Amphibian communities in
three different coffee plantation regimes in the Western Ghats, India
Shradha Rathod 1 & Pooja Rathod 2
1 Durrell Institute of
Conservation and Ecology University of Kent, Canterbury CT27NR, United Kingdom
1 Current address: A/33, Suparshwanath Society, Market Yard Road, Pune, Maharashtra
411037, India
2 National Centrefor Biological Sciences, Tata Institute of Fundamental Research, Bengaluru,
Karnataka 560065, India
1 shradha.rathod@gmail.com (corresponding author), 2 poojarathod90@gmail.com
doi: http://dx.doi.org/10.11609/JoTT.o3054.4404-13 | ZooBank:urn:lsid:zoobank.org:pub:D7423DD8-B6CB-421F-8B01-8BA4881329FF
Editor: Sanjay Molur,
ZOO|WILD, Coimbatore, India Date
of publication: 26 May 2013 (online & print)
Manuscript details: Ms # o3054 | Received 04 January 2012 | Final
received 15 February 2013 | Finally accepted 06 May 2013
Citation: Rathod,
S. & P. Rathod (2013). Amphibian
communities in three different coffee plantation regimes in the Western Ghats,
India. Journal of Threatened Taxa 5(9): 4404–4413; http://dx.doi.org/10.11609/JoTT.o3054.4404-13
Copyright: © Rathod& Rathod 2013. Creative Commons
Attribution 3.0 Unported License. JoTT allows unrestricted use of this article in any medium,
reproduction and distribution by providing adequate credit to the authors and
the source of publication.
Funding: Durrell Institute of Conservation and
Ecology, University of Kent, Canterbury, United Kingdom.
Competing Interest: None.
Acknowledgements: We thank Durrell Institute of Conservation and Ecology (DICE) for funding this project. We appreciate the logistical support
provided by Drs. Sujata and Anurag Goel and several coffee estate owners who welcomed us to work in their plantations. We are
grateful to A. Michael for his invaluable assistance during fieldwork. We thank Dr. R. Griffiths for providing valuable inputs, support and guidance throughout this project and Dr. J. Groombridgefor help during analysis. We are grateful to R. Raghavanand A. Zambre for their critical comments, help, enthusiasm and belief in the project. We also thank S.D. Biju and S.P. Vijaykumar for
their valuable comments.
Abstract: In the highly populated and diverse tropics, conservation in
relatively pristine habitats is important but clearly inadequate for sustaining
the earth’s biological diversity. Agro-forestry systems such as shade-coffee plantations that incorporate
arboreal vegetation are known to be more resilient for biodiversity
conservation than other more drastic land transformations. We evaluated amphibian richness and
diversity in 15 coffee plantations from three different regimes; organic coffee
plantations, NPK coffee plantations and pesticide use coffee plantations in Kodagu District, Western Ghats, India. We treated five sacred groves as control
region (CR) and sampled them using a combination of standardized visual and
acoustic transect sampling. The sacred groves that were characterized by
natural vegetation showed the highest richness and abundance of amphibians
among the four regimes. In organic
coffee plantations, overall abundance and richness of amphibians was
significantly higher compared to NPK coffee plantations. On the other hand, amphibian richness
and diversity in pesticide use coffee plantations were significantly lower
compared to all other regimes. The
results of the study clearly indicated that, the difference in habitat
variables in coffee plantations and use of different treatments for pest
control had a significant effect on the species richness and abundance of
amphibians. This study highlights
the great potential of sacred groves and organic coffee plantations as
complementary habitat for the conservation of amphibians.
Keywords: Agro-forestry,
conservation, organic, pesticides, sacred groves, shade coffee.
For figures, images, tables -- click here
In
a matrix of human-modified habitats showing multiple land use types, forest
reserves are increasingly becoming isolated islands. These human modified landscapes are
taking over the native forest and now form a significant amount of the earth’s
land surface (Bali et al. 2007). In
the highly populated and diverse tropics, conservation in relatively pristine
habitats is important but clearly inadequate for sustaining the earth’s biological
diversity (Janzen 1998; Daily et al. 2003). Agro forestry systems or plantation
crops that incorporate arboreal vegetation are known to be more resilient for
biodiversity conservation than other more drastic land transformations (Dolia et al. 2008). Therefore, prospects of conservation in structurally complex habitats
like these should be given preference. Natural-shade coffee plantations are one of the classic examples of such
a system (Perfecto et al. 1995, 1996; Moguel &
Toledo 1999; Rice & Greenberg 2000; Kapoor 2007; Dolia et al. 2008).
During
the last century, the Western Ghats, a biodiversity hotspot (Myers et al. 2000)
in peninsular India (Fig. 1) had undergone massive fragmentation due to
multiple anthropogenic pressures. The southern Western Ghats were once characterized by vast expanses of
tropical rainforest, but are now strewn with plantations of Tea Camellia sinensis, Coffee Coffeaspecies, Rubber Hevea brasiliensis and
Cardamom Elettaria cardamomum (Daniels et al. 1990; Chandran 1997). This has resulted in an approximately
40% loss of the natural vegetation and a four-fold increase in the number of
forest fragments in the Western Ghats (Menon & Bawa 1997). Coffee plantations covering an area of approximately 3,500km are one of
the major competitors for land in the Western Ghats (Ninan& Sathyapalan 2005). The effects of tropical forest
fragmentation and the biodiversity value of shade-grown coffee have been
explored for various taxa such as mammals, plants, birds (Turner 1996; Perfecto
et al. 1996, 2003) and insects (Perfecto & Vandermeer2002). Studies on the effects of coffee agro-ecosystems on amphibians are
limited, and have been mainly restricted to inventories in Central and South
America (Pineda & Halffler 2004; Pineda et al.
2005). There has been a paucity of
ecological research on amphibians, which is surprising given the fact that they
are diverse and abundant, easily sampled and functionally significant. The ways in which they interact with
their biotic and abiotic environment can reflect ecological changes (Noss 1990; Hill 1995) and therefore this group is promoted
as a strong bioindicator of environmental stress
(Carey & Bryant 1995; Welsh & Ollivier 1998; Blaustein et al. 2003).
Coffee
was introduced in India in the 1740s and since then it has been grown
extensively by replacing the large native patches of wet-evergreen, mid
elevation and moist deciduous forests in the southern Western Ghats which have
been known to harbour extremely diverse endemic
amphibian fauna (Daniels 1992; Das et al. 2006). In contrast to the clear
felling followed by plantations of monoculture coffee in Central and South
America, plantations of coffee and cardamom in the Western Ghats involve
clearing of only the undergrowth leaving most of the native trees (canopy
cover) intact. However, in recent years these native trees are gradually being
replaced by the exotic, fast growing Silver Oak Grevillea robusta for economic benefits (S. Biju pers. comm. June 2012). This conversion from traditional to
modern coffee cultivation has been considered a significant driver of
biodiversity loss (Rappole et al. 2003).
Shade-coffee
plantations in the southern Western Ghats fall under three different regimes:
(a)
Organic coffee plantations (OCP’s) follow standards and techniques that
prohibit the use of herbicides, fertilizers and pesticides. This practice manifests the protection
of crops against diseases at an ecological level by stimulating the natural defences of plants themselves and through natural predation
of pests wherein the native plant species are colonized by parasitic insects
and play a significant role in controlling pest population. This practice also
incorporates socially responsible activities such as environmental protection,
recycling, and soil health.
(b)
NPK coffee plantations (NCP’s) use nitrogen (N), phosphorus (P) and potassium
(K) that are commonly used in fertilizers. They also use fungicides like Bordeaux mixture, which is a combination
of copper sulphate and hydrated lime.
(c)
Pesticide using coffee plantations (PCP’s) use pesticides such as chlorpyrifos, diazinon, disulfoton, methyl parathion, triadimefon,cypermethrin etc., for controlling major pests and
pathogens. Locally these pesticides
are sprayed no less than twice a year, in winter and post-monsoon.
(d)
We sampled sacred groves as a control region (CR) for the current study. Sacred groves are patches of native
forest that are interspersed among coffee plantations. These groves are patches of intact
natural vegetation that are maintained by local communities where activities
like hunting, logging or any kind of habitat modifications are strictly
prohibited (Viswanath 2003).
Pesticide using coffee plantations make use of large amounts of pesticides to
prevent damage from a multitude of pests (e.g., white stem borer, berry borer)
and diseases (e.g., leaf rust and black rot) along with intensive shade
lopping. Craves (2011) reports
that, even though many chemicals that have been found to be harmful to the
environment have been banned or are strictly regulated in the United States of
America or Europe, they remain legal to be used in many less developed
countries that grow coffee. These
practices pose a serious threat to the existing amphibian fauna in the region (Gurushankara et al. 2007). Amphibians with their highly sensitive
skin, bimodal life, complex life history and varied reproductive strategies
(Lips 1998), tend to be highly susceptible to chemical contaminations (Pogorzeiska et al. 1982; Harris et al. 1998; Schiesari et al. 2007). The effects of environmental pollutants,
particularly pesticides on amphibian communities have been of significant
conservation interest for the past few decades. The responses of amphibian species can
be strong but at the same time different to varying degree of landscape
fragmentation and chemical pollutants like pesticides. For example, a preliminary investigation
by Daniels (2003) suggests that despite the apprehensions about possible
environmental contamination, tea estates tend to support a reasonably high
diversity of amphibians in the southern Western Ghats. Hence, a thorough understanding of their
responses to habitat modifications is indispensable for their long term conservation. The major aim of this study was to assess the effects of three different
coffee plantation regimes on amphibian communities. The specific questions addressed were:
(a)
Does the use of different regimes influence the species richness, relative
abundance and community composition of amphibians in coffee plantations?
(b)
Are some species affected more disproportionately than others?
(c)
What other factors possibly influence amphibian assemblages in coffee
plantations?
Materials and Methods
Study site
This study was conducted in
June–July 2011 in Kodagu District (11056’–12052’N
& 75022’–76011’E) of Karnataka State, in the
Western Ghats, India. Elevation of Kodagu ranges from
900 to 1750 m, and the area receives intense rainfall in the months of July and
August. The annual rainfall ranges
from 1500–4500 mm and is highly variable due to the topography of the
region. Temperature ranges from
11–28 0C. During
the sampling period, monsoon had already set in and there was heavy rainfall
throughout the study. Data was collected from coffee plantations and sacred
groves that are spread across Kodagu District. Coffee was intercropped with Cardamom Elettaria cardomomum,
Vanilla Vanilla planifoliaand Pepper (Piper species). Shade-grown coffee plantations occupy
approximately 60% of the landscape in Kodagu (Bhagwat et al. 2005). Ficus glomerata, Artocarpus integrifolia, Erythrina lithosperma and Albizia lebbeck are some native tree species commonly
used as shade for coffee. However, these native species are being increasingly replaced by
Silver Oak (S. Goel pers. comm. July
2011). We selected 15 coffee plantations
and five sacred groves as sampling units.
Coffee plantations
The coffee plantations ranged
30–200 acres in area and fell within altitudes ranging 800–1200
m. A quadrate of 80×50 m was
placed using a rope in each plantation in order to incorporate maximum
microhabitats used by amphibians. A
combination of visual encounter surveys (VES) and acoustic encounter surveys
(AES) (Rödel & Ernst 2004) were conducted within
each quadrate in order to estimate amphibian species richness and species composition
of the local assemblage. In order to avoidconfounding effects due to edge, each quadrate was set at least 50–80 m
from the edge. Each survey was
carried out for a period of 120 minutes (excluding the time for
identification), 1800–2000 hr in order to
estimate amphibian abundance per unit time.
Sacred groves
The vegetation in sacred
groves was dense and predominantly moist-deciduous with tall trees that formed
the canopy. This was unlike coffee
plantations that are short and hence amphibians could be visually
detected. To overcome this problem
we used a combination of standardized visual (SVTS) and acoustic (SATS)
transect sampling (Rödel & Ernst 2004). A 100m
transect was surveyed in each sacred grove and amphibian calls within 5m on
either side of the transect were recorded in addition
to the individuals visually encountered on the ground. Transects were walked between 1800 and
2000 hr with sampling duration of 120 minutes to
estimate amphibian abundance per unit time. All observations were made
by two observers assisted by a field assistant. All micro-habitatssuch as foliage, branches, tree barks, twigs, leaves were carefully
scanned. Leaf litter was thoroughly
searched and occasionally shifted and amphibians dispatched from the litter were
included in the sample.
Taxonomy
Amphibians were identified to
the genus and species levels using identification keys provided in Daniel
(2002), Biju & Bossuyt(2005, 2006, 2009), Biju et al. (2011), Kuramoto et al. (2007) and Zachariah et al. (2010, 2011).
Individual amphibians that could not be identified on site were caught,
identified and subsequently released in the same quadrat.
Microclimatic
variables
We
measured maximum and minimum air temperature and humidity at the start of
sampling each quadrate with a digital max/min thermo-hygrometer. Location of each sampling unit (quadrate
in each plantation) was recorded using a GPS (Garmin eTrexVista HCx) (Tables 1 & 2).
Analysis
Exploratory
data analysis was performed using SPSS version 18.0 (SPSS 2009). Parametric statistical tests such as
one-way analysis of variance (ANOVA) were used to see if species richness and
abundance differ significantly across the four regimes. Diversity of amphibian assemblages was
measured with the Shannon-Wiener index (H) and its respective evenness (EH). Using ANOVA, we compared the calculated
H-values and EH–values for the four regimes.
Results
A
total of 594 amphibians belonging to 22 species were recorded during this
study. We recorded 377 amphibians
using a combination of VES and AES in 30 hours of quadrate sampling in 15
coffee plantations and 217 amphibians using a combination of SVTS and SATS in
10 hours of transect sampling in five sacred groves. Out of these, 19 species were recorded
from organic coffee plantations, 15 species from NPK coffee plantations, 13
from pesticide using coffee plantations and 15 species from sacred groves
(Table 3).
Amphibian
species richness and abundance
Amphibian
species richness was significantly different in organic coffee plantations and
NPK coffee plantations, and the same way between organic coffee plantations and
sacred groves (F3,16= 8.105, P<0.002)
(Fig. 2a). Moreover, abundance of amphibians was influenced by the regimes as
there was a significant difference in the values between plantations (F3,16 = 26.443, P<0.001) (Fig. 2b and Fig.
3).
Shannon-Wiener
Diversity Index
Figure
2c represents Shannon’s diversity index (H). The results indicate that there is a
significant difference in the diversity across the four regimes (F3,16 = 12.165, P<0.001). The results of Shannon’s evenness index
(EH) was statistically insignificant (F3,16 = 1.957, P<0.161) indicating that individuals in the community are
distributed equitably among the species across the four regimes (Fig. 2d).
Discussion
The
current study was an attempt to understand species community level patterns of
amphibians within three different coffee growing practices. The results of this
study clearly indicates that the difference in habitat variables in
coffee plantations and use of different treatments for pest control had a
significant effect on the species richness and abundance of amphibians. Species
richness and abundance was highest in organic coffee plantations and decreased
in NPK and pesticide using plantations. We observed a high diversity of native rainforest trees in organic
coffee plantations. NPK coffee
plantations on the other hand, consist of mixed canopy of native and exotic
trees such as Maesopsis eminii,Bischofia javanica, Spathodes campanulata, Erythrina lithosperma, Ailanthus integrifolia and Ficusspp. However, pesticides using
coffee plantations were dominated by exotic monoculture of silver oak trees
resulting in decreased canopy cover. Decreasing canopy cover resulting in higher temperatures, decreasing
atmospheric humidity and increasing wind velocity (Saunders et al. 1991; Murcia
1995; Pineda & Halffter 2004) which could account
for the decreased species richness and abundance. The humidity levels recorded during the
current study show a decreasing trend as we go from OCP to NCP and PCP. Humidity levels in OCP and CR were
almost comparable. However, the
decline is not very pronounced; hence it will be difficult to draw any
conclusions (Fig. 4).
Species
composition often varies across different land use types and regimes and
species that require specific ecological conditions that are not available in
modified land uses may be more affected than others (Waltertet al. 2004). Presence of aquatic
habitats plays a key role in the maintenance of particular amphibian species (Neckel-Olivieira & Gascon2006). In the present study, the
complete absence of two species, Rhacophorus malabaricus and R. lateralisfrom NPK coffee plantations and pesticide using coffee plantations can be due
to an absence of aquatic habitats in these two coffee regimes. Hillers et al. (2008) reports that a
more open canopy can enhance higher temperatures and increased evaporation and
may reduce persistence of aquatic habitats. The organic coffee plantations sites had
natural as well as man-made aquatic pools, while sacred groves had natural
water bodies, which provided breeding sites for certain species within the
family Rhacophoridae. Generalist species like the Indian Bull
Frog Hoplobatrachus tigerinus(Daniels 2002) were also completely absent from NPK coffee plantations and
pesticide using coffee plantation regimes, which could again be a consequence
of unavailability of aquatic breeding sites.
Nyctibatrachus sp. and Ramanella sp. that
belong to the genera of forest dependent species endemic to the Western Ghats (Aravind & Gururaja 2011)
along with other terrestrial amphibians (Table 3) were completely absent from
pesticide using coffee plantations. These species could be most affected as planters in this regime
regularly use herbicides and practice manual de-weeding that causes disturbance
to understory vegetation. These practices may have negatively affected
terrestrial amphibians at various stages (eggs, juvenile, sub-adults and
adults) potentially leading to reduced fitness and recruitment. Gurushankaraet al. (2007) observed the highest incidence of morphological abnormalities in
populations of frogs inhabiting coffee plantations and suspected chemical
contamination (both fertilizer and pesticide) to be the cause. Absence of forest-dependent species of Nyctibatrachus sp. and Micrixalussp. from coffee plantations have also been reported by Krishna et al. (2005)
and Aravind & Gururaja(2011). Zakeranasp. was highest in abundance across all three regimes. According to Kuramoto et al. (2007), Zakerana are generalists that occur near still and stagnant water where they are
known to breed. Such habitats were
available throughout all coffee estates as the first order streams were
partially swampy due to open canopy and understory vegetation.
While
understanding the impact of coffee on species from the genus Raorchestes commonly known as bush frogs, it would
not be possible to treat species richness and life-history strategies
separately. For instance, species
from this genus have direct development (Biju 2003)
and thus provide little protection to the eggs, when coffee is sprayed with
pesticides. However, these species
have been able to survive in all three regimes and sacred groves. Although it cannot be entirely
explained, survival of the bush frog may partly be attributed to their breeding
period. Breeding takes place during
the wettest part of the year, whereas pesticides are sprayed during
post-monsoon and winter. As the bush
frogs stay dormant during these times of the year, probably under leaf litter
and barks, when most of the foliar applications of pesticides take place, they
may barely be exposed to pesticides directly.
Despite some clear patterns, the
present study had several limitations. It is representative only of the southwest monsoon season as it was carried out during June and July. Visibility also varied across the three
regimes, being highest in pesticide using coffee plantations, followed by NPK
and organic coffee plantations, then sacred groves, suggesting that the higher
richness and abundance in the latter may only be a
conservative estimate. Due to a
lack of accessibility, canopy species were completely omitted. Zakerana sp. could be identified only to the genus level hence,
we cannot comment on its species richness across the coffee estates and sacred
groves. A long-term study should be conducted in order to understand the
variables that drive the resulting patterns of this study.
Coffee
plantations as habitats for amphibians
This
study nevertheless highlights the great potential of organic coffee plantations
and sacred groves as complementary habitat for the conservation of
amphibians. However, certain
drawbacks of NPK coffee plantations and pesticide using coffee plantation
regimes like certain habitat variables and use of fertilizers and pesticides,
respectively, may prevent them from being an ideal habitat for amphibians. A study that compared morphological
abnormalities in natural populations of frogs inhabiting agro-ecosystems of
central Western Ghats showed that coffee plantations had the highest incidence
of abnormality that could have resulted due to the use of large amounts of
chemical fertilizers and pesticides (Gurushankara et
al. 2007). Further studies that
take into account pesticide use in coffee plantations may reveal additional
factors that influence community structure attributes like richness and
abundance of amphibians as well as their fitness in coffee plantations. Given
the Indian scenario, creating more inviolate spaces in the Western Ghats is
unlikely to win much support in the present economic and political context. This study coupled with other independent studies (Gray et al.
2004; Pineda et al. 2005; Bali et al. 2006; Kapoor2007; Dolia et al. 2008) suggest that,
promoting organic coffee plantation practices can have a greater positive
impact on biodiversity conservation. It is important to consider that these coffee dominated landscapes might
be the last refuge in modified landscapes for some highly endemic species. The present study forms a useful
baseline for agriculturists, as the decisions they take can dramatically affect
our biodiversity levels.
References
Aravind, N.A. & K.V. Gururaja (2011). Amphibians of the Western Ghats. Theme paper, Western Ghats Ecology Expert Panel, Ministry of
Environment and Forests, India.
Bali,
A., A. Kumar & J. Krishnaswamy (2007). The mammalian
communities in coffee plantations around a protected area in the Western Ghats,
India. Biological Conservation 139: 93–102; http://dx.doi.org/10.1016/j.biocon.2007.06.017
Bhagwat, S.A., C.G. Kushalappa, P.H. Williams & N.D. Brown (2005). A landscape approach to biodiversity
conservation of sacred groves in the Western Ghats of India. Conservation Biology 19:
1853–1862; http://dx.doi.org/10.1111/j.1523-1739.2005.00248.x
Biju. S.D. (2003). Reproductive mode in
the shrub frog Philautus glandulosus (Jerdon, 1853) (Anura: Rhacophoridae). Current Science 84(3): 283–284.
Biju, S.D. & F. Bossuyt (2005). New species of Philautus(Anura: Ranidae, Rhacophorinae) from Ponmudi Hill
in the Western Ghats of India. Journal of Herpetology 39:
349–353; http://dx.doi.org/10.1670/133-04A.1
Biju, S.D. & F. Bossuyt (2006). Two
new species of Philautus (Anura,Ranidae, Rhacophorinae)
from the Western Ghats, India. Amphibia-Reptilia 27: 1–9; http://dx.doi.org/10.1163/156853806776051985
Biju, S.D. & F. Bossuyt (2009). Systematics and phylogeny of Philautus Gistel, 1848 (Anura, Rhacophoridae) in the Western
Ghats of India, with descriptions of 12 new species. Zoological
Journal of the Linnean Society 155:
374–444; http://dx.doi.org/10.1111/j.1096-3642.2008.00466.x
Biju, S.D., I. van Bocxlaer, S. Mahony, K.P. Dinesh, C. Radhakrishnan,
A. Zachariah, V. Giri & F. Bossuyt(2011). A
taxonomic review of the Night Frog genus Nyctibatrachus Boulenger, 1882 in the Western Ghats, India (Anura: Nyctibatrachidae) with
description of twelve new species. Zootaxa 3029: 1–96.
Blaustein, A.R., J.M. Romansic,
J.M. Kiesecker & A.C. Hatch (2003). Ultraviolet radiation, toxic chemicals
and amphibian population declines. Diversity and Distribution 9:
123–140; http://dx.doi.org/10.1046/j.1472-4642.2003.00015.x
Carey, C. & C.J. Bryant (1995). Possible interrelations among
environmental toxicants, amphibian development, and decline of amphibian
populations. Environmental Health Perspectives 103: 13–17.
Chandran,
M.D.S. (1997). On
the ecological history of the Western Ghats. Current Science73: 146–155.
Craves,
J. (2011). Common
pesticides-Coffee and conservation. http://www.coffeehabitat.com/2006/12/pesticides_used_2/On-line
version dated 1 August 2011.
Daniels,
R.J. (2003). Impact of tea cultivation on anurans in the Western Ghats. Current Science 85: 1415–1422.
Daily, G.C., G. Ceballos,
J. Pacheco, G. Suzan & A. Sanchez-Azofeifa(2003).Countryside biogeography of neotropicalmammals: conservation opportunities in agricultural landscapes of Costa Rica. Conservation
Biology 17: 1814–1826; http://dx.doi.org/10.1111/j.1523-1739.2003.00298.x
Daniels, R.J.R., M. Hegde& M. Gadgil (1990). Birds of the man-made ecosystems: the
plantations. Animal Science 99: 79–89; http://dx.doi.org/10.1007/BF03186376
Daniels,
R.J.R. (1992). Geographical
distribution patterns of amphibians in Western Ghats, India. Journal of
Biogeography 19: 521–529.
Daniel,
J.C. (2002). The
Book of Indian Reptiles and Amphibians. Oxford University
Press, India, 248pp.
Das,
A., J. Krishnaswamy, K.S. Bawa,
M.C. Kiran, V. Srinivas,
N.S. Kumar & K.U. Karanth (2006). Prioritization of
conservation areas in Western Ghats, India. Biological Conservation 133: 16–31;http://dx.doi.org/10.1016/j.biocon.2006.05.023
Dolia, J., M.S. Devy,
N.A. Aravind & A. Kumar (2008). Adult butterfly communities
in coffee plantations around a protected area in the Western Ghats, India. Animal Conservation 26: 26–34; http://dx.doi.org/10.1111/j.1469-1795.2007.00143.x
Gurushankara, H.P., S.V. Krishnamurthy & V. Vasudev (2007). Morphological abnormalities in natural
populations of common frogs inhibiting agrosystems of
central Western Ghats. Applied Herpetology 4: 39–45
Harris,
M.L., C.A. Bishop, J. Struger, B. Ripley & J.P.
Bogart (1998). The functional integrity of northern Leopard Frog (Rana pipiens) and
Green Frog (Rana clamitans)
populations in Orchard wetlands. II. Effects of pesticides and eutrophic
conditions on early life stage development. Environmental Toxicology and
Chemistry 17: 1351–1363; http://dx.doi.org/10.1002/etc.5620170720
Hillers, A., M. Veith& M. Rodel (2008). Effects of forest
fragmentation and habitat degradation on West African Leaf-litter frogs. Conservation Biology 22: 762–772; http://dx.doi.org/10.1111/j.1523-1739.2008.00920.x
Hill,
G.E. (1995). Ornamental
traits as indicators of environmental health. BioScience 45: 25–31.
Janzen,
D. (1998). Gardenificationof wildland nature and the human footprint. Science279(5355): 1312–1313; http://dx.doi.org/10.1126/science.279.5355.1312
Kapoor, V. (2007). Effects of rainforest
fragmentation and shade-coffee plantations on spider communities in the Western
Ghats, India. Journal of Insect Conservation 12: 53–68; http://dx.doi.org/10.1007/s10841-006-9062-5
Kuramoto, M., S.H. Joshy, A. Kurabayashi & M.
Sumida (2007). The
genus Fejervarya (Anura: Ranidae) in central
Western Ghats, India, with descriptions of four new cryptic species. Current Herpetology 26(2):
81–105; http://dx.doi.org/10.3105/1881-1019(2007)26[81:TGFARI]2.0.CO;2
Lips, K.R. (1998). Decline of a tropical montane amphibian fauna. Conservation Biology12(1): 106–117; http://dx.doi.org/10.1111/j.1523-1739.1998.96359.x
Menon, S. & K.S. Bawa (1997). Applications
of geographical information system, remote sensing and a landscape ecology
approach to biodiversity conservation in Western Ghats. Current Science73: 134–145.
Moguel, P. & V.M.
Toledo (1999). Review: biodiversity
conservation in traditional coffee systems in Mexico. Conservation Biology13: 11–21; http://dx.doi.org/10.1046/j.1523-1739.1999.97153.x
Murcia,
C. (1995). Edge effects
in fragmented forests: implications for conservation. Trends in Ecology and
Evolution 10: 58–62; http://dx.doi.org/10.1016/S0169-5347(00)88977-6
Myers,
N., R.A. Mittermier, C.G. Mittermier,
G.A.B. da Fonseca & J. Kent (2000). Biodiversity hotspots for conservation
priorities. Nature 403: 853–858; http://dx.doi.org/10.1038/35002501
Neckel-Olivieira, S. & C. Gascon (2006). Abundance, body size and movement
patterns of a tropical tree frog in continuous and fragmented forests in the
Brazilian Amazon. Biological Conservation 128(3): 308–315; http://dx.doi.org/10.1016/j.biocon.2005.09.037
Ninan, K.N. & J. Sathyapalan (2005). The economics of biodiversity
conservation: a study of a coffee growing region in the Western Ghats of India.Ecological Economics 55(1): 61–72; http://dx.doi.org/10.1016/j.ecolecon.2004.10.005
Noss, R.F (1990). Indicators for
monitoring biodiversity. A hierarchical approach. Conservation Biology4(4): 355–364; http://dx.doi.org/10.1111/j.1523-1739.1990.tb00309.x
Perfecto, I. (1995). Biodiversity and transformation of a
tropical agrosystem: ants in coffee plantations. Ecological Application 5: 1084–1097.
Perfecto, I., R.A. Rice, R. Greenberg
& M. van der Voort (1996). Shade coffee: a disappearing refuge for biodiversity. Bioscience 46(8): 598–608.
Perfecto, I. & J. Vandermeer(2002). Quality
of agroecological matrix in a tropical montane landscape: ants in coffee plantations in southern
Mexico. Conservation Biology 16(1): 174–182; http://dx.doi.org/10.1046/j.1523-1739.2002.99536.x
Perfecto, I., M.A.T. Dietsch& J. Vandermeer (2003). Conservation of biodiversity in coffee agro ecosystems: a
tri-taxa comparison in southern Mexico. Biodiversity and Conservation12(6): 1239–1252; http://dx.doi.org/10.1023/A:1023039921916
Pineda, E. & G. Halffler(2004). Species diversity and habitat fragmentation:
frogs in tropical montane landscape in Mexico. Biological
Conservation 117(5): 499–508; http://dx.doi.org/10.1016/j.biocon.2003.08.009
Pineda, E., C. Moreno, F. Escobar &
G. Halffter (2005). Frog, bat and dung beetle diversity in
cloud forest and coffee agro systems in Veracruz, Mexico. Conservation Biology 19(2):
400–410; http://dx.doi.org/10.1111/j.1523-1739.2005.00531.x
Pogorzeiska, H., J. Knapowski& M. Kontek (1982). Effects of certain
pesticides on sodium transport in the epithelium of isolated frog skin. Acta Physiologica 33: 189–97.
Rappole, J.H., D.I. King & J.H.V. Rivera
(2003). Coffee and conservation. Conservation
Biology 17: 334–336.
Rice, R.A. & R. Greenberg (2000). Cacao cultivation and
the conservation of biological diversity. Ambio29(3): 167–173; http://dx.doi.org/10.1579/0044-7447-29.3.167
Rödel, M.O. & R.
Ernst (2004).Measuring and monitoring anuran diversity in tropical forests: an evaluation of
methods with recommendation for standardization. Ecotropica 10: 1–14.
Schiesari, L., B. Grillitsch& H. Grillitsch (2007). Biogeographical biases in research and their consequences for linking amphibian
declines to pollution. Conservation Biology 21(2): 465–471;http://dx.doi.org/10.1111/j.1523-1739.2006.00616.x
SPSS.
(2009). SPSS Base 18.0 for
windows user’s guide. SPSS, Chicago IL.
Turner,
I.M. (1996). Species
loss in fragments of tropical rain forest: a review of the evidence. Journal of Applied Ecology 33: 200–209.
Viswanath, R. (2003). From groves to
temples. Down To Earth. http://www.cseindia.org/dte-supplement/forest20031231/from_groves.htm.
Downloaded on 1 August 2011.
Waltert, M., A. Mardiastuti & M. Muhlenberg (2004). Effects of land use on bird species
richness in Sulawesi, Indonesia. Conservation Biology 18(5): 1339–1346;http://dx.doi.org/10.1111/j.1523-1739.2004.00127.x
Welsh.H.H. & L.M. Ollivier (1998). Stream amphibians as indicators of
ecosystem stress: a case study from California’s redwoods. Ecological
Applications 8: 1118–1132; http://dx.doi.org/10.1890/1051-0761(1998)008[1118:SAAIOE]2.0.CO;2
Zachariah,
A., K.P. Dinesh, C. Radhakrishnan, E. Kunhikrishnan, M.J. Palot &
C.K. Vishnudas (2010). A new species of Polypedates Tschudi(Amphibia: Anura: Rhacophoridae) from southern Western Ghats, Kerala, India. Biosystematica 4: 55–59.
Zachariah,
A., K.P. Dinesh, E. Kunhikrishnan, S. Das, D.V. Raju, C. Radhakrishnan, M.J. Palot & S. Kalesh (2011). Nine new species of
frogs of the genus Raorchestes (Amphibia: Anura: Rhacophoridae) from southern Western Ghats, India. Biosystematica 5: 25–48.