Do Protected Areas of India’s Western Ghats conserve fish diversity?

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PROJECT REPORT

331409

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: robinabrahamf50@gmail.com


Disclaimer The information presented herein this report represents unpublished data and is thus not permitted for distribution beyond official circulation.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

4

Robin Kurian Abraham Occupation: Conservation Ecologist

R. Rajesh Occupation: Fisherman

Nachiket Kelkar Occupation: Wildlife Biologist

Project Role: Principal Investigator

Project Role: Field Expert & Assistant

Project Role: Data Analyst & Logistics Support

Robin’s interest in freshwater fishes has stimulated his work on this group. While concerned about their conservation, his main interests are in freshwater fish biogeography, ecology, evolution & behavior

Rajesh alias Reji, a forest tracker and fisherman par excellence, has explored the wilderness of the Ashambu Hills landscape, for work and for bread. His detailed knowledge of local ecology, wild animals & fishes essentially make him the project’s sampling compass.

Nachiket’s interest in aquatic systems have led him to study the biodiversity of rivers in the Gangetic floodplains and hills streams of the Western Ghats, the estuarine lake of Chilika and the coral reefs of the Lakshadweep Islands.


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

T

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. In 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 dynamitefishing 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

G

lobally, freshwater ecosystems are the most severely affected due to human development and economic activities (Richter et al. 2003, Collen et al. 2008, Vörösmarty et al. 2010). The anthropogenic pressure on freshwater resources is extreme, and has led to critical endangerment of freshwater biodiversity at both global and regional scales (Allan & Flecker 1993, Richter et al. 2003, Dudgeon et al. 2005). Conserving freshwater fish diversity and abundance for their ecological function and economic value is a significant part of

river conservation, restoration and management. Water abstraction and pollution, degradation of freshwater habitats, overexploitation for food and the aquarium trade, modification of flow regimes and sediment fluxes by dams and irrigation projects, and introduced invasive species are the major threats to freshwater fishes today (Duncan & Lockwood 2001, Cowx 2002, Almeida et al. 2002, Dudgeon 2005). Freshwater Protected Areas (PAs) have been proposed as a management solution for conserving 5


Do Protected Areas of India’s Western Ghats conserve fish diversity?

both freshwater biodiversity and hydrological services (Keith 2000, Saunders et al. 2002, Crivelli 2002, Abell et al. 2007, Suski & Cooke 2007). However, the means with which freshwater conservation has been afforded is predominantly through existing terrestrial PA networks. Studies report that this measure has been largely inadequate for freshwater systems (see Herbert et al. 2009). Selection of terrestrial PAs is mostly biased towards relatively inaccessible landscapes and difficult terrain, often at higher elevations (Joppa & Pfaff 2009). Such PAs naturally would not represent the longitudinal dimension of river systems in entirety (Nel et al. 2009). Therefore, existing PAs may not be fully effective in protecting freshwater fish diversity across riverine landscapes (Maitland 1995, Keith 2000, Crivelli et al. 2002). Adequate spatial representation of river systems in protected area networks has been proposed to offset threats to freshwater ecosystem services, fish resources and biodiversity (Nel et al. 2007, 2009). However, in human-dominated landscapes in developing countries, excessive pressures on natural resources directly conflict with the legal inviolateness of more accessible PAs. Thus, landscape-scale conservation of easy and open access systems such as rivers and wetlands can seriously overlap with diverse stakeholder needs dependent on terrestrial and freshwater habitats (Dudgeon et al. 2005). Further, the focus of conservation in terrestrial PAs has predominantly been on charismatic species such as mammals and birds. Recent studies have shown that protected areas designed primarily to conserve such species are not adequate for many ‘lesser taxa’ or obscure species groups (Rodrigues et. al. 2004). Protected areas have been established in India’s Western Ghats, a biodiversity hotspot, with positive results for charismatic species of mammals and birds (Bawa et al. 2007). Yet, a recent study has indicated that this conservation model may not be adequate for amphibian conservation (Vasudevan et. al. 2006). The Western Ghats mountain range, straddling the west coast of India is the point of origin for several streams that form the headwaters of many important rivers, the main source of freshwater to the plains of peninsular India (Krishnaswamy et 6

al. 2005). Apart from critical hydrological services, they are also highly important for biodiversity conservation, with a very high endemism of flora and fauna (Myers et al. 2000). In the Southern Western Ghats, PA coverage extends from the inundated forested catchment areas of dams at midelevations built across many west-flowing rivers, to high-altitude, inaccessible landscapes at the crest of the Western Ghats. The inherent inaccessibility of the landscape has been a major factor in the declaration and sustenance of these areas as PAs. As with plants, invertebrates and vertebrates, freshwater fish diversity in the Western Ghats ranks high, with around 290 species and a high degree of endemism (>45%) (Myers et al. 2000, Daniels 2002). However, baseline information on taxonomy and distribution of the region’s fish fauna needs to be well-documented (Raghavan et al. 2007) and is, at present, fragmented or inconsistent. Despite the rich diversity, there are few studies that have quantitatively assessed impacts of anthropogenic pressures and land management regimes on freshwater fish assemblages (although see Bhat 2003, 2004, Sreekantha et al. 2007, Raghavan et al. 2008, Johnson & Arunachalam 2009). There have been no studies on how the existing PA network in the Western Ghats affects conservation of freshwater fish species. We investigate through this study the importance of existing Protected Areas for fish conservation in the Ashambu Hills landscape of the Southern Western Ghats. This region is very rich in fish species diversity and endemism, and also has some degree of faunal similarities with Sri Lanka (Bossyut et al. 2004). We compare fish species richness across different sites within PAs and in unprotected (NonPA) areas in this landscape (for similar approaches see Curtis et al. 1998, Corbacho & Sanchez 2001, Anand et al. 2010). It is a priori expected that fish species diversity will be higher in the larger plains’ rivers than in the hill streams (Bhat & Magurran 2006). Studies have shown that increasing trophic levels and species diversity are supported with increasing stream order and decreasing altitude (Vannote et al. 1980). We also expect higher richness of species endemic to Western Ghats (referred to hereafter as Western Ghats’ endemics) within PAs (Bergl et al. 2007) due to factors such as geographical isolation


Do Protected Areas of India’s Western Ghats conserve fish diversity?

Figure1. Map showing the Ashambu hills landscape, Western Ghats, Kerala, India. The elevation and land-use gradient across the landscape with the existing protected area network is shown here. Sampling sites on each river are indicated

of river valleys and the associated specializations in the habits of these species (Daniels 2002, Dahanukar et al. 2004). It must be noted here that hill streams are mostly within the PA network, while the larger stream orders in the plains are largely non-protected, open access areas. Is this skewed nature of PA selection affecting fish diversity, distribution and ultimately their conservation? In other words, what are the implications of the existing framework of PA management for conserving endemism and species richness? To answer these questions we compared a range of sites with regards to freshwater fish species richness, across a land-use gradient comprising of PAs, rubber plantations, coconut plantations, mixed gardens, and rural or urban areas. A comprehensive checklist of freshwater fishes potentially found in the region has also been compiled based on the latest taxonomic updates and information. We recorded information on threats to conservation of freshwater fishes across this landscape, and assessed levels of awareness and perception of different stakeholders towards threats to conservation of freshwater fishes. Effects of various anthropological and ecological covariates on distribution of freshwater fishes in the region were also investigated.

Project Aims The specific objectives of our study were: 1. To assess distribution of fish diversity across different management regimes and identify threats to freshwater fish conservation 2. To investigate the effects of ecological and anthropogenic covariates on fish species richness and occurrence 3. To communicate findings of this project to stakeholders such as local communities, PA managers, NGOs and educational/research institutions to facilitate optimal conservation of fish resources in this landscape.

Methods Study Area Our study area comprised of five river basins within Kollam and Thiruvananthapuram districts of Kerala state, India. These west-flowing rivers (Kallada, Ithikkara, Vamanapuram, Karamana and Neyyar) are the main rivers within the Ashambu Hills landscape 7


Do Protected Areas of India’s Western Ghats conserve fish diversity?

in Kerala (Figure 1) (Basak et al. 1995, Biju et al. 2000). These hills are biogeographically unique, with many species of plants, amphibians and invertebrates unique to them even within the Western Ghats (Nair 1991). The Kerala part of these hills contains five protected areas including three wildlife sanctuaries (WLS) (Shendurney, Peppara and Neyyar) and two reserve forests (RF) (Kulathupuzha and Palode) and adjoins a tiger reserve. All these management zones are contiguous with a large forested region (the Kalakkad-Mundanthurai Tiger Reserve in Tamil Nadu state) which marks the southernmost point of the Western Ghats within India. Owing to its peculiar location and natural barriers (the Ariyankavu/ Shenkotta pass in the north, and the Palk Strait in the south between India and Sri Lanka), the landscape is a very unique biotope within the Western Ghats. With the exception of Ithikkara (origin at 240 m ASL), all other rivers originate at elevations beyond 1600 m ASL, in the Ashambu hill range running along the border of the Kerala and Tamil Nadu states (Basak et al. 1995). All these rivers rise from either a fully protected (WLS) area or from an area under partial protection (RF). They proceed westward to meet the Arabian Sea, passing through a similar land-use gradient (in respective order) with mainly rubber plantations, coconut plantations, mixed gardens and paddy cultivation to urban, semi-urban to rural areas. The Ithikkara and Vamanapuram rivers are without major dams; Neyyar and Kallada have one dam each, while Karamana has two.

Data collection and compilation Preparing a preliminary checklist Based on an exhaustive review of published literature, field guides, ecological studies, short notes and reports, taxonomic assessments and previous checklists from this or neighbouring regions (Silas 1951, Menon 1987, Jayaram 1991, 1994, Pethiyagoda 1994, Lal Tekriwal & Arunava Rao 1999, Sheeba 1999, Arunachalam 2000, Biju et al. 2000, Martin et al. 2000, Bhat 2003, Dahanukar et al. 2004, Easa & Shaji 2003, Thomas 2004, Raagam & Rema Devi 2004, Pethiyagoda & Kottelat 2004, Devi et al. 2005, Raghavan et al. 2007, 2008, 8

Johnson & Arunachalam 2009, Eschemeyer & Fong 2010) we prepared a preliminary checklist of fish species recorded from, or that may be potentially found in this region. This checklist had 105 fish species belonging to 59 genera in 23 families (see Appendix 2), and based on the taxonomic treatment provided by Eschmeyer & Fong (2010) with a few modifications based on Jayaram (1994). We also collected information about occurrence for many of the listed species by consultations with freshwater fish taxonomists (Biju Kumar, A., Daniels, R.J.R., Bhat, A., Shaji, C. P., Raghavan, R., Anvar Ali, P.H., Sheeba, S., Weerakoon, D., Dahanukar, N. – Pers. Comm).

Sampling freshwater fishes: species occurrence We systematically selected 20 sampling locations across the five rivers (Table 1), with equal numbers of sites in the highlands, midlands and lowlands (Figure 1). Each river had three to five uniformly spaced sampling points within the elevation range of 10 to 200 m, and represented the four broad land-use types (protected area / reserve forest, rubber plantation, coconut plantation / mixed-gardens, semi-urban / urban area). We chose to restrict sampling within this elevation range to compare similar sites within protected and non-protected areas. Sites in higher altitudes were opportunistically surveyed to record species with restricted distributions. We carried out fish surveys and identification through non-destructive sampling by using methods of sampling suited to nature of the river course, stream order, flow, presence of aquatic vegetation and local human disturbance. At each site we used cast-nets till local species saturation was obtained; and visual surveys to record fish species presence. At sites with calm flow and uniform depth, gill-nets were deployed to catch mobile fish species. Hooks and lines were used to catch predatory fish species such as eels (Anguilla spp.), catfishes and snakeheads (Channa spp.). Fish catches found in nets of fishermen at certain sites were also opportunistically collected, wherever possible. Fish were identified using taxonomic keys and photographic identification from various field guides. We followed the taxonomic treatment provided by Eschmeyer and Fong (2010) for species


Do Protected Areas of India’s Western Ghats conserve fish diversity?

identification. Owing to continued bad weather for over 3 months during the prime sampling period (torrential rains and resulting flash floods and swift flow of the rivers), we could not replicate sampling at any of these sites.

Ecological and anthropogenic covariates influencing freshwater fish communities Along with sampling fishes, we measured many explanatory variables of ecological and anthropogenic covariates (Table 2). Selected variables were based on previous literature (Jowett & Richardson 1996, Freeman et al. 2001, Cowx 2002, Bhat 2003, 2004, 2005, Chakarabarty & Das 2006, Humpl & Pivnicka 2006, Habit et al. 2006, Sreekantha et al. 2007) on their ecological importance to fishes as well as in relation to known threats in the landscape. Local and landscape-level threats to freshwater habitats and fish species were also recorded (Table 3) and mapped using a GIS platform. We digitized spatial polygons to classify land-use category within a GIS, using ground data. This categorization was used to represent the broad land-use characteristic of that area. We identified important land-use changes for individual river basins in the last 20 years using recent satellite imagery (available in 2009) and topographical maps (at 1:25,000 cm resolution, published in 1989). Association between elevation class and land-use type was tested using a Cramer’s V test for contingency tables. A threat-index based on ranked information on locally observed threats was assigned to each site. Local and landscapelevel threats were described at various sites in the region to serve as a guide for policy makers and PA managers.

Stakeholder awareness and perception: assessing opportunities for conservation Informal discussions and semi-structured interviews with a variety of stakeholders of the rivers of the landscape were carried out to understand awareness of ecology and conservation threats and the general perception towards fish species and fish resources. Through the interview surveys we collected data on presence and perception of

specific threats in past and present experience, and future predictions. Threats were enlisted using the IUCN Red List Guidelines (IUCN 2010a, 2010b). (Robin Kurian Abraham is currently involved in status assessment of several fish species of the Western Ghats for the IUCN Red List Assessment, 2010.) We also compiled a review of all environmental and biodiversity conservation related acts in India to identify legal framework for conservation of freshwater fish (see Singh 1998, Government of India 2010).

Data analysis Estimating species richness under imperfect detection ‘Imperfect detection’ refers to the capture process by which species sampled at a site are only a fraction of the total number of species present at that site. The heterogeneous representation of species in sampling could be due to individual species’ differences in relation to ecological and observation-related factors (Royle & Dorazio 2008). To address this problem of imperfect detectability of fish species captured, we used a Bayesian hierarchical modeling approach to estimate total species richness, given our sample data. Bayesian analysis allows us to incorporate uncertainty in parameter values by treating each parameter in models as a random variable based on some appropriate statistical distribution (Spiegelhalter et al. 2007). This is called a prior distribution and can be used to represent prior knowledge about model parameters (for example, occurrence probability of species) (Royle & Dorazio 2008). The Bayesian hierarchical model specifies the probabilistic process model that describes how the actual occurrence probabilities may potentially vary, and further an observational probability model for species detected from the actual data (samples). A procedure called data augmentation was used to represent the expected number of species that were actually never caught (Royle & Dorazio 2008). The augmented dataset represented the process model for occurrence probability as a binomial 9


Do Protected Areas of India’s Western Ghats conserve fish diversity?

Sampling for fishes in the Vamanapuram River inside a Protected Area © Vicky Lakshmanan

Cast-netting in the Ithikkara River (80m ASL) in a non-protected area

Interviewing a resident at the Ithikkara River © Nikhil James

Testing the water quality of the Neyyar River in a non-protected area

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Do Protected Areas of India’s Western Ghats conserve fish diversity?

Figure 2. Box Plot showing comparitive species richness of Western Ghats’ endemic fishes Rivers within PAs have higher species richness of Western Ghats’ endemic fish species than in unprotected areas

Figure 3. Species richness of Western Ghats’ endemic fishes with increasing elevation Log-log plot of Western Ghats’ endemic species richness in relation to elevation (in metres). Mid-elevation sites within Protected Areas have the most endemic species

Figure 4. Species richness was highest in intermediate stream-orders, in the mid-elevation areas

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Do Protected Areas of India’s Western Ghats conserve fish diversity?

random variable with ‘detection or non-detection’ outcomes from the sampled spatial unit(s). Spatial subsamples of species richness were used as replicates to derive the observation model for each land-use class (PA, Rubber plantation, Lowland agriculture), with detection probability drawn from a binomial distribution. This approach is analogous to estimation of closed populations based on sampled individuals (‘species’ in this case) with individual heterogeneity in detectability (Royle & Dorazio 2008). The numbers of species added with the data augmentation for each land-use class were based on information elicited from literature reviews that suggested occurrence of between 85 to 100 species from the area. Uniform prior distributions were used for occurrence and detection probability of species in the augmented dataset. We obtained posterior estimates of species richness for each ‘treatment’ by updating our data on fish species with prior expectations about species richness in the Bayesian model. These ‘corrected species richness’ values from protected areas (WLS, RF), rubber plantations and lowland agriculture areas were visually compared. They were also compared with ‘expected species richness’ values derived from published information on three broad-scale surveys of freshwater fishes across this region (Biju et al. 2000, Easa & Shaji 2003, Thomas 2004).

Relationship of species richness with ecological and anthropogenic covariates

We used generalized linear models (Poisson Regression) to investigate the relationship between fish species richness and explanatory variables (Table 2) using a stepwise variable selection procedure. We used the Akaike Information Criterion (AIC) for model selection.

Describing threats to fish species

Hierarchical cluster analysis was used to group different sites based on threat intensity values for a set of threat-related variables (Table 2). We looked for deviations from expected clusters, especially to see whether sites from PAs and non-PAs clustered together. A simple ranking procedure was used 12

on threat scores to enlist the best and worst sites in terms of conservation value, both within PAs and outside PAs. Maps describing land-use type, threats, freshwater fish occurrence and distribution, and ranked information for different sites and areas, were produced using GIS software ArcView™ GIS 3.3. All statistical analyses were conducted using the software R 2.10.1 (R Development Core Team 2010). The Bayesian analyses were conducted using both the software R® and WinBUGS (Spiegelhalter et al. 2007).

Results The total number of species found in the study was 60, belonging to 36 genera and 16 families (Appendix 1). Protected areas had higher species of Western Ghats endemic fishes than reserve forest or non-protected areas (Figure 2). PAs also had more ‘threatened’ species than in non-protected areas. There was a significant association between elevation class and protection status, with regards to species richness (Cramer’s V = 0.57121, p = 0.00008). Lowland agriculture sites had the highest estimated total species richness, followed by sites inside PAs, and sites in rubber plantations in the midlands had the lowest species richness (Table 3). However, expected richness values for these sites differed considerably, with PAs having the highest number of species (Table 3). Species richness increased with elevation to about 800 m and declined at higher elevations (Figure 3). Sites in PAs were mostly similar to each other in terms of presence and magnitude of local threats. But, many threatened fish species and even common species of commercial or ecological importance had higher relative abundance, or were recorded only inside PAs. The spatial coverage (areal extent) of rivers in PAs for midland areas (mean 29.04 km2, range 1.0 to 71.35 km2) was less than the coverage in unprotected midland areas (mean 48.27 km2, range 29.1 to 77.26 km2). Undammed rivers had hardly any spatial coverage of midland stretches in PAs (1 to 1.7 km2). Physical and chemical parameters were mostly similar between unprotected and protected areas, except nitrate and phosphate values that indicated higher organic pollution in


4

V1 KD2 KP1 K5 KD4 V3 K4 I3 N3 I1 V2 K3 N4 I2 K1 I0 N1 N2 KD1

0

2

Dendrogram based on hierarchical cluster analysis, showing similar and different sites clustered as per prevalent threats at each site (site codes elaborated in Table 1)

6

8

Figure 5. Cluster analysis chart showing similar sites based on prevalent threats

10

Do Protected Areas of India’s Western Ghats conserve fish diversity?

High threats

Non-PAs (Table 5). We also recorded exceptionally high coliform counts (≥1600 mpn/100ml) in some of the RF and WLS sites. Reserve Forest sites recorded higher intensity of threats and were more similar to unprotected sites than to PAs (Figure 5). The Kallada River recorded the highest number of freshwater fish species (36) for any river in the landscape, followed by Neyyar (31), Ithikkara (18), Karamana (14) and Vamanapuram (14). Neyyar and Karamana, the rivers closest to the capital city, Thiruvananthapuram, had the most significant and negative-impact land-use changes over the last 20 years. The Vamanapuram and Kallada rivers were the least affected in terms of land-use change (Appendix 3). People interviewed were mostly aware of the negative impacts of various ‘threats’ to river systems and fish resources. Sand-mining, dynamite fishing, organic waste disposal and untreated acid waste disposal from rubber plantations were found to be the most critical threats (Table 4). However, many correspondents showed complete indifference, when asked about important measures for river conservation and reduction of threats. The existing legislation pertaining to wildlife conservation, environmental protection, water conservation, biodiversity, or Protected Area management did not even mention freshwater fish diversity, conservation or exploitation guidelines. However, a recently passed Inland Fisheries Act (Kerala), is seriously flawed and inadequate in addressing any of the pending issues with regard to species/habitat conservation. The framework for

Medium threats

Low threats

conservation of indigenous and endemic freshwater fishes in India is thus found to be virtually nonexistent.

Discussion: Conservation implications Protected Areas (PAs) in the Southern Western Ghats are found to be very important for conservation of endemic fish species. This reflects freshwater fish endemism in higher, more inaccessible reaches of the hill ranges, where physical isolation of stream habitats has led to higher endemism rates (Sheldon 1988). Thus, PAs in this landscape would play an important role in conservation of endemic fish fauna. Bias in PA selection towards higher altitudes (Joppa & Pfaff 2009), although criticized, seems important for rare, endangered and biologically unique freshwater fish species [for example: torrent fishes of the family Balitoridae, hill-stream catfishes like Glyptothorax spp. and barbs like Garra spp., even commercially important fishes such as Mahseer Tor spp. facing severe population declines (Dahanukar et al. 2003), in unprotected areas]. The PA coverage for endemic and endangered taxa was thus high in our study (unlike Bergl et al. 2007). It must be noted that these species were never recorded in mid-elevation areas in unprotected areas, possibly because of dynamite-fishing and other disturbances. Careful translocation and release of such rare endemics (Wikramanayake 1990) could play an important role 13


Do Protected Areas of India’s Western Ghats conserve fish diversity?

in their conservation even in non-PA areas, provided existing threats are mitigated. We also found that common species that are widely distributed across the landscape and using a wide range of habitats, also had higher relative abundance inside mid-elevation sites at PAs (Devictor et al. 2007). However, riverscape-level protection of freshwater fishes is inadequate in the present situation. The populations of many species in mid-elevation river zones have been heavily depleted by a wide range of threats. Most midland river zones showed large changes in land-use, with remarkable increases in area under Hevea brasiliensis (Rubber) and Acacia auriculiformis plantations. These land-use changes have been most prominent in midland unprotected areas (Kumar 2006). Expected species richness of freshwater fishes was highest for mid-elevation sites (inside and outside PAs), based on previous information (Easa & Shaji 2003, Thomas 2004). We also found a humped specieselevation relationship that may suggest a middomain effect (Fu et al. 2006) on species richness. Mid-elevation protected areas had much higher richness than rubber plantations at similar altitudes. In unprotected areas, the lower elevation sites had lowest endemism, but higher total species richness than PAs due to higher stream order, contribution from tributaries, and higher occurrence of marine and brackish-water species. Studies in this region over the last 50 years, from Silas (1951) to Thomas (2004) have either been restricted to a few groups or biased towards lower elevations. It appears that certain species were assumed present in high elevations without actual sampling, or owing to taxonomic misidentification. The spatial coverage of our study has been wider and the focus more ecological. The best possible use of even sporadic prior information on fish fauna has been made in developing checklists, and we hope they would serve as a guide to policy makers and managers, as well as conservation scientists. The Ariyankavu/Shenkotta pass, the northern geographic boundary of this region, is thought to be an important biogeographic barrier for distribution of many vertebrate taxa. We suggest that distribution of many species does not respect this barrier. The few exceptions present could be because of the affinities with Sri Lankan species, 14

not by isolation from northern rivers. We also found high morphological variation in Puntius fasciatus, a species (or species complex; Jayaram 1991) found in all five rivers. This leads us to report the presence of a potential novelty (Abraham et al. In Prep.). Range extensions to rivers originating in the Ashambu Hills were recorded for Garra mcclellandi, Garra hughi, Puntius mahecola and Puntius jerdoni. As expected, all sites within PAs (especially the WLSs) were similar to each other in magnitude of threats. However, ‘partially protected’ RF sites clustered together with non-PA sites, indicating similar threat intensity and human interference. High coliform counts within some PAs may be an indication of high human movement and usage of hill streams. This could be due to a higher influx of tourists and pilgrims accessing certain PAs. Based on these comparisons, we also identified sites inside WLSs and RFs that require higher management intervention and conservation measures. This approach can be extended to more sites to identify sites critical to conservation of freshwater fishes (Darwall & Wie 2005). Presence of threats within PAs suggests that river conservation even within terrestrial PAs (Nel et al. 2007) needs to be improved. The Shendurney WLS (Kallada River) was found to be relatively the ‘best’ managed protected area in terms of conservation and monitoring, and Neyyar WLS had the most intrinsic threats. Some fish species were recognized as indicator species owing to peculiarities in their occurrence across the landscape (Lawler et al. 2003). For instance, the endangered Malabar Mahseer Tor malabaricus, widely distributed across the landscape, was found mainly in streams within PAs. This species has been heavily affected by dynamiting and overfishing through much of its range, and might have a few refuges left, within PAs. Presence of sensitive species such as Channa spp. (resident predators) indicates relatively pristine habitat condition and absence of dynamiting, while presence of loaches or gobies (benthic dwelling species) indicates absence of sand-mining. Exotic species such as the Common Carp Cyprinus carpio and the Grass Carp Ctenopharyngodon idella, introduced in dam reservoirs as commercial food fishes, may have a severe impact on local food fishes (Koehn 2004), particularly Mahseer and local carps,


Do Protected Areas of India’s Western Ghats conserve fish diversity?

and abundances in localities where Common Carp are present can help us estimate relative impact of exotic fishes. Other exotics like Rohu Labeo rohita, Catla Catla catla and Mrigal Cirrhinus mrigala from northern rivers are also problematic for the survival of indigenous species. Invasive species such as the Nile Tilapia Oreochromis mossambicus were reported to be very common almost throughout the landscape. In sporadic cases, exotic aquarium species like South American Suckermouth Catfish of the family Loricaridae (species often unknown to respondents) were collected from natural water bodies. An additional threat is the illegal collection of endemic species from protected areas for the international aquarium trade. We were informed of several species of loaches of the families Balitoridae and Cobitidae, being in demand abroad. This extraction of endemic loach species occurs inside PAs because, as our study shows, most endemic hill-stream fishes are present only inside PAs. So, such illegal collection of such species is rampant in certain areas with easier access and through intimation with local ground staff. At the landscape scale, our study reflects the widespread apathy towards freshwater conservation, and linked to it a ‘boom-and-bust’ culture (Raghavan et al. 2007) towards freshwater fish diversity or fish resources. This attitude is clearly reflected in the legislation instruments that are available for freshwater biodiversity conservation in India. None of the environment- or water-related acts, or acts related to ‘fish resources’ explicitly treat indigenous freshwater fish conservation as of any concern. There is no mention of the word ‘fish’ in many of the acts that have proved highly effective in conservation of other wildlife. Non-existent legislation is ultimately responsible for the threats to freshwater fish species inside PAs, as the enforcing authorities seem to have no awareness regarding fish biodiversity and no legal facility to take appropriate action against offenders. Even ground staff such as forest watchers and contract labourers such as trek-path workers use forest streams to catch fishes (prohibited in a wildlife sanctuary as per the Wild Life (Protection) Act, (1972)) using destructive techniques such as bio-poisons, dynamite and gill-nets. Forest guards would quiz us about the best sites to catch large

fishes. We noticed high levels of indifference in the ground staff of individual PAs. A catchment-scale approach to fish conservation demands inclusion of local stakeholders in policy and decision-making, with a clear ecological understanding of issues pertaining to freshwater conservation at multiple levels (Collares-Pereira & Cowx 2004). However, even these local stakeholders, with all their awareness about environmental problems, were found to be highly ambivalent towards conservation initiatives. Therefore, we strongly advocate directed management intervention by regulatory authorities (fisheries, irrigation, forests, wildlife, tourism etc.) at present, driven by scientifically established understanding. We propose that targeting PA managers for training programs about maintaining ecological functions to safeguard the important role of PAs for freshwater fish conservation can be a good first step. At other levels of management, such as for rubber plantation owners, agriculturists and rural and urban citizens, co-management systems for river stretches could be envisioned, with multiple modes of resource ownership and utilization (Linke et al. 2007, Sarkar et al. 2008). These may range from private control (privately managed estates can be involved actively in restoration and conservation of river stretches) in the midlands along with village self-government led initiatives. New provisions of the Wildlife (Protection) Act can be used to create community reserves and conservation reserves, with varying roles of local communities in management and conservation. In the lowlands, community reserves could potentially be very useful for management of fish resources. The study region is also home to the Kani and Vedar tribes, living in landholdings within and around PAs (wildlife sanctuaries). Some of them indulge occasionally in dynamite-fishing and use of poisons derived from plants, to induce fish kills. The Kanis have started cultivating rubber and other monoculture crops in their land holdings inside some PAs and such activities are affecting the water bodies inside the PA, especially noticed in Neyyar WLS. There has been a drastic assimilation of urban culture and lifestyle adopted by these scheduled tribals on reservation lands inside PAs (Miller & Murugan Kani 2004), and is leading to severe ecological impacts and pollution 15


Do Protected Areas of India’s Western Ghats conserve fish diversity?

Despite this problem, it is true that lower accessibility of people to PAs controls intensity of threats to freshwater sources and ecologically sensitive hill-streams. Outside PAs, the most significant threats recognized by people were sand-mining, dynamite fishing, and dumping of untreated wastes and acidic wastes from rubber plantations. They further said that using the rivers even for bathing had become a dangerous thing, either due to allergic reactions caused by rubber estate pollution, or by slippage of the unstable river bed due to prolonged sand-mining. People recognized all these activities as illegal and said that they take place in connection with local politicians and influential individuals. Many people reported that food fishes had become rare in their area because of constant dynamite fishing. During our sampling and interview phase, we were occasionally threatened by certain hostile groups of people operating with the sand-mafia, prostitution rackets, illicit liquor brewers and unemployed youth involved in illegal activities. Threats to social security such as criminal gangs, illicit liquor production and organized prostitution rackets along the stream banks (though seemingly unrelated) make many sites difficult to access and affect conservation and research efforts. There were also some ‘anomalous’ sites both inside and outside PAs, where expected threat levels were not seen. Some sites, although inside Reserve Forests, are used by people for extraction of sand and illegal fishing, like the lower reaches of the Kulathupuzha Reserve forests. On the other hand, the presence of religious areas in the same area (a temple) led to a reduction in direct or intentional threats around the temple premises. For instance, river reaches near temples had much lower levels of dynamite fishing or sand mining. It is possible that community control through religious collective action might lead to a positive attitude towards conservation. Our expectation that lack of awareness about ecological threats led to the high prevalence of destructive practices such as sand-mining or dynamiting did not hold true. On the contrary, we discovered that people knew perfectly well the ultimate cause of their actions, but were completely indifferent towards it. Answers provided by 16

interview respondents often described in detail their ecological understanding of these threats. Despite complaints about dynamite fishing, their attitude continued to be indifferent. Many were actually proud of being a ‘dynamite fisher’ as they said they got ‘lots of fishes’. However, there were also people who were against such practices but felt helpless to act against organized groups and poorer people who often practiced illegal activities, which fetched easy money. Kerala is India’s most literate state and has had a long tradition of rural education that has definitely played a role in local conservation practices. It is therefore very difficult to understand this paradox. In conclusion, we emphasize that presence of Protected Areas, despite little active enforcement and indifferent management of freshwater resources is important for conservation of many endemic and threatened fish species. However, PAs are not enough for conserving lowland fish species and thus have only partial benefits for freshwater fish diversity. State managed protected zones along the river and community-based conservation initiatives including local self-governments, religious bodies and NGOs are needed for effective conservation of freshwater fish communities in the lowlands. Most importantly, a wide change in local attitudes and legislation capacity to protect freshwater ecosystems and aquatic biodiversity are needed urgently.

Conservation Recommendations This study found that Protected Areas in the Ashambu Hills are of high importance for conservation of many Western Ghats endemic species of freshwater fishes. This also holds true for species considered as ‘range-restricted’, ‘rare’ and ‘threatened’ by different conservation assessments done in the landscape or in the surrounding areas (Biju et al. 2000, Easa and Shaji 2003, Sreekantha et al. 2007). Migratory species of commercial and conservation importance (e.g. the endangered Malabar Mahseer Tor malabaricus) also depend on hill streams for a good part of their life-cycle (Sheldon 1988, Dahanukar et al. 2003). Thus, the


Do Protected Areas of India’s Western Ghats conserve fish diversity?

onus for active conservation of these species rests with PA managers, in this case the Kerala State Department of Environment and Forests, and the local Forest Divisions in charge of the five protected areas in this landscape. We find that forest officials and even ground staff are not fully aware of the importance of conserving rare and endemic freshwater fishes that find refuge inside PAs. As we have discussed already, considering fish as ‘wildlife’ or ‘biodiversity’ is still a non-existent concept owing to lack of legislation that addresses freshwater fish conservation. Even within PAs, although at a lesser magnitude, a multitude of threats to freshwater fishes prevails, that can be minimized only by active involvement and sensitization of regulatory authorities. We provide recommendations about PA managers regarding their potential role in conservation and monitoring of threats to hill stream habitats and fish species within PAs. a) Most of the protected areas in the Ashambu Hills landscape comprise the higher reaches and more inaccessible areas, and extend upto the catchment areas of dams built across the rivers of the area. Reservoir utilization and management are under the purview of district-level irrigation and fisheries departments, but the surrounding reaches of forest and stream networks fall under the Forest Department’s PA jurisdiction. Reservoirs act as significant artificial disturbances to the fish ecology of both feeder-streams/tributaries and the river itself, through a variety of interventions by departments other than the Forest Department. The release, cultivation and production of exotic invasive fish species within reservoirs, predominantly for commerce is the biggest direct threat to freshwater fish species in PAs. Endemic and range-restricted species are highly affected following the introduction of invasive species in the reservoirs. This is thus a case which requires inter-departmental co-ordination. The irrigation, power and fisheries departments and their senior officials need to be involved in the process of PA management, as the reservoir is of importance in management of human activity, and ecological conservation in the area. Strict bans are needed to stop further introduction of exotic food fishes such as Oreochromis mossambicus, Cyprinus carpio, Catla catla, Labeo rohita, Cirrhinus mrigala and Ctenopharyngodon idellus. Alongside

this, the Fisheries Department will need to develop alternatives by breeding large, fast growing local species, which might prove to be a lesser threat to indigenous endemics. b) Presence of many local threats was recorded inside PAs across the landscape. These chiefly involved sporadic dynamite fishing, use of biopoisons for fishing, exotic invasive fishes, pollution and solid wastes from unregulated tourism and pilgrim movement, occasional sand-mining in some Reserve Forest (RF) areas and rubber plantations on lands within PAs allotted to the Kani tribes. We strongly recommend regular monitoring of human activity within the area. This is particularly true for two user groups: tourists from Thiruvananthapuram or neighboring areas, and forest watchers, trek-path workers and forest department labourers. Tourists, pilgrims and trekkers indulge in a lot of point-source pollution and solid-waste dumping. Plastic wastes, alcohol bottles, and several such non-biodegradable materials are thrown into streams, which can have serious implications for fish species. Alcohol bottles especially, are discarded in a very irresponsible fashion i.e. by smashing them onto rocks. This creates problems for resident animals that frequent water bodies to drink water. PA management could incorporate strategies for regulating the higher recent influx of tourists and pilgrims to PAs through which the trek-paths to the revered mountain Agasthyamala, located inside Neyyar WLS, run. It would also prove good to check such visitors for possession of alcohol bottles and other pollutant articles, prior to granting them permission of entry into any PA. There has also been an increase in such irresponsible venturing into protected forests, under the label of ‘ecotourism’. Contract labourers employed by the department often camp by stream sides and use destructive methods to catch fish for the pot, most importantly, using dynamite and bio-poisons (plant derived) to fish out hill streams. These practices are also used by some members of the Kani tribes inhabiting some PA areas. We found that dynamiting had severely affected the endemic Malabar Mahseer, one of the region’s endemic and highly valuable food fish species. There needs to be increased patrolling and monitoring of not just terrestrial but also the access routes via dam 17


Do Protected Areas of India’s Western Ghats conserve fish diversity?

Gravel mined from the river bed of the Neyyar River

Sand illegally collected near the Poonthura Estuary in the Karamana River Drainage

Karamana River at the lower reaches, polluted by adjacent tourist resorts Sand mining in the Kallada River

18


Do Protected Areas of India’s Western Ghats conserve fish diversity?

improving the awareness towards freshwater fishes, of both forest staff and visitors/tourists. Overall, the Forest Departments need to read beyond the rule books. There needs to be a change in the perception of the managers towards freshwater fishes, from being mere ‘protein sources’ or ‘game’, to being highly important biodiversity conservation targets and critical ecosystem components that maintain freshwater ecosystem functions through trophic mass-balance and nutrient cycling.

Conclusion

reservoirs. Finally, penalizing offenders is necessary to control these disturbances within PAs. Amongst other threats, sand mining was also seen to be practiced within some RFs. This is the biggest threat to freshwater systems in the non-PAs, but the magnitude within PAs is much lower. There is an urgent need to curb sand mining activities wherever possible. People living around the dam areas fish in the reservoir waters, but often move into PAs for catching stream fishes. This activity needs to be banned to minimize impacts of fishing in hill streams in PAs. c) There is a need to improve existing information and interpretation centres for awareness about biodiversity. These centres, run by the forest departments are very informative for most higher taxa like mammals, birds and reptiles, but haven’t realized their true potential for aquatic organisms. They could be effectively combined with responsible ecotourism activities managed by the forest department, and help a great deal in

In this study, taking the Ashambu Hills as an example, we aimed at assessing if protected areas of the Western Ghats preserve fish species diversity. Our specific objectives were to: i) To estimate the representation of indigenous stream fish fauna in protected areas and outside: We found that Protected Areas were harbouring higher species richness and densities of endemic species as well as several widely distributed species. ii) To identify factors that significantly influence stream fish communities inside and outside protected areas: Anthropogenic pressures in the form of habitat destruction by sand-mining and dynamite fishing, over-fishing and pollution, negatively influenced fish communities in non-PAs, whereas dams and exotic species influenced fish communities inside PAs. iii) To identify measures that are required for optimal conservation of stream fishes in the study area: We have identified several measures for the optimal conservation of fishes. To begin with, a fundamental awareness of the richness and composition of fish species in the Western Ghats is lacking among the general public and even among many conservation professionals and the importance of river habitats for several organisms and local communities. The absence of legal provisions to protect threatened fish species is also a key issue that need to be addressed immediately. Finally, the regular, unscientific introduction of exotic species into protected areas that serve as refuge habitats for many endemic species also needs to be controlled. 19


Do Protected Areas of India’s Western Ghats conserve fish diversity?

The key finding of the study is that Protected Areas in the Ashambu Hills are of extremely high importance for conservation of many species of freshwater fishes endemic to the Western Ghats and even for many widely distributed species, depending on the extent of midland river stretches inside protected areas. However, most areas in the unprotected lowland and midland stretches are severely degraded and still under threat. Many anti-social elements operating along river stretches in illegal sand-mining and illicit-liquor brewing operations also hampered our research activities and attempts to access sampling points. Also, the weather has been extremely unpredictable with excessive rain received in the study area in the past year, when field-work was being carried out. Additionally, many stream areas, especially in the higher elevations that were frequented by irresponsible tourists, had been littered with glass shards from broken liquor bottles, with such areas being very challenging and proving injurious on some occasions. Yet, we were able to gather a vivid picture of the river systems and the fish fauna they support, in the Ashambu Hills Landscape and the mounting problems they face. The threats from this study can be generalized, albeit with varying degrees across most westflowing river systems in the highly human-

20

dominated Western Ghats landscape, especially in the southern parts. It is extremely important that people value river systems as a critical lifeline for the numerous ecosystem services provided in terms of providing clean water for drinking and all important domestic chores, as well as for flood control, agriculture and transfer of nutrients and sediment from the mountains into the plains. Rivers also are a major source of protein in the form of fishes, molluscs and crustaceans. Additionally, people are exploiting river sand sediment for buildings and other constructions. So, streams and rivers that service the entire landscape through which they flow need to be effectively managed and attempts made to restore them, before the situation becomes irreversible. But, in order to do this, there have to be topdown initiation on the governing body’s part, with effective monitoring and swift action taken towards curbing illegal activities. There still remain infinite dimensions remaining to be understood about rivers, but opportunities to understand the natural rhythms of rivers are becoming increasingly bleak, due to the multitude of anthropogenic modifications accorded to rivers. So, it is important to focus on aspects that require urgent attention and can be pragmatically addressed at the earliest to halt further negative changes.


Do Protected Areas of India’s Western Ghats conserve fish diversity?

The headwaters of the Vamanapuram River inside the Kallar Reserve Forest (1350 m ASL)

Undisturbed riverbed of the Karamana River inside Peppara Wildlife Sanctuary

The headwaters of the Kallada River inside the Shendurney Wildlife Sanctuary (1220m ASL)

Agasthyamala (1868m ASL), the highest peak in the Ashambu Hills

21


Some of the freshwater fish species found living in the streams originating from the Ashambu Hills:

1. Anguilla bengalensis 2. Mystus malabaricus 3. Puntus ticto 4. Devario malabaricus 5. Tor malabaricus 6. Carinotetraodon travancoricus 7. Pristolepis marginata 8. Channa diplogramma (juv.) 9. Puntius exclamatio 10. Xenentodon cancila 11. Nemacheilus triangularis 12. Puntius cf. fasciatus 13. Barilius bakeri 14. Garra mcclellandi


15. Horabagrus brachysoma 16. Etroplus suratensis 17. Bhavania australis 18. Puntius mahecola 19. Heteropneustes fossilis 20. Puntius jerdoni 21. Ompok malabaricus 22. Puntius filamentosus 23. Pseudambassis ranga 24. Garra hughi (Images 9., 10. & 18. by A. Bijukumar)


Do Protected Areas of India’s Western Ghats conserve fish diversity?

Students sampling fish and measuring stream parameters

Workshop introducing students to freshwater fish taxonomy, ecology and conservation organized at the Department of Aquaculture, University of Kerala © A. Bijukumar

24

Discussing the effects of existing (destructive) fishing techniques and recommending sustainable practices to local fishermen © Nikhil James

Robin Abraham participating in the ‘Western Ghats Freshwater Biodiversity Assessment Red-list Workshop’ organized by the IUCN © Kevin Smith


Do Protected Areas of India’s Western Ghats conserve fish diversity?

Table 1. Sampling sites for freshwater fish species in the Ashambu Hills landscape No. Sampling Site ID Name Protection1 Status 1. Neyyar 0 (N0) Athirumala PA 2. Neyyar 1 (N1) Meenmutty PA 3. Neyyar 2 (N2) Komba PA 4. Neyyar 3 (N3) Veeranakavu Non-PA 5. Neyyar 4 (N4) Mambazhakkara Non-PA 6. Karamana 1 (K1) Pandipathu PA 7. Karamana 2 (K2) - Non-PA 8. Karamana 3 (K3) Manjamoodu Non-PA 9. Karamana 4 (K4) - Non-PA 10. Vamanapuram 1 Kallar PA (V1) 11. Vamanapuram 2 Noor-acre Estate Non-PA (V2) 12. Vamanapuram 3 Vamanapuram Non-PA (V3) 13. Ithikkara 0 (I0) Chitthara, Palode PA RF 14. Ithikkara 1 (I1) Anchal Non-PA 15. Ithikkara 2 (I2) Ayur Non-PA 16. Ithikkara 3 (I3) Chathannoor Non-PA 17. Kulathupuzha 1 Kulathupuzha PA (KP1) 18. Kallada 1 (KD1) Umayar PA 19. Kallada 2 (KD2) Urukunnu Non-PA 20. Kallada 3 (KD3) West Kallada Non-PA

Elevation range2, Land-use H, Rainforest, Shola, Grassland M, Semi-evergreen forest M, Moist-deciduous forest, Kani settlement L, Rubber plantation, Coconut plantation, Settlement L, Coconut plantation, Banana, Tapioca, Paddy, Settlement H, Evergreen forest, Shola, Grassland M, Rubber plantation, Settlement M, Rubber plantation, Coconut plantation L, Urban, coconut plantation, Settlement H, Evergreen forest, Shola, Grassland M, Rubber Plantation L, Urban, Coconut Plantation H, Oil-Palm Plantation, Reserve Forest M, Rubber plantation, Temple L, Coconut plantation, Paddy L, Near estuary M, Reserve Forest, Settlement M, Evergreen forest M, Rubber plantation, Settlement L, Coconut plantation, Settlement, Semi-urban

Key: 1 – PA (Protected Area), Non-PA (Non-Protected Area). 2 – L = Lowland, M = Midland, H = Highland; Shola is the local name for Montane Cloudforest.

25


Do Protected Areas of India’s Western Ghats conserve fish diversity?

Table 2. Details of ecological and anthropogenic covariates measured at sampling sites. Variable Units, measurement details Elevation (ct) Metres above sea level, GISa Slope (ct) Degrees, GIS Aspect (ct) Ratio, GIS Stream order (o) Order, GIS, Toposheetsb Substrate (cg) Substrate category, Observation Canopy cover (ct) Percentage, Observation Surface Temperature (ct) Degrees Celsius, Water thermometer Air Temperature (ct) Degrees Celsius, Thermometer Habitat Type (cg) Category, Observation, GIS plantation, Semi-urban / urban area Protection Status (cg) Category, Observation, GIS Distance from Metres, GIS settlement/town PA; reservoir (ct) Plantation type (cg) Category, Observation, GIS, Toposheets Water quality Laboratory analysesd variablesc (ct) Observation, Interviews Threats (p/a)e

Description Obtained from satellite imagery Obtained from satellite imagery Obtained from satellite imagery Stream order Muddy, rocky, sandy, and combinations of these types Measured as percent cover above stream width Measured from water surface for day and night Measured for day and night Forest, Rubber plantation, Coconut

Wildlife Sanctuary, Reserve Forest, Non-protected Distances as-the-crow-flies; for reservoir – both upstream and downstream distances Rubber, Coconut, Oil palm, Tapioca, Banana, Paddy; Observation Physico-chemical and biological parameters (Table 5) Sand-mining, dynamite fishing, industry, solid wastes, settlement, pilgrimage, overfishing, crop, wood plantation, non-wood plantation

Key: a – GIS software Idrisi ANDES 15.0 (ClarkLabs 2006); and Google Earth™; b – Survey of India Toposheets of resolution 1: 25,000 and 1: 50,000 cm, published in 1989-1990. c – Physico-chemical parameters assessed at each site. d– Laboratory analyses conducted by the Regional Research Laboratory (RRL)[CSIR], Industrial Estate P.O., Thiruvananthapuram 695019, Kerala, India. e – Threats identified from the IUCN Red List Guidelines (IUCN 2010) and from our interviews’ data. Acronyms in brackets in the column ‘Variable’ refer to type of variable: ct – continuous, cg – categorical, o – ordinal, p/a – presence/absence

26


Do Protected Areas of India’s Western Ghats conserve fish diversity?

Table 3. Species richness across Protected Areas, rubber plantations and lowland agriculture/ settlement areas in the Ashambu Hills landscape

Land-use Protected Area Rubber Plantation Lowland agriculture and semi-urban areas

Total species richness Sampled species and Western Ghats richness2 1 endemic species richness 63 (21) 33

Estimated species richness3 57 (10)

73 (20)

25

50 (14)

78 (7)

29

62 (13)

Key: 1 – From review of previous literature with information from the area, (Easa and Shaji 2003, Biju et al. 2000, Thomas 2004). Numbers in brackets are standard deviations, derived from gaps in information, by assigning subjective probability classes to species with uncertain status. Std. deviations indicate sampling bias in previous studies, towards lowland areas that are easily accessible. 2 – Actual species richness observed in our samples from the three areas. A total number of 60 species was sampled. 3 – Estimated species richness from Bayesian hierarchical model for occurrence and detection probabilities. Numbers in brackets are standard deviations around estimated richness.

27


Do Protected Areas of India’s Western Ghats conserve fish diversity? Table 4. Threats to freshwater habitats and fish species recorded in the landscape. Threat

Rank Area affected (PA/NonPA) (Low/Mid/High) (Habitat)

Fishes found to be critically affected

Target groups/Solutions proposed/Agencies to be involved for change

Non-PAs, midlands and Lowlands throughout, occasional in PAs

Species belonging to the families Gobiidae, Cobitidae and Balitoridae; also Puntius spp. and Hypselobarbus spp. of Cyprinidae

Sand-mining mafia / Complete ban, curbing the mafia / Environmental action groups, local self-governments & police

Non-PAs, throughout, occasional in PAs: especially Neyyar & Karamana

Tor malabaricus, Hypselobarbus curmuca, Wallago attu, Ompok bimaculatus, Horabagrus brachysoma, resident predators such as Channa spp.; also smaller endemic fishes

Unemployed youths, forestdwelling tribes, nuisance elements in villages / Complete ban / Village Panchayats, community-level monitoring agencies

Sand-mining

1

Dynamite-Fishing

2

Rubber acid wastes

3

Throughout Non-PAs in midlands

Channa spp., and other resident fishes.

Rubber plantation owners, labourers / Complete ban, better eco-friendly disposal of wastes / Environmental research, Waste Management, Private Initiative

Solid wastes

4

Throughout, also in PAs because of human movement, tourism and pilgrimage

Most native riverine fish species

Tourists, pilgrims, forest watchers, trackers, guards, urban and rural citizens, plantation owners and farmers / Reduction necessary, monitoring / Forest and Environment Departments, Irrigation and Village or Town Development Authorities, Town Planning

Urban sewage and industrial wastes

5

Lowlands, extremely high in Karamana, Neyyar & Kallada

Most native riverine fish species

Everyone living in the landscape / Severe reduction necessary / Forest and Environment Departments, Irrigation and Village Town Development Authorities, Town Planning

Overfishing

6

Throughout the landscape except PAs.

Mahseer Tor spp., Hypselobarbus spp., Channa spp., Anguilla spp., and all major food-fishes.

Fishermen and citizens / Regulated fishing, monitoring / Fisheries Departments, Village Self-Governments, Community Action Groups

Exotic species

7

Reservoirs and surrounding streams, in PAs and non-PAs

Major native foodfishes (Tor spp.) and many species affected by exotics Cyprinus carpio & Oreochromis mossambicus

Fisheries and Agriculture Departments / Ban on further introductions of exotic species /Environmental NGOs and Action Groups

28


Do Protected Areas of India’s Western Ghats conserve fish diversity?

Table 5. Results of water quality assessments of water samples from 14 sampling sites (4 PA*, 10 Non-PA) a) Physico-chemical parameters No. Sample pH Area

Conductivity, COD Sulphate MS (mg/l) (mg/l)

PO4` (mg/l)

NO3 (mg/l)

SiO2 Cl (mg/l) (mg/l)

HCO3 (mg/l)

1. NEY-03

7.03

39.2

14

10. 6

0.007

0.108

0.845

5.73

48

2. NEY-04

7

39.7

14

6.5

BDL

0.085

0.78

5.78

46

3. KAR-03

7.12

28.3

14

3. 3

0.284

0.225

0.717

4.75

36

4. KAR-04

7.06

39. 9

19

6. 1

BDL

0.094

0.727

4.68

50

5.

ITK-1*

6.69

110.6

25

14. 7

0.008

0.104

0.909

16

102

6.

ITK-2

6.57

107.1

30

10. 9

0.01

0.151

1.25

13.6

116

7.

ITK-3

6.76

96

28

4. 8

0.026

0.068

1.09

15.3

86

8.

KLD-2

6.9

33..5

10

2. 7

0.006

0.091

0.546

5.04

36

9.

KLD-3

6.85

30..3

14

1. 4

0.027

0.178

0.518

4.97

40

10. VAM-3

6.94

68..3

25

4. 7

0.02

0.119

1.19

7.96

86

11. VAM-1*

6.53

33. 8

12

3.77

BDL

0.2

0.76

2.57

50

12. VAM-2

6.56

39

11

2.54

BDL

0.08

0.64

2.59

54

13. KAR-1*

6.38

29. 3

14

0.91

BDL

0.11

0.44

2.92

32

14. NEY-1*

6.16

47. 7

16

1.26

BDL

0.002

0.56

3.32

56

b) Biological parameters Sample Area Total bacterial count/ml × 103

Presence/absence of Coliform

Coliform count mpn/100ml

e-coli count/ml

NEY-03

2.5

present

≥1600

6

NEY-04

2.8

present

≥1600

4

KAR-03

3

present

≥1600

8

KAR-04

3.2

present

≥1600

5

2

present

1600

3

ITK-2

2.2

present

900

4

ITK-3

1.8

present

1600

3

KLD-2

2.3

present

≥1600

2

KLD-3

2.5

present

1600

2

VAM-3

3

present

900

3

VAM-1*

1.5

present

500

10

VAM-2

1.2

present

300

5

KAR-1*

3.2

present

≥1600

240

NEY-1*

3.5

present

≥1600

530

ITK-1*

29


Do Protected Areas of India’s Western Ghats conserve fish diversity?

1. 2. 3.

4. 5. 6. 7. 8.

9. 10. 11. 12. 13.

14.

15. 16. 17. 18.

19. 20.

30

ABELL, R., ALLAN, J.D. & LEHNER, B. (2007) Unlocking the potential of protected areas for freshwaters. Biological Conservation, 134, 48–63. ABRAHAM, R.K., KELKAR, N.S., BIJUKUMAR, A., & SHAJI, C. P. (2010) Puntius sp. novo., a new cyprinid species. Manuscript In Prep. ADAMSON, E.A.S., HURWOOD D. A. & MATHER. P. B. (2010) A reappraisal of the evolution of Asian snakehead fishes (Pisces, Channidae) using molecular data from multiple genes and fossil calibration. Mol. Phylogenet. Evol. 56(2): 707-717. ALLAN, J.D. & FLECKER, A.S. (1993) Biodiversity conservation in running waters. BioScience, 43, 32– 43. ALMEIDA, P.R., QUINTELLA, B.R., COLLARES-PEREIRA, M.J., COELHO, M.M. & COWX, I.G. (2002) Freshwater fish conservation: options for the future. ANAND, M.O., KRISHNASWAMY, J., KUMAR, A. & BALI, A. 2010. Sustaining biodiversity conservation in human-modified landscapes: remnant forests matter. Biological Conservation, In Press. ARUNACHALAM, M. (2000) Assemblage structure of stream fishes in the Western Ghats (India). Hydrobiologia, 430, 1–31. BAWA, K.S., DAS, A., KRISHNASWAMY, J., KARANTH, K.U., KUMAR, N.S., & RAO, M. (2007). Critical Ecosystem Partnership Fund – Ecosystem Profile. Western Ghats and Sri Lanka Biodiversity Hotspot. Western Ghats region. ATREE, Bangalore, India. BERGL, R.A., OATES, J.F. & FOTSO, R. (2007) Distribution and protected area coverage of endemic taxa in West Africa’s Biafran forests and highlands. Biological Conservation, 134, 195–208. BHAT, A. (2003) Diversity and composition of freshwater fishes in river systems of central western ghats, India. Environmental Biology of Fishes, 68, 25–38. BHAT, A. (2004) Patterns in the distribution of freshwater fishes in rivers of Central Western Ghats, India and their associations with environmental gradients. Hydrobiologia, 529, 83–97. BHAT, A. & MAGURRAN, A.E. (2006) Taxonomic distinctness in a linear system: a test using a tropical freshwater fish assemblage. Ecography, 29, 104–110. BIJU, C.R., THOMAS, K. R. & AJITHKUMAR, C.R. (2000). Ecology of hill streams of Western Ghats with special reference to fish communities. Final Report, 203 pp, Bombay Natural History Society, Mumbai, India. BOSSUYT, F., MEEGASKUMBURA, M., BEENAERTS, N., GOWER, D.J., PETHIYAGODA, R., ROELANTS, K. ET AL. (2004) Local endemism within the Western Ghats-Sri Lanka biodiversity hotspot. Science, 306, 479. CAMBRAY, J.A. (2003) Impact on indigenous species biodiversity caused by the globalisation of alien recreational freshwater fisheries. Hydrobiologia, 500, 217–230. CHAKRABARTY, D. & DAS, S.K. (2006). Fish community structure and ecological degradation in tropical rivers of India. Web Ecology, 6, 27–36. COLLARES-PEREIRA, M.J. & COWX, I.G. (2004) The role of catchment scale environmental management in freshwater fish conservation. Fisheries management and Ecology, 11, 303–312. COLLEN, B., MCRAE, L., KOTHARI, G., MELLOR, R., DANIEL, O., GREENWOOD, A., AMIN, R., HOLBROOK, S. & BAILLIE, J. (2008) Living Planet Index. 2010 and beyond: rising to the biodiversity challenge (edited. by J. Loh), WWF, Gland, Switzerland. COLWELL, R.K. 2006. EstimateS: Statistical estimation of species richness and shared species from samples. Version 8. Persistent URL <purl.oclc.org/estimates>. Accessed 20/4/2010. CORBACHO, C. & SÁNCHEZ, J.M. (2001) Patterns of species richness and introduced species in native freshwater fish faunas of a Mediterranean-type basin: the Guadiana River (southwest Iberian Peninsula). Regulated Rivers: Research & Management, 17: 699–707.


Do Protected Areas of India’s Western Ghats conserve fish diversity?

21. 22.

23.

24. 25. 26. 27. 28.

29. 30. 31. 32. 33.

34. 35.

36. 37. 38.

39. 40. 41.

COWX, I.G. (2002) Analysis of threats to freshwater fish conservation: past and present challenges. Conservation of Freshwater Fishes: Options for the future, 201–220. CRIVELLI, A.J. (2002) The role of protected areas in freshwater fish conservation. Conservation of freshwater fishes: options for the future. Fishing News Books, Blackwell Science, Oxford, United Kingdom, 373–388. CURTIS, B., ROBERTS, K.S., GRIFFIN, M., BETHUNE, S., HAY, C.J. & KOLBERG, H. (1998) Species richness and conservationof Namibian freshwater macro-invertebrates, fish and amphibians. Biodiversity and Conservation, 7, 447–466. BASAK, P., JAMES, E.J. & NANDESHWAR, M.D. (1995) Water Atlas of Kerala. Central Water Resources Development and Management Institute / STEC, Calicut, Kerala, India. DAHANUKAR, N., RAUT, R. & BHAT, A. (2004) Distribution, endemism and threat status of freshwater fishes in the Western Ghats of India. Journal of Biogeography, 31, 123–136. DAMU, T. (2003). Helping “Ecosystem People” protect wilderness and their own welfare. USDA Forest Service Proceedings RMRS-P-27. DANIELS, R.J.R. (2002). Freshwater fishes of Peninsular India. In. Gadgil, M. (edited) India - A lifescape 2. Universities Press, Hyderabad, pp 287. DARWALL, W.R.T. & VIÉ, J.C. (2005) Identifying important sites for conservation of freshwater biodiversity: extending the species-based approach. Fisheries Management and Ecology, 12: 287– 293. DEVI, K.R., INDRA, T.J., RAGHUNATHAN, M.B. & RAVICHANDRAN, M.S. (2005) Fish fauna of the Anamalai hill ranges, Western Ghats, India. Zoos’ Print Journal, 1809–1811. DEVICTOR, V., L. GODET, L., JULLIARD, R., COUVET, D. & JIGUET, F. (2007). Can common species benefit from protected areas? Biological Conservation, 139, 29-36. DUDGEON, D. (2005) River rehabilitation for conservation of fish biodiversity in monsoonal Asia. Ecology and Society, 10, 15. DUNCAN, J.R. & LOCKWOOD, J.L. (2001) Extinction in a field of bullets: a search for causes in the decline of the world’s freshwater fishes. Biological Conservation, 102, 97–105. DUDGEON, D., ARTHINGTON, A.H., GESSNER, M.O., KAWABATA, Z.I., KNOWLER, D.J., LÉVÊQUE, C. ET AL. (2005) Freshwater biodiversity: importance, threats, status and conservation challenges. Biological Reviews, 81, 163–182. EASA, P.S. & SHAJI, C.P. (2003). Biodiversity Documentation for Kerala - Part 8: Freshwater Fishes - KFRI Handbook No.17, Kerala Forest Research Institute, Peechi, Kerala, India. ESCHMEYER, W.N., AND FONG, J.D. (2010). Species of Fishes by family/subfamily. On-line version dated 31/05/2010. URL: http://research.calacademy.org/research/ichthyology/catalog/ SpeciesByFamily. asp FAUSCH, K.D., TORGERSEN, C.E., BAXTER, C.V. & LI, H.W. (2002) Landscapes to riverscapes: bridging the gap between research and conservation of stream fishes. BioScience, 52, 483–498. FREEMAN, M.C., BOWEN, Z.H., BOVEE, K.D. & IRWIN, E.R. (2001). Flow and habitat effects on juvenile fish abundance in natural and altered flow regimes. Ecological Applications, 11, 179-190. FU, C., HUA, X., JUN, L., CHANG, Z., PU, Z., & CHEN, J. (2006). Elevational patterns of frog species richness and endemic richness in the Hengduan Mountains, China: geometric constraints, area and climate effects. Ecography, 29, 919-927. GOVERNMENT OF INDIA. 2010. Ministry of Environment and Forests. Website.URL: http://moef.nic.in/ modules/rules-and-regulations/ Accessed 25/5/2010. HABIT, E., BELK, M.C., TUCKFIELD, R.C. & PARRA, O. (2006) Response of the fish community to humaninduced changes in the Biobıo River in Chile. Freshwater Biology, 51, 1–11. HUMPL, M. & PIVNICKA, K. (2006) Fish assemblages as influenced by environmental factors in streams in protected areas of the Czech Republic. Ecology of Freshwater Fish, 15, 96–103. 31


Do Protected Areas of India’s Western Ghats conserve fish diversity?

42. IUCN 2010. IUCN Red List of Threatened Species. Version 2010.1. http://www.iucnredlist.org. Downloaded on 11 March 2010. 43. IUCN Standards and Petitions Subcommittee. 2010. Guidelines for Using the IUCN Red List Categories and Criteria. Version . Prepared by the Standards and Petitions Subcommittee. http://intranet.iucn. org/webfiles/doc/SSC/RedList/RedListGuidelines.pdf. 44. JAYARAM, K.C. (1994). The freshwater fishes of India, Pakistan, Bangladesh, Burma and Sri Lanka – a handbook. Zoological Survey of India, Kolkata, India. 45. JAYARAM, K.C. (1991). Revision of the Genus Puntius Hamilton. Records of the Zoological Survey of India – Occasional Paper No. 135, Zoological Survey of India, Kolkata, India. 46. NEL, J.L., REYERS, B., ROUX, D. J. & COWLING, R.M. (2009) Expanding protected areas beyond their terrestrial comfort zone: Identifying spatial options for river conservation. Biological Conservation, 142, 1605-1616. 47. JOHNSON, J.A. & ARUNACHALAM, M. (2009) Diversity, distribution and assemblage structure of fishes in streams of southern Western Ghats, India. Journal of Threatened Taxa, 1, 507–513. 48. JOPPA, L.N., & PFAFF, A. (2009). High and far: biases in the location of Protected Areas. PLoS One, 4, 1-6. 49. JOWETT, I.G., & RICHARDSON, J. (1996). Relative effects of in-stream habitat and land use on fish distribution and abundance in tributaries of the Grey River, New Zealand. New Zealand Journal of Marine and Freshwater Research, 30, 463-475. DOI 0028-8330/96/3004-0463. 50. KEITH, P. (2000) The part played by protected areas in the conservation of threatened French freshwater fish. Biological conservation, 92, 265–273. 51. KOEHN, J.D. (2004) Carp (Cyprinus carpio) as a powerful invader in Australian waterways. Freshwater Biology, 49, 882–894. 52. KRISHNASWAMY, J, LELE, S & JAYAKUMAR, R. (2005) (Editors) Hydrology and watershed services in the Western Ghats: Effects of Land-cover and Land-use change. Tata McGraw-Hill, New Delhi, India. 53. KUMAR, B.M. (2006). Land use in Kerala: changing scenarios and shifting paradigms. Journal of Tropical Agriculture, 42, 1-12. 54. LAL TEKRIWAL, K. & ARUNAVA RAO, A. (1999). Ornamental Aquarium Fish of India. Kingdom Books, United Kingdom. 55. LAWLER, J.J., WHITE, D., SIFNEOS, J.C. & MASTER, L.L. (2003) Rare species and the use of indicator groups for conservation planning. Conservation Biology, 17, 875–882. 56. LINKE, S., PRESSEY, R.L., BAILEY, R.C. & NORRIS, R.H. (2007) Management options for river conservation planning: condition and conservation re-visited. Freshwater Biology, 52, 918. 57. MARTIN, P., HANIFFA, M.A. & ARUNACHALAM, M. (2000). Abundance and diversity of macroinvertebrates and fish in the Tamiraparani river, South India. Hydrobiologia, 430, 59-75. 58. MAITLAND, P.S. (1995) The conservation of freshwater fish: past and present experience. Biological Conservation, 72, 259–270. 59. MENON, A.G.K. (1987). The Fauna of India and the adjacent countries – Pisces, Vol. IV. Teleostei – Cobitidae, Part I: Homalopteridae. Zoological Survey of India, Kolkata, India. 60. MILLER, E. & MURUGAN KANI, N. (2004). Cultivating a forest language: Development ideas for Kani tribal people of Tamil Nadu’s Kanniyakumari district. Proceedings of the First All-India Conference of the Kanniyakumari Academy of Arts and Sciences (KAAS), Nagercoil. 61. MINNS, C.K., KELSO, J.R.M. & RANDALL, R.G. (1996) Detecting the response of fish to habitat alterations in freshwater ecosystems. Canadian Journal of Fisheries and Aquatic Sciences, 53, 403–414. 62. MYERS, N., MITTERMIER, R.A., MITTERMIER, C.G., DA FONSECA, G.A.B., & KENT, J. 2000. Biodiversity hotspots for conservation priorities. Nature, 403, 853-858. 63. NAIR, S.C. 1991. Southern Western Ghats. Indian National Trust for Art and Cultural Heritage (INTACH), New Delhi, India. 32


Do Protected Areas of India’s Western Ghats conserve fish diversity?

64. NEL, J.L., ROUX, D.J., MAREE, G., KLEYNHANS, C.J., MOOLMAN, J., REYERS, B., ROUGET, M. & COWLING, R.M. (2007). Rivers in peril inside and outside Protected Areas: a systematic approach to conservation assessment of river ecosystems. Diversity and Distributions, 13, 341-352. 65. PASCUAL, M., MACCHI, P., URBANSKI, J., MARCOS, F., RIVA ROSSI, C., NOVARA, M. & DELL’ARCIPRETE, P. (2002a) Evaluating potential effects of exotic freshwater fish from incomplete species presence– absence data. Biological invasions, 4, 101–113. 66. PETHIYAGODA, R. (1994) Threats to the indigenous freshwater fishes of Sri Lanka and remarks on their conservation. Hydrobiologia, 285, 189–201. 67. PETHIYAGODA, R. & KOTTELAT, M. (2005) A review of the barbs of the Puntius filamentosus group (Teleostei: Cyprinidae) of southern India and Sri Lanka. The Raffles Bulletin of Zoology, 12, 127–144. 68. R DEVELOPMENT CORE TEAM. (2008). R: A language and environment for Statistical Computing. Vienna, Austria. http://www.r-project.org. Accessed August 2008. 69. RAAGAM, P.M., & REMA DEVI, K. (2004). An overview of the hill trouts (Barilius spp.) of the Indian region. Zoos’ Print Journal, 20, 1847-1849. 70. RAGHAVAN, R., ANVAR ALI, P.H. & PRASAD, G. (2007). Need for a comprehensive reassessment of the conservation status of critically endangered (?) freshwater fishes of Kerala. Current Science, 92, 721723. 71. RAGHAVAN, R., PRASAD, G., ALI, P.H. & SUJARITTANONTA, L. (2007) ‘Boom and bust fishery’in a biodiversity hotspot–Is the Western Ghats losing its most celebrated native ornamental fish, Puntius denisonii Day? Current Science, 92, 1671. 72. RAGHAVAN, R., PRASAD, G., ALI, P.H. & PEREIRA, B. (2008) Fish fauna of Chalakudy River, part of Western Ghats biodiversity hotspot, Kerala, India: patterns of distribution, threats and conservation needs. Biodiversity and Conservation, 17, 3119–3131. 73. RICHTER, B.D., BRAUN, D.P., MENDELSON, M.A. & MASTER, L.L. (2003) Threats to imperiled freshwater fauna. Conservation Biology, 11, 1081–1093. 74. RODRIGUES, A.S.L., ANDELMAN, S.J., BAKARR, M.I., BOITANI, L., BROOKS, T.M., COWLING, R.M., FISHPOOL, L.D.C., DA FONSECA, G.A.B., GASTON, K. J., HOFFMANN, M., LONG, J.S., MARQUET, P.A., PILGRIM, J.D., PRESSEY, R.L., SCHIPPER, J., SECHREST, W., STUART, S.N., UNDERHILL, L.G., WALLER, R.W., WATTS, M.E.J., & YA, X. (2004). Effectiveness of the global protected area network in representing species diversity. Nature, 428, 640-643. 75. ROYLE, J.A., & DORAZIO, R. (2008). Hierarchical modeling and inference in ecology - the analysis of data from populations, metapopulations and communities. Academic Press, USA. 76. SARKAR, U.K., PATHAK, A.K. & LAKRA, W.S. (2008) Conservation of freshwater fish resources of India: new approaches, assessment and challenges. Biodiversity and Conservation, 17, 2495–2511. 77. SAUNDERS, D.L., MEEUWIG, J.J. & VINCENT, A.C.J. (2002) Freshwater protected areas: strategies for conservation. Conservation Biology, 16, 30–41. 78. SHEEBA, S. (1999) Certain Aspects of the Ecology of the Ithikkara River. Mahatma Gandhi University, Kottayam, India. URL: http://www.mgutheses.org./page/?q=T%201127&search=&page=3&rad=# Accessed 21/1/2010. 79. SHELDON, A.L. (1988) Conservation of stream fishes: patterns of diversity, rarity, and risk. Conservation Biology, 2, 149–156. 80. SILAS E.G. (1951). Fishes from the High Range of Travancore. Journal of the Bombay Natural History Society, 50, 323-330. 81. SINGH, K. (1998). Handbook of environment, wildlife and forest protection laws in India. pp 467, Natraj Publishers, New Delhi, India. 82. SPIEGELHALTER, D. J., THOMAS, A., BEST, N.G., & LUNN, D. (2007). WinBUGS Version 1.4.3 User Manual. MRC Biostatistics Unit, Cambridge, U.K. 33


Do Protected Areas of India’s Western Ghats conserve fish diversity?

83.

84.

85. 86. 87. 88.

89.

90.

34

SREEKANTHA, M.D., MESTA, D.K., RAO, G.R., GURURAJA, K.V. & RAMACHANDRA, T.V. (2007) Fish diversity in relation to landscape and vegetation in central Western Ghats, India. Current Science, 92, 1592–1603. SREEKANTHA, M.D., GURURAJA, K.V. & RAMACHANDRA, T.V. (2008). Nestedness pattern in freshwater fishes of the Western Ghats: an indication of stream islands along riverscapes. Current Science, 95, 1707-1714. SUSKI, C.D. & COOKE, S.J. (2007) Conservation of aquatic resources through the use of freshwater protected areas: opportunities and challenges. Biodiversity and Conservation, 16, 2015–2029. THOMAS, R. K. (2004). Habitat and distribution of hill-stream fishes of Southern Kerala (South of Palghat Gap). PhD Thesis, Mahatma Gandhi University, Kottayam, Kerala, India. VANNOTE, R.L., MINSHALL, G.W., CUMMINGS, K.W., SEDELL, J.R. & CUSHING, C.E. (1980). The River Continuum Concept. Canadian Journal of Fisheries and Aquatic Sciences, 37, 130-137. VASUDEVAN, K., KUMAR, A. & CHELLAM, R. (2006) Species turnover: the case of stream amphibians of rainforests in the Western Ghats, southern India. Marine, Freshwater, and Wetlands Biodiversity Conservation, 147–157. VÖRÖSMARTY, C.J., MCINTYRE, P.B., GESSNER, M.O., DUDGEON, D., PRUSEVICH, A., GREEN, P., GLIDDEN, S., BUNN, S.E., SULLIVAN, C.A., REIDY LIERMANN, C. & DAVIES, P.M. (2010) ‘Global threats to human water security and river biodiversity’. Nature, 467(7315), 555-561. WIKRAMANAYAKE, E.D. (1990). Conservation of Endemic Rain Forest Fishes of Sri Lanka: Results of a translocation experiment. Conservation Biology, 4, 32-37.


Do Protected Areas of India’s Western Ghats conserve fish diversity?

W

e sincerely thank Dr. Ajith Kumar, Course Director, Post Graduate Program in Wildlife Biology and Conservation, WCS-India, for his constant motivation, critical guidance and for being an ever-inspiring mentor since the beginning of the project. We thank Dr. Uma Ramakrishnan of the National Centre for Biological Sciences, for her interest in the project and for kindly providing an affiliation with her lab. Dr. Jagdish Krishnaswamy of ATREE, Bangalore and Dr. Geoff Hyde of NCBS provided timely advice and suggestions regarding sampling methodology and scientific communication, respectively. Dr. A. Bijukumar of the Department of Aquaculture and Fisheries, University of Kerala, patiently helped us identify any doubtful specimens, answered every odd query, and even lent his books and equipments for fieldwork. Dr. Kurian Mathew Abraham of Mar Thoma College, Thiruvalla, was constantly supportive of our work, and a great companion in the field. The Kerala Forest Department gave timely permits for all field work. We are most grateful to the Principal Chief Conservator of Forests (Wildlife), Kerala, the Chief Conservator of Forests (Wildlife & Biodiversity), and the DFOs of each Wildlife Sanctuary and Reserve Forest in Thiruvananthapuram and Kollam district, for facilitating our entry inside the Protected Areas: Mr. P. I. Pradeep Kumar (Shenduruney WLS), Mrs. Girija (Peppara WLS) and Ms. Rohini (Kallar RF). Ms. Rohini, Mr. Jyothi (Neyyar WLS) and Mr. Pradeep Kumar are particularly thanked for their constant encouragement, interest, and for providing us with knowledgeable field assistants. Ms. Rini of the Kerala Forest Headquarters, Thiruvananthapuram, gave us updates on the permit processing patiently. Mr. Purushottam of the National Centre for Biological Sciences, Bangalore and Mr. Jose Alexander, State Bank of India, Thiruvananthapuram ensured smooth management of our funds. Praveen Muralidharan Pillai helped us in many ways in logistics, including giving his vintage jeep for fieldwork. Mr. C.T. Varghese kindly provided us with contacts throughout the landscape,

and always encouraged the work. Chacko, Ajimon, Francis, Chandrankutty, Sukumaran and Thomas Ammavan provided us with excellent help in the field, and we shared some memorable sightings in the Agasthyamala forests. Mr. Rajan M. provided us with a room during the project period. Mr. Vijaykumar, Mr. Pachha Ravi, Mr. Sreekuttan, Mr. Shobhana Das, Mr. Kuriakose Abraham, Mr. Sali, Mr. Aruviyode Surendran, Mr. Jayan Manikuttan, helped us with field logistics providing places to stay. Dr. Rajeev Raghavan, Fibin Baby, and Dr. P.H. Anvar Ali of Conservation Research Group, Kerala provided us with useful literature, references and suggestions with use and maintenance of nets. We were fortunate to interact with ecologists and taxonomists like Dr. Satheesh Chandran Nair, Dr. Shanthi Nair, Dr. E. Kunhikrishnan, Dr. C.P. Shaji, Dr. Sanjeev Ghosh, Dr. Sanjay Molur, Dr. Sheeba, Dr. R.J. Ranjit Daniels, Dr. Neelesh Dahanukar, Dr. Robin Vijayan, Dr. Devaka Weerakoon, and Dr. Anuradha Bhat. Mr. M.C. Kiran of ATREE provided us with DEM files of the landscape. Ms. Sigy Susan George (New Zealand) helped us by donating invaluable equipment for fieldwork. Dr. Abraham Kurian and family; and Mr. K.K. George and family, tolerated us throughout the work and always provided full support to the work. We thank Dr. K. Ullas Karanth and Dr. Ravi Chellam for their encouragement. Dr. R. Sukumar and Jisha analyzed our water quality samples at the Regional Research Laboratory, (NIIST-CSIR), Thiruvananthapuram. Vicky Lakshmanan, Roberto Caceres, Nikhil James, and Smrithiraj provided great company in field. Aathira Perinchery and Veena P.G. helped with various things. We also thank friends from the M.Sc. Program in Wildlife Biology and Conservation, and Dr. Uma Ramakrishnan’s lab (Lab-3) at NCBS, Bangalore and friends from the Conservation Leadership Program workshops and meetings in China. The sharing of information and experiences about their projects will be ever-invaluable. Finally, we express sincere gratitude towards Robyn, Lynn, Kiragu and Stuart, the CLP team, for their support, guidance and patience with our project. 35


Do Protected Areas of India’s Western Ghats conserve fish diversity?

Appendix 1. Annotated checklist of species sampled during the study. Taxonomy follows Eschmeyer and Fong (2010). Genus Species Author

Preferred Elevation Habitat Range

Chanda nama Hamilton 1822 Ru m Parambassis thomassi (Day 1870) Ru m Pseudambassis ranga (Hamilton 1822) Ru m Anguilla bengalensis (Gray 1831) Ru, Pl l,m,h Aplocheilus lineatus (Valenciennes 1846) Pl l,m Aplocheilus blockii (Arnold 1911) Pl m Horabagrus brachysoma (Günther 1864) Pl l,m Mystus bleekeri (Day 1877) Pl m, h Mystus malabaricus (Jerdon 1849) Pl m, h Mystus oculatus (Valenciennes 1840) Ru, Pl m Bhavania australis (Jerdon 1849) Ra h Travancoria jonesi Hora 1941 Ra, Ri h Nemacheilus guentheri Day 1867 Ra, Ru, Ri h Nemacheilus triangularis Day 1865 Ra, Ru, Ri m,h Lepidocephalichthys thermalis (Valenciennes 1846) Ra, Ru, Ri m,h Xenentodon cancila (Hamilton 1822) Ru, Pl l,m Channa gachua (Hamilton 1822) Ru, Pl l,m Channa marulius (Hamilton 1822) Ru, Pl l,m Channa striata (Bloch 1793) Ru, Pl l,m Channa diplogramma ^ (Day 1865) Ru, Pl m Etroplus maculatus (Bloch 1795) Ru, Pl l,m Etroplus suratensis (Bloch 1790) Ru, Pl l Oreochromis mossambicus (Peters 1852) Ru, Pl l,m Clarias dussumieri Valenciennes 1840 Pl m Heteropneustes fossilis (Bloch 1794) Pl l,m Dayella malabarica (Day, 1873) Ru m Salmophasia balookee (Sykes 1839) Ru m Devario cf. aequipinnatus (McClelland 1839) Ru, Pl l,m,h Devario malabaricus (Jerdon 1849) Ru, Pl l,m,h Rasbora daniconius (Hamilton 1822) Ru, Pl l,m,h 36

Occurence in Rivers KLD KLD, VAM, KAR, NEY KLD, KAR, NEY KLD, ITK, VAM, KAR, NEY KLD, ITK, VAM, KAR, NEY NEY KLD, KAR, NEY NEY KLD, ITK, VAM, KAR, NEY NEY KLD KLD, VAM NEY KLD, VAM, KAR, NEY KLD KLD, ITK, VAM, KAR, NEY VAM VAM, KLD KLD, ITK, VAM, KAR, NEY KLD KLD, ITK, VAM, KAR, NEY KLD, ITK, VAM, KAR, NEY NEY, KLD KLD, NEY NEY KLD NEY KLD, ITK, VAM, KAR, NEY KLD, ITK, VAM, KAR, NEY KLD, ITK, VAM,

Occurence in PAs/Non-PAs NPA NPA NPA PA, NPA PA, NPA NPA PA, NPA NPA PA, NPA NPA NPA PA PA PA, NPA PA NPA PA PA, NPA NPA PA PA, NPA NPA PA, NPA PA, NPA PA NPA NPA PA, NPA PA, NPA PA, NPA


Do Protected Areas of India’s Western Ghats conserve fish diversity?

Amblypharyngodon melettinus (Valenciennes 1844) Ru l,m Barilius bakeri Day 1865 Ra, Ru m, h Cyprinus carpio Linnaeus 1758 Pl m Tor malabaricus (Sykes 1839) Pl m, h Garra mcclellandi + (Jerdon 1849) Ra, Ru h Garra mullya (Sykes 1839) Ra, Ru, Pl, Ri l, m, h Garra hughi Silas 1955 Ra, Ru, Pl, Ri h Hypselobarbus curmuca (Hamilton 1807) Ru, Pl m, h Hypselobarbus kolus (Sykes 1839) Ru, Pl m Hypselobarbus kurali Menon & Ru, Pl m Rema Devi 1995 Osteobrama bakeri (Day 1873) Ru, Pl m Puntius mahecola (Valenciennes, 1844) Ru, Pl m Puntius dorsalis (Jerdon 1849) Ru, Pl m, h Puntius exclamatio Pethiyagoda & Ru, Pl m Kottelat 2005 Puntius fasciatus (Jerdon 1849) Ru, Pl, Ri m, h Puntius filamentosus (Valenciennes 1844) Ru, Pl m Puntius sp. novo. * Ru, Pl m Puntius jerdoni + (Day 1870) Ru, Pl m Puntius parrah Day 1865 Ru, Pl m Puntius narayani (Hora 1937) Ru, Pl m, h Puntius sarana (Hamilton 1822) Ru, Pl l, m Puntius ticto (Hamilton 1822) Ru, Pl, Ri m Sicyopterus griseus (Day 1877) Ru l, m Awaous gutum Talwar & Jhingran, 1991 Ru l, m Glossogobius giuris (Hamilton 1822) Ru l, m Hyporamphus limbatus Valenciennes, 1847 Ru, Pl l Mastacembelus armatus (Lacepède 1800) Ru, Pl, Ri l, m, h Pristolepis marginata Jerdon 1848 Ru, Pl l, m Ompok bimaculatus (Bloch 1794) Ru, Pl m, h Ompok malabaricus (Valenciennes 1840) Ru, Pl m, h

KAR, NEY NEY KLD, ITK, VAM, KAR, NEY KLD, NEY KLD, VAM, KAR, NEY NEY KLD, ITK, VAM, KAR, NEY VAM, NEY KLD, ITK, VAM, KAR, NEY KLD KLD

PA PA

KLD KAR, NEY KLD, ITK, VAM, NEY KLD

NPA NPA PA, NPA PA

KLD, VAM, KAR, NEY KLD, ITK, VAM, KAR, NEY ITK KLD KAR KLD KLD, ITK, NEY KLD, ITK, KAR, NEY KAR KAR KLD, ITK, VAM, KAR KLD KLD, NEY KLD, NEY NEY NEY, KLD

PA, NPA PA, NPA

NPA PA, NPA PA PA PA PA, NPA PA PA, NPA

NPA PA NPA PA PA, NPA PA, NPA NPA NPA NPA NPA PA, NPA PA, NPA PA, NPA PA, NPA

Key: Author names not in brackets indicate original descriptions unchanged. Names in brackets indicate redescriptions. Rivers: KLD – Kallada, ITK – Ithikkara, VAM – Vamanapuram, KAR – Karamana, NEY – Neyyar. PA – Protected Area, NPA – Non-Protected Area, Elevation range: l – low, m – mid, h – high. * - Abraham et al. In Preparation, so still not a valid species. + – Range extension to the Ashambu Hills Landscape, ^ - Taxonomy follows new molecular study showing that the Indian species of Giant Snakehead, previously Channa micropeltes should be treated as a distinct species C. diplogramma (Adamson et al. 2010). Preferred Habitat: Ru – Run, Ri – Riffle, Ra – Rapid, Pl – Pool.

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Do Protected Areas of India’s Western Ghats conserve fish diversity?

Appendix 2. IUCN Red List Status of freshwater fish species known from the Ashambu Hills landscape. The checklist is derived from previous literature (Biju et al. 2000, Easa and Shaji 2003, Thomas 2004) and updated by current knowledge. The IUCN assessment data has been compiled from CAMP (1997). Assessments for the present year (2010) are underway, and Robin Kurian Abraham is assessing many species included in this list. Family Genus Species Ambassidae Chanda nama Ambassidae Parambassis dayi Ambassidae Parambassis thomassi Ambassidae Pseudambassis ranga Anabantidae Anabas testudineus Anguillidae Anguilla bengalensis Anguillidae Anguilla bicolor Aplocheilidae Aplocheilus lineatus Aplocheilidae Aplocheilus blockii Bagridae Batasio travancorica Bagridae Horabagrus brachysoma Bagridae Mystus armatus Bagridae Mystus bleekeri Bagridae Mystus cavasius Bagridae Mystus keletius Bagridae Mystus malabaricus Bagridae Mystus montanus Bagridae Mystus oculatus Bagridae Mystus vittatus Balitoridae Bhavania australis Balitoridae Travancoria jonesi Balitoridae Nemacheilus denisoni Balitoridae Nemacheilus guentheri Balitoridae Nemacheilus pulchellus Balitoridae Nemacheilus triangularis Balitoridae Pangio goaensis Balitoridae Lepidocephalichthys thermalis Belonidae Xenentodon cancila Channidae Channa gachua Channidae Channa marulius Channidae Channa striata Channidae Channa diplogramma Cichlidae Etroplus maculatus Cichlidae Etroplus suratensis Cichlidae Oreochromis mossambicus Clariidae Clarias dussumieri Clariidae Heteropneustes fossilis Clupeidae Dayella malabarica Cyprinidae Laubuca dadyburjori 38

IUCN (1997 CAMP) Endemism Status VU EN WG VU WG DD VU EN EN LC DD EN WG EN WG LC VU LC DD EN WG VU LC VU EN WG EN WG DD WG DD WG DD WG LC WG DD LC DD VU LC LC CR WG LC DD * VU WG VU LC WG DD WG

Main Threats HL HL HL, DY, IN HL HL, IN, DY HL HL HL HL HL, DY HL, DY HL HL HL HL HL, DY HL HL HL HL HL HL HL HL HL HL, DY HL, DY, IN HL, DY, IN HL, DY HL, DY, OF HL, DY HL, DY HL, OF, IN HL, DY HL HL


Do Protected Areas of India’s Western Ghats conserve fish diversity?

Cyprinidae Cyprinidae Cyprinidae Cyprinidae Cyprinidae Cyprinidae Cyprinidae Cyprinidae Cyprinidae Cyprinidae Cyprinidae Cyprinidae Cyprinidae Cyprinidae Cyprinidae Cyprinidae Cyprinidae Cyprinidae Cyprinidae Cyprinidae Cyprinidae Cyprinidae Cyprinidae Cyprinidae Cyprinidae Cyprinidae Cyprinidae Cyprinidae Cyprinidae Cyprinidae Cyprinidae Cyprinidae Cyprinidae Cyprinidae Cyprinidae Cyprinidae Cyprinidae Cyprinidae Cyprinidae Cyprinidae Cyprinidae Cyprinidae Cyprinidae Cyprinidae Cyprinidae Cyprinidae Cyprinidae Cyprinidae

Salmophasia Salmophasia Esomus Esomus Devario Devario Rasbora Amblypharyngodon Amblypharyngodon Barilius Barilius Barilius Cyprinus Ctenopharyngodon Osteobrama Labeo Labeo Labeo Tor Catla Cirrhinus Garra Garra Garra Garra Horalabiosa Hypselobarbus Hypselobarbus Hypselobarbus Osteobrama Puntius Puntius Puntius Barbodes Puntius Puntius Puntius Puntius Puntius Puntius Puntius Puntius Puntius Puntius Puntius Puntius Puntius Puntius

boopis balookee danricus thermoicos cf. aequipinnatus malabaricus daniconius melettinus microlepis bakeri bendelisis gatensis carpio idella bakeri dussumieri rohita calbasu malabaricus catla mrigala mcclellandi mullya hughi surendranathanii joshuai curmuca kolus kurali bakeri mahecola arulius bimaculatus carnaticus chola conchonius denisonii dorsalis exclamatio fasciatus filamentosus sp. nov jerdoni parrah narayani sarana tambraparniei ticto

LC WG EN VU DD LC LC WG DD LC DD VU WG LC DD WG * * EN WG EN WG LC LC VU WG * * EN WG LC EN WG DD WG DD EN WG EN WG EN WG DD WG NT WG EN DD VU WG VU VU EN WG EN VU WG-Ash EN WG DD DD WG-Ash EN EN DD WG LC WG CR WG LC

HL, DY HL, DY

HL HL HL HL, DY HL HL, EX HL HL

HL HL, EX HL HL HL, OF, DY, EX

HL, DY, EX HL, DY, EX HL HL HL, EX HL,OF,DY,EX,IN HL, DY HL, DY HL, DY, IN HL, IN HL HL, DY, IN HL HL, DY, IN HL, DY, IN HL, DY, OF HL, DY HL, EX, DY HL, DY HL, DY, IN HL HL, EX, DY HL HL, EX, DY HL, OF, IN, DY HL HL, EX, DY, IN 39


Do Protected Areas of India’s Western Ghats conserve fish diversity?

Cyprinidae Gobiidae Gobiidae Gobiidae Hemirhamphidae Mastacemelidae Mastacemelidae Nandidae Notopteridae Osphronemidae Siluridae Siluridae Siluridae Sisoridae Sisoridae Synbranchidae Syngnathidae Tetraodontidae

Puntius Sicyopterus Awaous Glossogobius Hyporamphus Mastacembelus Macrognathus Pristolepis Notopterus Pseudosphromenus Ompok Ompok Wallago Glyptothorax Glyptothorax Monopterus Microphis Carinotetraodon

vittatus griseus gutum giuris limbatus armatus guentheri marginata notopterus cupanus bimaculatus malabaricus attu annandalei madraspatanus fossorius cuncalus travancoricus

VU DD DD LC DD LC VU VU WG LC DD EN CR WG LC EN VU WG EN VU EN WG

HL HL HL HL, DY, IN HL HL, OF, DY, IN HL, DY HL, DY HL HL, DY HL, DY HL, DY, EX HL, DY, OF HL HL HL, OF, DY HL HL, OF

Key: IUCN Status: LC – Least Concern, NT – Near Threatened, VU – Vulnerable, EN – Endangered, CR – Critically Endangered, DD – Data Deficient, * – Exotic Species. Endemism: WG – Western Ghats, WG-Ash – Ashambu Hills. Threats: HL – Habitat Loss, DY – Dynamite Fishing, OF – Overfishing, EX – Exotic species, IN – Industrial Pollution.

Appendix 3. Land-use changes in the five river basins of the Ashambu Hills landscape over the last 20 years. Neyyar: Expansion of Neyyatinkkara town, declaration of the Neyyar WLS, changes in Kani settlements inside Neyyar WLS, electric power-lines entering the forest area for Kani settlers, increase in check dams, extension of agriculture, roads, trek-paths within WLS, opening up of forest in Sanctuary area. Karamana: Construction of Aruvikkara dam and reservoir, Increase in coconut plantations, Kottur Reserve Forest changed to exotic Acacia plantations, large increase in industrial units, mixed agriculture, vast expansion of settlements and agriculture, reduction of forest. Vamanapuram: Increase in exotic Acacia plantations, roads. Ithikkara: Large increase in area under rubber plantations, increased area of oil palm plantations around Palode/Yeroor Reserved Forests. Kallada: Increase in mixed agriculture, rubber plantations.

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Do Protected Areas of India’s Western Ghats conserve fish diversity?

Key Threats to Freshwater Fish inside Protected Areas 1. Regular introduction of large sized Exotic Species into dam reservoirs by the Fisheries Department, which negatively impact indigenous native species of fish and other aquatic organisms 2. Disposal of plastic refuse and irresponsible disposal of liquor bottles (often by smashing them on rocks near streams) inside Wildlife Sanctuaries and Reserve Forests by tourists and pilgrims, many of whom carry these with them, especially on the Agasthyamala trek route and in Ponmudi Hill Station. 3. Illegal fishing inside Wildlife Sanctuaries and Reserve Forests by Forest Department ground staff like watchers and contract labourers who clear fire lines and trek paths, regularly, along with fishermen accessing PA streams via dam reservoirs.

The Common/Eurasian Carp (Cyprinus carpio), an introduced species that aggressively out-competes native and endemic species. Studies from other countries where thay have been introduced have documented the vast damage caused by this species to aquatic ecosystems and native fishes. Hence, it would be illogical to assume that such exotic species have any long term benefit in our landscape.

Tilapia (Oreochromis mossambicus), an exotic species from Africa has succesfully colonozed most freshwater habitats in the Indian peninsula and is an aggressive competitor with many native fish species.

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Do Protected Areas of India’s Western Ghats conserve fish diversity?

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Design Concept & Layout by Robin Kurian Abraham


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