India. Keywords: Bhavanisagar reservoir, Fish fauna, Water quality, Habitat characteristics, Species diversity P. Perumal indices. Department of Biotechnology, Periyar University, Periyar 1. Introduction Palkalai Nagar, Salem 636 011, Fishes exhibit enormous diversity in their morphology, habitats they occupy, and in their Tamil Nadu, India. [1] biology . Hence, biodiversity and conservation are regarded as the major issues enabling [2] sustainable use of natural resources . It seems necessary and today’s most urgent and significant need to protect ichthyofaunal diversity [3] in their natural habitat. Over the last century, river ecosystems have suffered from intense human intervention resulted in habitat loss and degradation and as a consequence, many fish species have become highly endangered, [4] particularly in rivers where heavy demand is placed on fresh waters . The main causes are [5] habitat destruction, defragmentation, industries, private use pollution stress and global climate change impacts [6]. Freshwater fish fauna is one of the most threatened taxonomic groups due to high sensitivity to qualitative alteration of aquatic environment [7]. Fishes are often used as bio-indicator for the assessment of water quality or increasing pollution potential [8] [9] . The fish diversity and associated habitats management are a great challenge . As habitat degradation continues to accelerate on a global scale, maintenance of species richness and biodiversity has become a central issue of conservation biology [10, 11, 12, 13]. Inland aquatic systems are crucial for the conservation of local and global biodiversity [14]. In fact, there is a great diversity in the form and function of these aquatic systems, presenting a wide range of habitats [14, 15, 16]. The influence of habitat heterogeneity on species richness is well appreciated [17, 18] , but the relationship between habitat structural complexity and density of species exhibiting different ecological characteristics has received comparatively little attention. The freshwater ichthyofauna diversity of Tamil Nadu was reported by various researchers [19, 20, 21, Correspondence: 22]. The fish diversity of Cauvery river system have been reported [23, 24] including fish diversity P. Perumal [25] Prof & Head, Department of of Grand Anicut, Tiruchirappalli. Recently, studied the diversity, distribution, threats and Biotechnology, Periyar conservation action of fish fauna in Chinnar, Krishnagiri and Stanley reservoirs of Tamil University, Periyar Palkalai Nadu. Nagar, Salem 636 011, Tamil The Rivers and tanks have faced major alterations in the recent years due to increasing Nadu, India. urbanization, industrialization and various recreational activities [26]. Reassessment of the fish ~ 11 ~ International Journal of Fisheries and Aquatic Studies fauna and identifying the threats, so as to build baseline together into the Bhavanisagar reservoir after which it information for possible conservation action plans are thus a becomes the Bhavani River, is a tributary of the Cauvery (Fig. priority [27]. However, the fish diversity in Bhavanisagar 1). The dam feeds the Lower Bhavani Project Canal and is the reservoir of Tamil Nadu in particular is lacking; no attempt second largest dam in Tamil Nadu. The elevation of the river was made to analyse the habitat, physico-chemical basin ranges from 300 m a.m.s.l. on the plains to 2600 characteristics and fish fauna in detail. Hence, the present ma.m.s.l. on the Nilgris plateau. Accordingly, the annual study was aimed to focus on these measures. rainfall varies from 700 mm on the lowlands to nearly 3000 mm in the hills. Ten study sites were selected from 2. Materials and Methods Bhavanisagar Dam (S1) to Bhavani Kooduthurai (S10) with a 2.1 Study sites: Bhavani, the second largest river in Tamil distance of 10 Km interval on the basis of habitat Nadu, originates from Silent Valley National Park in Palakkad heterogeneity (pools, riffles, run and backwaters), water district of Kerala and flows into Tamil Nadu, covering a quality, depth and disturbances. From the selected sites, distance of 217 km before confluence with Cauvery River at samplings during the period October 2013 to September 2014 Bhavani town. Bhavanisagar Dam and Reservoir also called as from a 100-150 m reach in all the sites and all the observations Lower Bhavani Dam, is located on the Bhavani River in Erode were made during day lights. district, Tamil Nadu. The Bhavani and Moyar rivers flows Fig 1: List of study sites in Bhavanisagar Reservoir 2.2 Sampling methods: Habitat parameters were taken using California Academy of Sciences [34, 35] and fish status was the habitat inventory methods [28, 29]. Water samples were checked in IUCN red list [36]. Fish species diversity was collected in 2L plastic containers and brought to the laboratory subjected to diversity analysis using different indices like for further analysis. Air and water temperatures were measured species richness (S = number of species); Shannon–Weaver at sampling time using mercury-in-glass thermometer, pH was Information Index [37]; Simpson Dominance Index [38]; Species estimated using standardized pocket pH meter and the Dominance Index [39]; Pielous Evenness [40], Principal conductivity was measured using the conductivity meter, Component Analysis and dendrogram analysis were performed dissolved oxygen was estimated by [30] method. The total using statistical packages PAST [41]. dissolved solids, alkalinity, total hardness, BOD and COD were analyzed by [31] methods. All the essential data like place 3. Results and Discussion of collection, date, habitat characters were recorded. Fish A total of 52 species representing by 8 orders, 13 families and samples were collected with the help of gill, cast and drag nets. 38 genera were recorded during the present study. Five to ten specimens of each species were collected for Cypriniformes was the dominant group among all with 57.7% identification while the rest were released back into the water. of the assemblage composition followed by Siluriformes with The specimens were lively photographed with Canon 1100 19.2%, Perciformes with 13.5% and other orders namely Digital SLR camera and were preserved in 4% buffered Osteoglossiformes, Anguliformes, Mugiliformes, formaldehyde solution. The collected specimens were Cyprinodontiformes, and Synbranchiformes forming 1.9% transported to Department of Biotechnology-Cum-Laboratory each (Table 1). The distribution pattern fish species between Museum of the Periyar University Museum of Natural History, the selected sites are summarized (Table 2). Salem, Tamil Nadu, India and assigned the specimen Most of Cyprinids such as Salmophasia bacaila, Salmophasia catalogue numbers (PUMNH 201-252). The species acinaces, Barilius gatensis, Barilius bendelisis, Devario identification and confirmation were carried out using aequipinnatus, Rasbora cauverii, Systomus sarana, Dawkinsia available literature [32, 33]. The valid species nomenclatural filamentosa, Puntius chola, Puntius dorsalis, Pethia ticto, names were adopted as per the Catalogue of Fishes of the Pethia conchonius, Labeo fimbriatus, Labeo rohita, Garra ~ 12 ~ International Journal of Fisheries and Aquatic Studies Table 1: Fish species recorded from the upstream/downstream areas of Bhavanisagar reservoir, Tamil Nadu, India. S. No Order Family Genera Species Percentage (%) 1 Osteoglossiformes Notopteridae 1 1 1.92 2 Anguliformes Anguillidae 1 1 1.92 3 Cypriniformes Cyprinidae 21 29 55.8 Cobitidae 1 1 1.92 4 Siluriformes Bagridae 4 7 13.5 Pangasiidae 1 1 1.92 Clariidae 2 2 3.84 5 Mugiliformes Belonidae 1 1 1.92 6 Cyprinodontiformes Cyprinodontidae 1