331409 Finalreport India Fish
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PROJECT REPORT 3 3 1 4 0 9 A Case Study from the Ashambu Hills Landscape Southern Kerala, India (May 2009 - October 2010) By Robin Kurian Abraham*, R. Rajesh & Nachiket Kelkar * T.C. 11/1123, YMR Jn., Nanthencode Thiruvananthapuram, Kerala, India 695 003 email: [email protected] Disclaimer The information presented herein this report represents unpublished data and is thus not permitted for distribution beyond official circulation. The images and maps provided herein are the copyright property of Robin Kurian Abraham (and colleagues) and cannot be reproduced or distributed in any form without prior written permission from the copyright holder/s. Cover photographs Front: A collage of Protected Areas in the Ashambu Hills; fish species in the image is Bhavania australis Back: Top Left: climbing the Vamanapuram River; Bottom Right: at the headwaters of the Karamana River All Photo Credits: Robin Kurian Abraham, unless where mentioned Project Members .............................................................................. 4 Summary .......................................................................................... 5 Introduction ...................................................................................... 5 Project Aims ...................................................................................... 7 Methods ............................................................................................ 7 Study Area ....................................................................................... 7 Data collection and compilation ............................................................ 8 Preparing a preliminary checklist ..................................................... 8 Sampling freshwater fishes: species occurrence................................... 8 Ecological and anthropogenic covariates influencing freshwater fish communities ........................................... 9 Stakeholder awareness and perception: assessing opportunities for conservation ........................................... 9 Data analysis ..................................................................................... 9 Estimating species richness under imperfect detection ......................... 9 Relationship of species richness with ecological and anthropogenic covariates ....................................................... 12 Describing threats to fish species ................................................... 12 Results ............................................................................................. 12 Discussion: Conservation implications .......................................... 13 Conservation Recommendations .................................................. 16 Conclusion ...................................................................................... 19 Tables .............................................................................................. 25 References ...................................................................................... 30 Acknowledgements ....................................................................... 35 Appendices ..................................................................................... 36 Do Protected Areas of India’s Western Ghats conserve fish diversity? Project Members Robin Kurian Abraham R. Rajesh Nachiket Kelkar Occupation: Conservation Occupation: Fisherman Occupation: Wildlife Ecologist Biologist Project Role: Project Role: Field Expert & Project Role: Data Analyst Principal Investigator Assistant & Logistics Support Robin’s interest in Rajesh alias Reji, a forest Nachiket’s interest in freshwater fishes has tracker and fisherman par aquatic systems have stimulated his work excellence, has explored led him to study the on this group. While the wilderness of the biodiversity of rivers in concerned about their Ashambu Hills landscape, the Gangetic floodplains conservation, his main for work and for bread. and hills streams of interests are in freshwater His detailed knowledge the Western Ghats, the fish biogeography, of local ecology, estuarine lake of Chilika ecology, evolution & wild animals & fishes and the coral reefs of the behavior essentially make him Lakshadweep Islands. the project’s sampling compass. 4 Do Protected Areas of India’s Western Ghats conserve fish diversity? Do Protected Areas of India’s Western Ghats conserve fish diversity? Robin Kurian Abraham, R. Rajesh & Nachiket Kelkar Summary errestrial Protected Areas (PAs) designed to preserve charismatic species, have been recently challenged in their efficiency in conserving obscure species that are not often conservation priority. TIn this study in India’s Western Ghats, a biodiversity hotspot, we aimed to assess effectiveness of PAs in conserving freshwater fishes in the Ashambu Hills landscape in Kerala. We compared sites inside and outside PAs for fish species richness and identified covariates influencing them. We obtained a total of 60 species, including regional endemics, a potentially novel species and four range extensions. Higher numbers of fish species endemic to the Western Ghats were recorded in the mid-elevation zones of Protected Areas, than adjacent unprotected areas. The biased distribution of PAs towards higher altitudes and inaccessible localities may explain the greater endemism of hill stream fish species. Magnitude of threats to freshwater fish habitats was much higher in unprotected areas. But some threats were also present inside protected areas, clearly pointing to the lack of appropriate legislation, monitoring and enforcement for freshwater fish conservation. Despite being educated and aware of threats faced by freshwater systems, local people were overall passive to destructive, illegal practices such as dynamite- fishing and sand-mining. These issues prevailed in the human dominated landscapes outside PAs. Our study stresses the importance of PAs in conserving threatened and endemic hill-stream fishes of the Western Ghats. Effective conservation would require a landscape-level approach to freshwater fish conservation with fundamental changes in attitudes of all stakeholders and also changes in the existing legislation for conservation, along with strictly curbing any activities destructive to river ecology. It is of utmost importance to maintain intact freshwater habitats that exist in PAs. Introduction lobally, freshwater ecosystems are the most river conservation, restoration and management. Gseverely affected due to human development Water abstraction and pollution, degradation of and economic activities (Richter et al. 2003, freshwater habitats, overexploitation for food and Collen et al. 2008, Vörösmarty et al. 2010). The the aquarium trade, modification of flow regimes anthropogenic pressure on freshwater resources and sediment fluxes by dams and irrigation is extreme, and has led to critical endangerment projects, and introduced invasive species are the of freshwater biodiversity at both global and major threats to freshwater fishes today (Duncan regional scales (Allan & Flecker 1993, Richter et al. & Lockwood 2001, Cowx 2002, Almeida et al. 2002, 2003, Dudgeon et al. 2005). Conserving freshwater Dudgeon 2005). fish diversity and abundance for their ecological Freshwater Protected Areas (PAs) have been function and economic value is a significant part of proposed as a management solution for conserving 5 Do Protected Areas of India’s Western Ghats conserve fish diversity? both freshwater biodiversity and hydrological al. 2005). Apart from critical hydrological services, services (Keith 2000, Saunders et al. 2002, Crivelli they are also highly important for biodiversity 2002, Abell et al. 2007, Suski & Cooke 2007). However, conservation, with a very high endemism of flora the means with which freshwater conservation and fauna (Myers et al. 2000). In the Southern has been afforded is predominantly through Western Ghats, PA coverage extends from the existing terrestrial PA networks. Studies report inundated forested catchment areas of dams at mid- that this measure has been largely inadequate elevations built across many west-flowing rivers, to for freshwater systems (see Herbert et al. 2009). high-altitude, inaccessible landscapes at the crest Selection of terrestrial PAs is mostly biased towards of the Western Ghats. The inherent inaccessibility relatively inaccessible landscapes and difficult of the landscape has been a major factor in the terrain, often at higher elevations (Joppa & Pfaff declaration and sustenance of these areas as PAs. 2009). Such PAs naturally would not represent the As with plants, invertebrates and vertebrates, longitudinal dimension of river systems in entirety freshwater fish diversity in the Western Ghats ranks (Nel et al. 2009). Therefore, existing PAs may not be high, with around 290 species and a high degree fully effective in protecting freshwater fish diversity of endemism (>45%) (Myers et al. 2000, Daniels across riverine landscapes (Maitland 1995, Keith 2002). However, baseline information on taxonomy 2000, Crivelli et al. 2002). and distribution of the region’s fish fauna needs to Adequate spatial representation of river systems be well-documented (Raghavan et al. 2007) and in protected area networks has been proposed to is, at present, fragmented or inconsistent. Despite offset threats to freshwater ecosystem services, the rich diversity, there are few studies that have fish resources and biodiversity (Nel et al. 2007, quantitatively assessed impacts of anthropogenic