Journal of Threatened Taxa | www.threatenedtaxa.org | 26 April 2018 | 10(5): 11551–11565

Butterfly diversity in human-modified ecosystems of southern Sikkim, the eastern Himalaya, India

Prem Kumar Chettri ¹, Kishor Sharma ², Sailendra Dewan ³ & Bhoj Kumar Acharya ⁴

^1,2,3,4 Department of Zoology, School of Life Sciences, Sikkim University, Tadong, Gangtok, Sikkim 737102, India

¹ Present address: Forest, Environment and Wildlife Management Department, Government of Sikkim, Deorali, Sikkim 737102, India

¹ chettriprem22@gmail.com, ² kisarma@gmail.com, ³ dewansailendra1992@gmail.com, ⁴ bkacharya@cus.ac.in (corresponding author)

Abstract: Understanding wild biodiversity of agroecosystems and other human dominated landscapes are crucial for the management and conservation of biological resources. Here, we studied the diversity, abundance, similarity and functionality of butterflies in different human modified ecosystems in southern Sikkim, the Eastern Himalaya. The study was conducted from January 2015 to May 2015 by covering three habitat types namely, farm-based agroforestry, large cardamom-based agroforestry and adjacent natural forest ecosystem. We followed point count method along the transect to collect data on butterflies in the study area. A total of 911 individual butterflies representing six families and 44 species were recorded during the present study in southern Sikkim. Species richness and abundances of butterflies were significantly different among the systems. While diversity and abundance were higher in forest patches, each system harbored unique species assemblages with low similarity between habitats. The information on larval host plants were available for 41 butterfly species which depended on 128 plant species belonging to 27 families. The butterfly community was dominated by oligophagous II (19 species) followed by polyphagous (11 species), monophagous (8 species) and oligophagous I (3 species). Similarly, generalist feeders had higher species and abundance compared to specialist feeders. Specialist species were confined to forest habitat, whereas generalist species were mostly restricted to cultivated systems. The findings of the study highlighted the need for conservation of traditionally managed agroecosystems in order to conserve butterflies and other associated biodiversity.

Keywords: Agroecosystems, butterfly, conservation, eastern Himalaya; host plants.

doi: http://doi.org/10.11609/jott.3641.10.5.11551-11565| ZooBank: urn:lsid:zoobank.org:pub:3C98090F-8CB7-40D4-9592-A37C23BA1E37

Editor: Sanjay Sondhi, Titli Trust, Dehradun, India. Date of publication: 26 April 2018 (online & print)

Manuscript details: Ms # 3641 | Received 08 July 2017 | Final received 23 March 2018 | Finally accepted 04 April 2018

Citation: Chettri, P.K., K. Sharma, S. Dewan & B.K. Acharya (2018). Butterfly diversity in human-modified ecosystems of southern Sikkim, the eastern Himalaya, India. Journal of Threatened Taxa 10(5): 11551–11565; http://doi.org/10.11609/jott.3641.10.5.11551-11565

Copyright: © Chettri et al. 2018. Creative Commons Attribution 4.0 International 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: This manuscript is an outcome of the M.Sc. dissertation of the first author.

Competing interests: The authors declare no competing interests.

Author Details: Prem Kumar Chettri holds MSc (Zoology) from Sikkim University and currently works at the Forest, Environment and Wildlife Management Department, Government of Sikkim. He has a keen interest on biodiversity of Sikkim Himalaya with special focus on butterflies and plants. Kishor Sharma is a PhD scholar at the Department of Zoology, Sikkim University. His research interests are to understand the diversity and distribution patterns of birds and butterflies in the agroecosystem-forest gradient of Sikkim Himalaya. Sailendra Dewan is a PhD scholar at the Department of Zoology, Sikkim University. His research focuses on distribution pattern and phylogeny of butterflies along elevation gradients in the Sikkim Himalaya. Bhoj Kumar Acharya is a faculty in the Department of Zoology, Sikkim University, Gangtok. His research interests are to understand the large-scale ecological patterns with particular emphasis on species richness, abundance and distribution patterns along ecological gradients in the Himalaya.

Author Contribution: Study designed by BKA, PKC, KS; data collected by PKC, KS; analyzed the data by KS, PKC, SD, BKA and PKC, KS, SD, BKA wrote the manuscript.

Acknowledgements: We thank Vice Chancellor, Sikkim University, Dean, School of Life Sciences and Head, Department of Zoology, Sikkim University for facilities to undertake this research, and faculty members of Zoology Department, Sikkim University for cooperation and insightful discussion. We also thank PCCF cum Secretary, Chief Wildlife Warden and Principal Research Officer, Forests, Environment and Wildlife Management Department, Government of Sikkim for granting permission to carry out the study. Support received from local communities of Ralong Village is highly appreciated.

INTRODUCTION

Increased rates of deforestation and forest degradation over the past century have resulted in significant biological attrition globally (Barlow et al. 2007; Primack 2014). Due to ever-increasing human population and subsequent conversion of primary forests for agricultural expansion, many species have lost their potential habitat leading to local extirpation. For example, a large percentage of red-listed species has been threatened by agricultural intensification (Norris 2008). The increasing pressures on the environment by humans necessitate preservation of natural areas crucial for the persistence of biological diversity.

There is a growing concern that, loss of biodiversity will result in declining ecosystem services (Kunte 2000; Kremen et al. 2002; Hooper et al. 2005; Tscharntke et al. 2005). In agroecosystems, natural biodiversity provides a variety of ecosystem services such as pollination, recycling of nutrients, regulation of microclimate and local hydrological processes, suppression of pests and detoxification of noxious chemicals, securing crop protection and soil fertility, etc. (Altieri 1999; Lal 2004; Montagnini & Nair 2004). Most species, which primarily inhabit forests, also interact with agroecosystems and a large proportion of the total species of the region are likely to be encountered in agroecosystems (Pimentel et al. 1992). The management of these agricultural systems can dramatically affect overall levels of biodiversity, as well as the sustenance of particular species. Additionally, understanding biodiversity of agroecosystems and other human dominated landscapes is crucial for the management and conservation of biological resources. In the eastern Himalaya, it has been suggested to formulate planning for land use based on butterfly-forest type associations, by considering forest sub-types as units of conservation (Singh 2017).

Butterfly has been used as an indicator taxa to assess the health of different land use systems (Schulze et al. 2004b). Many studies have recorded higher diversity of butterflies in agroecosystems, e.g. in USA (Meehan et al. 2012), Vietnam (Lien & Yuan 2003), Costa Rica (Horner-Devine et al. 2003) and Japan (Kitahara 2004; Kitahara et al. 2008). Butterfly community is significantly affected by habitat loss and modification, and anthropogenic disturbances (Perfecto et al. 2003; Bobo et al. 2006; Posa & Sodhi 2006). In central Sulawesi, Schulze et al. (2004a) found a steady decline in butterfly species diversity from natural forest, to old secondary forest, secondary forests, agroforestry systems and maize field sites but no significant difference between natural and old secondary forests sites. In Cameroon, however, Bobo et al. (2006) reported a significant decline of butterfly richness and abundance from secondary forests and agroforestry sites towards near primary forests and annual crop sites and high species turn over along the gradient of land conversion but with loss of range-restricted and forest species. The studies in tropical regions have reported decline in butterfly species richness with increasing management intensity (Mas & Dietsch 2003; Francesconi et al. 2013). Schulze et al. (2010) highlighted the importance of human-modified habitats for conservation of overall biodiversity across all major tropical regions. Along a gradient from open to forest habitats, species’ habitat preferences significantly relates to population trends; drastic decline of open-habitat species and moderate increase of forest species (Herrando et al. 2016). Endemicity and larval host plant specificity have been reported as significant predictors of vulnerability to habitat disturbance for butterflies (Posa & Sodhi 2006).

Studies on butterfly communities in India have focused mostly on protected areas or forest ecosystems (Uniyal & Mathur 1998; Uniyal 2004, 2007; Barua 2007; Barua et al. 2010; Singh 2010, 2017; Sengupta & Ghorai 2013; Sethy et al. 2014; Acharya & Vijayan 2015; Chettri 2015; Sondhi & Kunte 2016). A few ecological studies have reported the butterfly communities in agroecosystems in India, mostly from the Western Ghats region (Kunte 1997; Kunte et al. 1999; Shahabuddin & Ali 2001; Dolia et al. 2008; Mone et al. 2014). The natural vegetation types harbor greater diversity than human-modified habitats but home gardens and agricultural fields display distinct species composition (Kunte et al. 1999). Distance to protected area and percentage canopy cover influenced abundance and richness of butterflies in the Western Ghats (Dolia et al. 2008). High butterfly diversity including legally protected species has been reported in agri-horticultural ecosystems (Das et al. 2016) and also in tea and coffee plantations (Bora & Meitei 2014; Mone et al. 2014).

Generally, the efforts to preserve biodiversity have focused on establishment of protected area network (PAN) that constitute about 13% of terrestrial lands globally and amounts to one-third of the agricultural lands (38% land cover globally) (Venter et al. 2014; World Bank 2017). Protected areas around the world not only conserve and safeguard biodiversity but also provide essential benefit to local people such as protecting water supplies, food, medicines as well as traditional values, landscape and sustenance for livelihoods. But the establishment of protected area in human-modified landscape is not feasible which necessitates the preservation of existing wild biodiversity in the agricultural systems and surrounding forest patches with the involvement of local communities. The PAN in the Himalayan region is mostly confined to the high elevation areas and there is poor coverage of PAN at low to mid elevations although these areas are rich in biodiversity (Chettri et al. 2008; Shrestha et al. 2010; Acharya et al. 2011; Bhardwaj et al. 2012; Acharya & Sharma 2013). The low to mid elevation areas are represented by mosaic landscape of cultivated systems and forests. The management of these cultivated systems in Sikkim are both traditional (Sharma 2009; Sharma & Acharya 2013) and organic (Bhutia 2015).

The previous studies on butterflies of Sikkim have been conducted in PAN or forest ecosystems (Haribal 1992; Acharya & Vijayan 2015; Chettri 2015). Rai et al. (2012), however, reported the rediscovery of two very rare species protected under Schedule I of Indian Wildlife (Protection) Act 1972 from human-modified ecosystems of Sikkim. PAN coverage in Sikkim is almost 31 % of the total geographical area of the state comprising one national park and seven wildlife sanctuaries. With the exception of Kitam Bird Sanctuary (geographical area of 6km²), there is no PAN coverage below 1,500m in the state. Occurrence of high species richness, narrow elevation range of most species and absence of PAs at low to mid-elevation has pointed a way for extension of conservation efforts to these elevation sites (Acharya & Vijayan 2015). Since the areas below 2,000m are almost entirely inhabited by people and the major chunk of forests fall under private holdings, conservation can be achieved only through the involvement of the local community as suggested for mountainous areas (Kollmair et al. 2005). Hence, the present study was undertaken to understand the biodiversity conservation value of agroecosystems in Sikkim by assessing the butterfly diversity in three representative human-modified ecosystems: farm-based agroforestry systems and large cardamom-based agroforestry system along with adjoining natural forest in southern Sikkim, the eastern Himalaya, India.

MATERIALS AND METHODS

Study area

The study was conducted at Ralong Village (27.31⁰N & 88.33⁰E) in southern Sikkim located in the eastern Himalaya, India (Fig. 1; Table 1). The village is situated between 1,800m and 2,100m elevation with a total geographical area of around 5km². The region has a cool temperate type of climate with a maximum temperature of 17–27⁰C, minimum temperature of 02–21⁰C and mean annual rainfall of 162cm. Sikkim is a part of the eastern Himalaya, which fall under one among the 35 global biodiversity hotspots (Conservation International 2017). Despite its small geographical area (7,096km²), Sikkim is one of the richest Indian states in terms of biodiversity harboring around 43% mammals, 45% birds, 50% butterflies and 11% flowering plants of the Indian subcontinent (Acharya & Sharma 2013). The total forest cover of Sikkim is 3,389km², which accounts for 47.46% of the total geographical area of the state.

We selected three representative ecosystem types for the present study (Table 1) which are described below:

Table 1. Details of transects established for sampling butterflies in farm-based agroforestry system (FAS), large cardamom-based agroforestry system (LCAS) and natural forest system (NFS) of Ralong, southern Sikkim, eastern Himalaya.

Habitat type	Farm-based agroforestry system	Large cardamom-based agroforesary system	Natural forest system
Dominant vegetation	Schima wallichii, Alnus nepalensis, Albizia spp., Terminalia myriocarpa, Acer campbelli, Castanopsis hystrix	Alnus nepalensis, Albizia spp., Terminalia myriocarpa, Acer campbelli, Castanopsis hystrix	Michelia spp., Pteris villosa, Quercus lamellosa, Rhus insignis, Quercus thomsonii, Quercus spicata, Symplocos theifolia.
Elevation (m)	1700–1900	1700–2100	1700–2100
Latitude	27.3449^0N	27.3315^0N	27.3348^0N
Longitude	88.3405^0E	88.3366^0E	88.3372^0E
Sampling effort (No. of points covered)	90	90	90
Time devoted for sampling (in days)	9	9	9

Farm-Based Agroforestry System (FAS)

Farm based agroforesty system is important land use practice in hilly terrains. It is primarily an agri-silvicultural system comprising home gardens and livestock rearing (Sharma 2009). A variety of crops such as maize, potato, millet, beans, pulses, peas and cabbage are cultivated in this system. Dominant tree species that occur in the system are Schima wallichii, Alnus nepalensis, Albizia spp., Terminalia myriocarpa, Acer campbelli, Castanopsis hystrix, etc.

Large Cardamom-based Agroforestry System (LCAS)

Large cardamom-based agroforestry is a traditional farming system basically practiced in mountain areas especially in Nepal, Bhutan, Sikkim and Darjeeling. Large cardamom is an important cash crop grown as an understory perennial crop predominantly under the shade of Himalayan alder Alnus nepalensis (Sharma 2009; Sharma et al. 2016). Other shade tree species such as Albizia spp., Terminalia myriocarpa, Acer campbelli, Castanopsis spp., Echinocarpus dasycarpus, Eurya acuminata, Juglans regia, Quercus lamellosa, Quercus spicata, Rhus insignis, Symplocos theifolia, Viburnum cordifolium, Zanthoxylum sp. etc also occur in this system.

Natural Forest Systems (NFS)

The cultivated systems are encircled by small patches of natural forests where the local community depends on fuel wood and cattle fodder. The main type of vegetation in Ralong is temperate broad-leaved forests which comprises tree species such as Michelia spp., Pteris villosa, Quercus lamellosa, Rhus insignis, Quercus thomsonii, Quercus spicata, Symplocos theifolia, Zanthoxylum sp., Echinocarpus dasycarpus, Elaeocarpus sikkimensis, Albizia procera, Beilschmiedia roxburghiana, Eurya acuminata, Ficus hookeri, etc.

Study design and sampling

The study was designed to cover three representative ecosystem types available in the present study area (FAS, LCAS and NFS). Depending upon the availability of suitable plots and accessibility, we established transect each of 1km length in all the three study systems (Table 1; Fig. 1). Along the transects permanent points were established which were spaced 100m apart making 10 points per transect. We covered equal area (approximately one hectare) in all the three ecosystem types.

We followed point count methods along the transect for sampling butterflies in the study area following Pollard (1977) and Acharya & Vijayan (2015). We conducted five minutes count within 5m radius in each point recording the identity and abundances of butterflies. The sampling of butterflies was done by uniformly covering all the points from January to May 2015. Sampling was done on clear sunny days in the morning from 10:00 hrs to 13:00 hrs when the activity of butterflies remains at its highest. The butterflies were identified at the wing based on photographic plates given in Haribal (1992), Kehimkar (2008) and Sondhi et al. (2013). In cases where instant identification was not possible, photographs were taken and identified using various resources including ifoundbutterflies.org (Kunte et al. 2017). We completed a total of 27 transect visit (nine in each of the study system) totaling 270 point counts. No collection of butterfly specimens was done during this study in Sikkim.

Data Analysis

Community parameters such as species richness, abundance, Shannon-Weiner diversity index and evenness were calculated for total samples as well as each habitat type following Magurran & McGill (2011). Species richness was considered as the total number of species observed and species abundance as number of individual butterflies counted during the sampling. The diversity was analyzed using Shannon-Wiener diversity index (H′) = – Σ pilnpi; where pi = proportion of total sample belonging to i^th species, ln= natural logarithm (Shannon & Weaver 1949). Similarly, evenness was calculated using the formula: Evenness (J) = H′/H_max where H_max= lnS, S = number of species, H′ = Shannon–Wiener Diversity (Pielou 1969). Based on the observation, we also estimated non-parametric species richness estimators using the software EstimateS version 9.1.0 (Colwell 2013). Using the various estimators and observed richness, species accumulation curves were generated for all the three systems. Among the non-parametric estimators Chao1, Jackknife 1 and Jackknife 2 were preferred because the data was represented by many rare species (singletons and doubletons); these estimators are less sensitive to the patchiness of the species distribution and variability in the probability of encountering species (Colwell & Coddington 1994). To understand the species similarity among the systems, Morisita-Horn similarity index were calculated using EstimateS version 9.1.0 (Colwell 2013).

Variation in species richness and abundances of butterflies among systems was tested using one way ANOVA. Pair wise multiple comparisons based on Tukey’s HSD was also conducted to assess the significant difference in the species and abundance of butterflies per point among the three systems. In order to understand the species-abundance pattern of butterfly community, we tested the four distribution model (geometric, log series, truncated log-normal and MacArthur’s broken stick) to describe the species–abundance distribution pattern of ecological community (see Magurran & McGill 2011).

We computed relative percentages of butterflies (both species richness and abundance) in each category (butterfly family, habitat specialization and larval host plant specificity). We also assessed the number of larval host plants (family and species) for all the six butterfly family, and butterfly species: host plant species ratio.

Information on habitat specialization for each of the species observed in the study area was obtained from Wynter-Blyth (1957), Haribal (1992), Kunte (2000) and Kehimkar (2008). Each butterfly species was then classified into five habitat specialization classes (Forest interior only, Forest interior + Forest edge, Forest edge only, Openland+forest edge and Openland only) following Kitahara (2004).

Information on larval host plant for each of the species observed in the present study was obtained from different standard references (Haribal 1992; Kunte 2000; Kehimkar 2008; Tiple 2012; Sengupta et al. 2014; Kunte et al. 2017) and field observations. The larval host specificity of butterfly community was assessed by classifying them into monophagous (one species of larval host plant), oligophagous I (>1 species of larval host plant within only one genus in a family), oligophagous II (larval host plant in >1 genus but within a single family) and polyphagous (multiple species of larval host plant in several plant families) following standard methods (Steffan-Dewenter & Tscharntke 1997; Kitahara 2004; Kitahara et al. 2008).

RESULTS

Species richness, diversity and abundance

We observed 911 individual butterflies representing 44 species and six families during this study in southern Sikkim. Species richness, abundance, diversity and evenness of butterflies differed among the three systems (Table 2). Species richness was highest in NFS (32 species, 72.7%), followed by FAS (24 species, 54.5%) and least in LCAS (20 species, 45.5%). Out of the total abundance of butterflies, about 52% were observed in FAS and the rest (48%) in other two systems. But species per point was significantly higher in the FAS compared to other two systems (One way ANOVA: F _{2, 267} = 65.432; P≤0.01) (Table 2; Fig. 2a). Similarly, there was a significant variation in abundance per point of butterflies among the three systems (One way ANOVA: F_{2, 267} = 85.917; P≤0.01) with highest value in FAS (5.2±2.0) and the lowest in LCAS (Table 2; Fig. 2b). The pair-wise multiple comparisons based on Tukey’s HSD test showed significant difference in species per point and abundance per point among all the system pairs (Table 3). Both evenness and Shannon-Weiner diversity index was highest in the forest system compared to other systems (Table 2).

The species accumulation curve almost approached an asymptote in FAS and LCAs but still rising in NFS indicating likelihood of detection of additional species from the study area (Fig. 3). It indicates that there was a probability of encountering few additional species in NFS with the increasing sampling effort.

Family wise distribution

The observed butterflies belonged to six families namely, Hesperiidae, Papilionidae, Lycaenidae, Riodinidae, Pieridae and Nymphalidae. The butterfly families differed among the three systems both in terms of species richness and abundance (Fig. 4). Butterflies belonging to all the six families were observed in LCAS and NFS but species from Hesperiidae and Papilionidae families were absent in FAS. In terms of relative species richness, Nymphalidae was the most dominant family in FAS (50%) with twelve species, followed by Lycaenidae (29.2%) with seven species, Pieridae (16.7%) with four species and Riodinidae (4.2%) with one species. Similarly, Nymphalidae (45%) with nine species, Lycaenidae (25%) with five species, Pieridae (15%) with three species and Papilionidae, Hesperiidae and Riodinidae (5% each) with one species each were observed in LCAS. In the NFS, Nymphalidae (53.1%) with 17 species, Lycaenidae (15.6%) with five species, Pieridae (12.5%) with four species, Riodinidae (9.4%) with three species and Papilionidae (3.1%) with one species and Hesperiidae (6.3%) with two species were observed. In terms of relative abundance (%), however, the most abundant family in all the three systems (FAS, LCAS, NFS) was Pieridae (42.4%, 44.1%, 41.9%), followed by Nymphalidae (35.9%, 26.8%, 29.1%) and Lycaenidae (21.5%, 26.8%, 19.4%). Abundance of Riodinidae was highest in NFS (7.8%) which declined in FAS (0.2%) and LCAS (0.6%).

Species similarity and community structure

Among the 44 species, eight species (18.2%) were common to all the three habitats, whereas 20 species (45.5%) were exclusively observed in a single habitat (10 in NFS, five each in FAS and LCAS) (Table 2). FAS shared 17 species with NFS and 10 species with LCAS. LCAS shared 13 species with NFS. Based on the pair-wise Morisita-Horn similarity index value it is observed that all three systems harbored unique assemblages of species with low similarity between sites (Table 4).

Abundance pattern

Out of the total 911 individuals butterflies, Indian Cabbage White was the most abundant species and constituted 32.5% of the total butterflies followed by Metallic Cerulean (16.8 %) and Indian Tortoiseshell (10.6%).

Among the four models of species-abundance distribution pattern, data on butterflies of the present study showed best fit to truncated log normal model as there was no significant difference between observed and expected number of species in each abundance class (χ²= 3.61; p = 0.60; df = 5). The abundance distribution pattern showed that community is dominated by a few abundant and many rare species (Fig. 5).

Table 2. Species richness, abundance, diversity and evenness of butterfly observed in farm-based agroforestry system (FAS), large cardamom-based agroforestry system (LCAS) and natural forest system (NFS) of Ralong, southern Sikkim, eastern Himalaya.

Parameters	FAS	LCAS	NFS	Total
Species richness	24	20	32	44
Abundance	474	179	258	911
Species per point (Mean± SD)	3.2±1.0	1.4±1.1	2.3±0.9	2.3±1.2
Abundance per point (Mean± SD)	5.2±2.0	2.0±1.7	2.7±1.4	3.3±2.2
Diversity (H’)	2.18	2.07	2.59	2.4
Evenness (J)	0.67	0.69	0.74	0.70
Habitat exclusive species	5	5	10	20

Table 3. ANOVA and multiple comparison based on Tukey’s HSD for species per point and abundance per point of butterfly community among farm-based agroforestry system (FAS), large cardamom-based agroforestry system (LCAS) and natural forest system (NFS) of Ralong, southern Sikkim, eastern Himalaya. **: significant at p≤0.01.

	F2, 267	P	Multiple comparisons	Mean difference	P
Species per point	65.432	0.000**	FAS vs LCAS	1.744	0.000**
			FAS vs NFS	0.911	0.000**
			LCAS vs NFS	-0.833	0.000**
Abundance per point	85.917	0.000**	FAS vs LCAS	3.256	0.000**
			FAS vs NFS	2.522	0.000**
			LCAS vs NFS	-0.733	0.000**

Table 4. Species similarity of butterflies between three systems at Ralong, southern Sikkim, eastern Himalaya. The figures below diagonal represent the pair-wise Morisita-Horn species similarity index and corresponding value above diagonal represents the total species shared by the two systems. FAS - farm-based agroforestry system; LCAS - large cardamom-based agroforestry system; NFS - natural forest system.

Habitats	FAS	LCAS	NFS
FAS	-	10	17
LCAS	0.49	-	13
NFS	0.642	0.362	-

Habitat specialization

Butterflies under different habitat specialization classes showed distinct pattern in the three ecosystems (Fig. 6). As expected, forest interior species, both in terms of species richness (4.2-25%) and abundance (0.4-12.0%), were highest in NFS which declined slightly in LCAS but sharply in FAS. Forest interior + forest edge species were absent in FAS and LCAS and recorded only in NFS with low species richness (1.2%) and abundance (6.3%).

The species richness of forest edge only species were highest in NFS which declined by about 25% in LCAS and 50% in FAS. Similarly, their abundance was also highest in NFS which declined by about 50% in LCAS and four times in FAS. Species richness of openland + forest edge species declined from FAS towards NFS through LCAS and their relative abundance was highest in FAS and least in LCAS. Species richness of open land only was least in NFS and increased about four and five times, respectively in LCAS and FAS. Their abundances were also least in NFS which increased around two times in FAS and LCAS.

Larval host plant specificity

Out of 44 species observed in the present study, information on larval host plant could be obtained only for 41 species representing 897 individuals. These 41 species depended on 128 plant species (belonging to 27 families) as larval host plant (Appendix I; Table 5). The butterfly community was dominated by oligophagous II (19 species; 46.3%) followed by polyphagous (11 species; 26.8%) and monophagous (8 species; 19.5%) and least for oligophagous I (3 species; 7.3%) (Figure 7). In terms of abundance oligophagous II (57.9%) showed the highest value followed by polyphagous (25.2%), oligophagous I (12.5%) and minimum for monophagous (4.55%).

Butterflies considered as generalist feeder (Polyphagous + Oligophagous II) showed high richness (30 species; 73.2%) compared to specialist feeder (monophagous + oligophagous I) (11 species; 26.8%). Similar trend was observed in terms of butterfly populations. Monophagous and oligopahgous species were restricted to NFS, whereas oligophagous II and polyphagous were mostly confined to cultivated systems (Fig. 7).

Table 5. Analysis of the larval host plants of the butterflies observed in Ralong, southern Sikkim, eastern Himalaya

Butterfly family	Butterfly species	Host plant family	Host plant species	Ratio (butterfly species: host plant species)
Hesperiidae	2	2	3	0.67
Lycaenidae	6	6	19	0.32
Nymphalidae	25	20	75	0.33
Papiliondae	1	1	4	0.25
Pieridae	4	4	22	0.18
Riodinidae	3	1	3	1.00
Total	41*	27	128	0.32

*Data for larval host plant were not available for three species (two for Lycaenidae and one for Nymphalidae family)

DISCUSSION

During this study a total of 44 species belonging to six families of butterflies were recorded from three ecosystems in southern Sikkim, the eastern Himalaya. These species comprise 6.38% species of the butterflies reported from Sikkim (Haribal 1992). The total species observed during this study was low which may be because of number of reasons, e.g., the study was conducted in a small geographical area and for a short time span (five months; winter and pre-monsoon season) and did not cover the monsoon and post monsoon seasons when the butterflies are most abundant in India (Kunte et al. 1999; Acharya & Vijayan 2015; Chettri 2015). Nonetheless, this study explored the potentiality of cultivated systems in harboring butterflies in an important part of global biodiversity hotspot of the Himalaya.

Species richness and diversity of butterfly were high in the forest system as compared to other systems. It is expected because forests system comprised undisturbed patch of vegetation with tall trees and abundant flowering plants which provide favorable habitat to the butterflies. Butterfly community is significantly affected by habitat loss and modification (Perfecto et al. 2003; Bobo et al. 2006; Chettri 2010). Land use change and agricultural intensification leads to homogenization of butterfly community (Ekroos et al. 2010) with species assemblage shifting from specialist to generalist (Börschig et al. 2013). Some studies reported poor representation of butterflies in farmland habitats (Schulze et al. 2004b; Fitzherbert et al. 2006; Vu 2009); however, many studies have found higher diversity of butterflies in agro-ecosystems (Horner-Devine et al. 2003; Lien & Yuan 2003; Bobo et al. 2006; Dolia et al. 2008; Kitahara et al. 2008).

Nymphalidae was the most dominant family in terms of species richness. Similar pattern of dominance of Nymphalidae in the butterfly communities have been reported in other studies conducted in forests and human-modified ecosystems (Uniyal 2007; Vu 2013; Acharya & Vijayan, 2015; Chettri 2015; Nandakumar et al. 2015; Das et al. 2016; Singh 2017).

The butterfly communities in all the three habitats showed distinct species assemblage with very low similarity and high turnover rate between them. It indicates the importance of cultivated systems in conservation of unique butterfly assemblages. The low similarity among systems reflect the uniqueness of each habitat in terms of quality, resource availability and their distribution pattern specific to the preference of butterflies (Blair & Launer 1997).

Species abundance distribution pattern of butterfly fitted to truncated lognormal distribution showing no significant difference in observed and expected number of species in each abundance classes. This is an indication of the rather stabilized ecological community (Magurran & McGill 2011).

Forest habitat harbored large number of specialist species (monophagous and forest interior), whereas cultivated systems mostly harbored open habitat and generalist species (open land and polyphagous). Similar trend was reported in the Himalaya (Bhardwaj et al. 2012), Western Ghats (Kunte et al. 1999; Dolia et al. 2008) and elsewhere (Francesconi et al. 2013; Herrando et al. 2016). Specialist and rare species are mostly encountered in forests and metric decreases with increasing forest habitat disturbance levels (Mayfield et al. 2005; Vu 2013). Conversely, common species increase with growing forest habitat disturbance levels. Butterfly community is mostly determined by the larval host plants (Kitahara 2004; Barua 2007; Kitahara et al. 2008; Sengupta et al. 2014), nectar plants (Barua 2007; Sengupta & Ghorai 2013), plant species richness, herb and shrub density (Bhardwaj et al. 2012), tree species richness and density (Chettri 2010; Acharya & Vijayan 2015). Habitat specialist species confined to NFS were mostly from Papilionidae and Hesperiidae families. Papilionids have been reported as very sensitive to loss of primary forest habitat and land use change (Barua et al. 2010).

CONCLUSION

This short-term study on butterflies of Ralong, southern Sikkim indicated the significance of cultivated systems and human influenced landscapes for conservation of butterflies and other biodiversity elements. Most of the studies on biodiversity are focused on forests, and areas outside the protected areas are not given due importance from the conservation point of view. This study reflects that although the forest is richer in terms of species, there are many species which occur only in the cultivated systems. Hence, for the conservation of these species cultivated systems should be given due consideration in conservation programs. Original remnant patches of forest and native vegetation among agricultural fields can be retained in consultation with various stakeholders and local communities and managed without further loss of biodiversity. Further studies designed to assess diverse taxa sampled across all the four seasons (winter, pre-monsoon, monsoon and post monsoon) in a long term basis undertaking large geographical area, large elevation range, diverse ecosystems covering the larval and adult stage would provide better insights on the importance of cultivated systems in conservation of biodiversity.

REFERENCES

Acharya, B.K., N. Sanders, L. Vijayan & B. Chettri (2011). Elevational gradients in bird diversity in the eastern Himalaya: an evaluation of distribution patterns and their underlying mechanisms. PLoS ONE 6:e29097; http://doi.org/10.1371/journal.pone.0029097

Acharya, B.K. & G. Sharma (2013). Forests and biodiversity in Sikkim, pp. 42–70. In: Kharel, S. & J. Bhutia (eds.). Gazetteer of Sikkim. Home Department, Government of Sikkim, Gangtok.

Acharya, B.K. & L. Vijayan (2015). Butterfly diversity along the elevation gradient of eastern Himalaya, India. Ecological Research 30(5): 909–919; http://doi.org/10.1007/s11284-015-1292-0

Altieri, M.A. (1999). The ecological role of biodiversity in agroecosystems. Agriculture, Ecosystems & Environment 74(1): 19–31; http://doi.org/10.1016/S0167-8809(99)00028-6

Barlow, J., T.A. Gardner, I.S. Araujo, T.C. Ávila-Pires, A.B. Bonaldo, J.E. Costa, M.C. Esposito, L.V. Ferreira, J. Hawes, M.I.M. Hernandez, M.S. Hoogmoed, R.N. Leite, N.F. Lo-Man-Hung, J.R. Malcolm, M.B. Martins, L.A.M. Mestre, R. Miranda-Santos, A.L. Nunes-Gutjahr, W.L. Overal, L. Parry, S.L. Peters, M.A. Ribeiro-Junior, M.N.F. da Silva, C. da Silva Motta & C.A. Peres (2007). Quantifying the biodiversity value of tropical primary, secondary, and plantation forests. Proceedings of the National Academy of Sciences 104(47): 18555–18560; http://doi.org/10.1073/pnas.0703333104

Barua, K.K. (2007). Diversity and habitat selection of Papilionidae in a protected forest reserve in Assam, Northeast India. Doctoral thesis. University of Gottingen, Gottingen, Germany, 273pp.

Barua, K.K., J. Slowik, K.S. Bobo & M. Muehlenberg (2010). Correlations of rainfall and forest type with papilionid assemblages in Assam in northeast India. Psyche 2010: 1–10; http://doi.org/10.1155/2010/560396

Bhardwaj, M., V.P. Uniyal, A.K. Sanyal & A.P Singh (2012). Butterfly communities along an elevational gradient in the Tons valley, Western Himalayas: Implications of rapid assessment for insect conservation. Journal of Asia-Pacific Entomology 15(2): 207–217; http://doi.org/10.1016/j.aspen.2011.12.003

Bhutia, D.T. (2015). Sikkim Organic Mission “Journey of a fully organic state”. Department of Food Security & Agriculture Development and Horticulture and Cash Crops Development, Government of Sikkim, 287pp.

Blair, R.B. & A.E. Launer (1997). Butterfly diversity and human land use: species assemblages along an urban gradient. Biological Conservation 80(1): 113–125; http://doi.org/10.1016/S0006-3207(96)00056-0

Bobo, K.S., M.Waltert, H. Fermon, J. Njokagbor & M. Mühlenberg (2006). From forest to farmland: Butterfly diversity and habitat associations along a gradient of forest conversion in Southwestern Cameroon. Journal of Insect Conservation 10(1): 29–42; http://doi.org/10.1007/s10841-005-8564-x

Bora, A. & L.R. Meitei (2014). Butterfly fauna (Order: Lepidoptera) in five major tea gardens of Sivasagar District, Assam, India. Biological Forum - An International Journal 6(2): 7–15.

Börschig, C., A.M Klein, H. von Wehrden & J. Krauss (2013). Traits of butterfly communities change from specialist to generalist characteristics with increasing land-use intensity. Basic and Applied Ecology 14(7): 547–554; http://doi.org/10.1016/j.baae.2013.09.002

Chettri, N. (2010). Cross-taxon congruence in a trekking corridor of Sikkim Himalaya: Surrogate analysis for conservation planning. Journal for Nature Conservation 18: 75–88; http://doi.org/10.1016/j.jnc.2009.03.003

Chettri, N. (2015). Distribution of butterflies along a trekking corridor in the Khangchendzonga Biosphere Reserve, Sikkim, Eastern Himalayas. Conservation Science 3(1): 1–10; http://doi.org/10.3126/cs.v3i1.13767

Chettri, N., B. Shakya, R. Thapa & E. Sharma (2008). Status of a protected area system in the Hindu Kush-Himalayas: An analysis of PA coverage. The International Journal of Biodiversity Science and Management 4(3): 164–178; http://doi.org/10.3843/Biodiv.4.3:4

Colwell, R.K. (2013). EstimateS: Statistical estimation of species richness and shared species from sample (Version 9.1.0). User guide and application available at http://viceroy.eeb.uconn.edu/estimates/

Colwell, R.K. & J.A. Coddington (1994). Estimating terrestrial biodiversity through extrapolation. Philosophical transactions of Royal Society London B: Biological Sciences 345: 101–118.

Conservation International (2017). Hotspots. Targeted investment in nature’s most important places. Conservation International. Downloaded from http://www.conservation.org Accessed on 15 September 2017.

Das, M., H. Mishra & J. Saikia (2016). Diversity and species richness of butterfly in an Agri-Horti habitat in Assam, India. The Bioscan 11(2): 801–805.

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 11(1): 26–34; http://doi.org/10.1111/j.1469-1795.2007.00143.x

Ekroos, J., J. Heliölä & M. Kuussaari (2010). Homogenization of Lepidopteran communities in intensively cultivated agricultural landscapes. Journal of Applied Ecology 47(2): 459–467; http://doi.org/10.1111/j.1365-2664.2009.01767.x

Fitzherbert, E., T. Gardner, T.R.B. Davenport & T. Caro (2006). Butterfly species richness and abundance in the Katavi ecosystem of western Tanzania. African Journal of Ecology 44(3): 353–362; http://doi.org/10.1111/j.1365-2028.2006.00655.x

Francesconi, W., P.K.R. Nair, D.J. Levey, J. Daniels & L. Cullen (2013). Butterfly distribution in fragmented landscapes containing agroforestry practices in Southeastern Brazil. Agroforestry Systems 87(6): 1321–1338; http://doi.org/10.1007/s10457-013-9640-y

Haribal, M. (1992). The Butterflies of Sikkim Himalaya and their natural history. Sikkim Nature Conservation Foundation, Gangtok, 217pp.

Herrando, S., L. Brotons, M. Anton, F. Páramo, D. Villero, N. Titeux, Q. Javier & C. Stefanescu (2016). Assessing impacts of land abandonment on Mediterranean biodiversity using indicators based on bird and butterfly monitoring data. Environmental Conservation 43(1): 69–78; http://doi.org/10.1016/S0167-8809(99)00028-6

Hooper, D.U., F.S. Chapin III, J.J. Ewel, A. Hector, P. Inchausti, S. Lavorel, J.H. Lawton, D.M Lodge, M. Loreau, S. Naeem, B. Schmid, H. Setälä, A.J. Symstad, J. Vandermeer & D.A. Wardle (2005). Effects of biodiversity on ecosystem functioning: A Consensus of current knowledge. Ecological Monographs 75(1): 3-35; http://doi.org/10.1890/04-0922

Horner-Devine, M.C., G.C. Daily, P.R. Ehrlich & C.L. Boggs (2003). Countryside biogeography of tropical butterflies. Conservation Biology 17(1): 168-177; http://doi.org/10.1046/j.1523-1739.2003.01310.x

Kehimkar, I. (2008). The Book of Indian Butterflies. Bombay Natural History Society, Oxford University Press, Mumbai, 497pp.

Kitahara, M. (2004). Butterfly community composition and conservation in and around a primary woodland of Mount Fuji, central Japan. Biodiversity and Conservation 13(5): 917–942; http://doi.org/10.1023/B:BIOC.0000014462.83594.58

Kitahara, M., M. Yumoto & T. Kobayashi (2008). Relationship of butterfly diversity with nectar plant species richness in and around the Aokigahara primary woodland of Mount Fuji, central Japan. Biodiversity and Conservation 17(11): 2713–2734; http://doi.org/10.1007/s10531-007-9265-4

Kollmair, M., G.S. Gurung, K. Hurni & D. Maselli (2005). Mountains: Special places to be protected? An analysis of worldwide nature conservation efforts in mountains. International Journal of Biodiversity Science and Management 1: 1–9; http://doi.org/10.1111/j.1469-1795.2007.00143.x

Kremen, C., N.M. Williams & R.W. Thorp (2002). Crop pollination from native bees at risk from agricultural intensification. Proceedings of the National Academy of Sciences 99(26): 16812–16816; http://doi.org/10.1073/pnas.262413599

Kunte, K.J. (1997). Seasonal patterns in butterfly abundance and species diversity in four tropical habitats in northern Western Ghats. Journal of Biosciences 22(5): 593–603; http://doi.org/10.1007/BF02703397

Kunte, K. (2000). Butterflies of Peninsular India. Universities Press (Hyderabad) and Indian Academy of Sciences (Bangalore), 272pp.

Kunte, K., A. Joglekar, U. Ghate & P. Pramod (1999). Patterns of butterfly, birds and tree diversity in the Western Ghats. Current Science 77(4): 577–586.

Kunte, K., S. Sondhi & P. Roy (2017). Butterflies of India, version 2.28. Indian Foundation for Butterflies, http://www.ifoundbutterflies.org/ Accessed on 5 July 2017.

Lal, R. (2004). Agricultural activities and the global carbon cycle. Nutrient Cycling in Agroecosystems 70(2): 103–116; http://doi.org/10.1023/B:FRES.0000048480.24274.0f

Lien, V.V. & D. Yuan (2003). The differences of butterfly (Lepidoptera, Papilionoidea) communities in habitats with various degrees of disturbance and altitudes in tropical forests of Vietnam. Biodiversity and Conservation 12(6): 1099–1111; http://doi.org/10.1023/A:1023038923000

Magurran, A.E. & B.J. McGill (2011). Biological Diversity: Frontiers in Measurement and Assessment. Oxford University Press, 368pp.

Mas, A.H. & T.V. Dietsch (2003). An index of management intensity for coffee agroecosystems to evaluate butterfly species richness. Ecological Applications 13(5): 1491–1501; http://doi.org/10.1890/01-5229

Mayfield, M.M., M.E. Boni, G.C. Daily & D. Ackerly (2005). Species and functional diversity of native and human-dominated plant communities. Ecology 86(9): 2365–2372; http://doi.org/10.1890/05-0141

Meehan T.D., J. Glassberg & C. Gratton (2012). Butterfly community structure and landscape composition in agricultural landscapes of the central United States. Journal of Insect Conservation 17(2): 411–419; http://doi.org/10.1007/s10841-012-9523-y

Mone, S., K.M. Kusha, D. Jathanna, M. Ali & A. Goel (2014). Comparison of insect biodiversity between organic and conventional plantations in Kodagu, Karnataka, India. Journal of Threatened Taxa 6(9): 6186–6194; http://doi.org/10.11609/JoTT.o3778.6186-94

Montagnini, F. & P.K.R. Nair (2004). Carbon sequestration: An underexploited environmental benefit of agroforestry systems. Agroforestry Systems 61(1): 281–395; http://doi.org/10.1023/B:AGFO.0000029005.92691.79

Nandakumar, M.K., V.V Sivan, J.P Joseph, M.M Jithin & M.K.R. Narayanan (2015). Butterfly species diversity and abundance in Manikkunnumala forest of Western Ghats, India. International Journal of Advanced Research 3(1): 206–211.

Norris, K. (2008). Agriculture and biodiversity conservation: opportunity knocks. Conservation Letters 1(1): 2–11; http://doi.org/10.1111/j.1755-263X.2008.00007.x

Pielou, E.C. (1969). An Introduction to Mathematical Ecology. Wiley, New York, 286pp.

Pimentel, D., U. Stachow, D.A. Takacs, H.W. Brubaker, A.R. Dumas, J.J. Meaney, J.A.S. O’Neil, D.E. Onsi & D.B. Corzilius (1992). Conserving biological diversity in agricultural/forestry systems. BioScience 42: 354–362; http://doi.org/10.2307/1311782

Posa, M.R.C. & N.S. Sodhi (2006). Effects of anthropogenic land use on forest birds and butterflies in Subic Bay, Philippines. Biological Conservation 129: 256–270; http://doi.org/10.1016/j.biocon.2005.10.041

Perfecto, I., A. Mas, T. Dietsch & J. Vandermeer (2003). Conservation of biodiversity in coffee agroecosystems: a tri-taxa comparison in southern Mexico. Biodiversity and Conservation 12: 1239–1252; http://doi.org/10.1023/A:1023039921916

Pollard, E. (1977). A method for assessing changes in the abundance of butterflies. Biological Conservation 12: 116–134; http://doi.org/10.1016/0006-3207(77)90065-9

Primack, R.B. (2014). Essentials of Conservation Biology. Sinauer Asssociates, Inc., Publishers Sunderland, Massachusetts, USA, 603pp.

Rai, S., K.D. Bhutia & K. Kunte (2012). Recent sightings of two very rare butterflies, Lethe margaritae Elwes, 1882 and Neptis nycteus de Nicéville, 1890, from Sikkim, eastern Himalaya, India. Journal of Threatened Taxa 4(14): 3319–3326; http://doi.org/10.11609/JoTT.o2965.3319-26

Schulze, C.H., I. Steffan-Dewenter & T. Tscharntke (2004a). Effects of land use on butterfly communities at the rain forest margin: A case study from Central Sulawesi, pp. 281–297. In: Gerold, G., M. Fremerey, & E. Guhardja (eds.). Land Use, Nature Conservation and the Stability of Rainforest Margins in Southeast Asia. Springer, Berlin, Heidelberg.

Schulze, C.H., M. Waltert, P.J.A. Kessler, R. Pitopang, D. Veddeler, M. Mühlenberg, S.R. Gradstein, C. Leuschner, I. Steffan-Dweneter & T. Tscharntke (2004b). Biodiversity indicator groups of tropical land-use systems: comparing plants, birds, and insects. Ecological Applications 14(5): 1321–1333; http://doi.org/10.1890/02-5409

Schulze, C.H., S. Schneeweihs & K. Fiedler (2010). The potential of land-use systems for maintaining tropical forest butterfly diversity, pp. 73–96. In: Tscharntke, T., C. Leuschner, E. Veldkamp, H. Faust, E. Guhardja, & A. Bidin (eds.). Tropical Rainforests and Agroforests under Global Change: Ecological and Socio-economic Valuations. Springer, Berlin, Heidelberg.

Sengupta, P. & N. Ghorai (2013). On the plant-butterfly interaction in the surroundings of the upper Neora Valley National Park, a sub-tropical broad leaved hill forest in the eastern Himalayan landscape of West Bengal, India. NEBIO 4(4): 21–30.

Sengupta, P., K.K. Banerjee & N. Ghorai (2014). Seasonal diversity of butterflies and their larval food plants in the surroundings of upper Neora Valley National Park, a sub-tropical broad leaved hill forest in the eastern Himalayan landscape, West Bengal, India. Journal of Threatened Taxa 6(1): 5327–5342; http://doi.org/10.11609/JoTT.o3446.5327-42

Sethy, J., S. Behera & N.S. Chauhan (2014). Species diversity of butterflies in south-eastern part of Namdapha Tiger Reserve, Arunachal Pradesh, India. Asian Journal of Conservation Biology 3(1): 75–82.

Shahabuddin, G. & R. Ali (2001). Impacts of land use change on forest butterfly communities in the Western Ghats of Southern India. Journal of Tropical Forest Science 13(3): 434–449.

Shannon, C.E. & W. Weaver (1949). The Mathematical Theory of Communication. The University of Illinois Press, Illinois, 144pp.

Sharma, G. (2009). Agro-ecological diversity, ecosystem services and impacts of climate change in the Indigenous Farming Systems of the Sikkim Himalayas. Journal of Hill Research 22(2): 68–85.

Sharma, G. & B.K. Acharya (2013). Agriculture systems and management diversity, pp. 225–259. In: Kharel, S., & J. Bhutia (eds.). Gazetteer of Sikkim. Gangtok, Sikkim: Home Department, Government of Sikkim.

Sharma, G., U. Partap, E. Sharma, G. Rasul & R.K. Avasthe (2016). Agrobiodiversity in the Sikkim Himalaya: sociocultural significance, status, practices, and challenges. ICIMOD Working Paper. Kathmandu: International Centre for Integrated Mountain Development (ICIMOD).

Shrestha, U. B., S. Shrestha, P. Chaudhary & R.P. Chaudhary (2010). How representative is the protected areas system of Nepal? Mountain Research and Development 30(3): 282–294; http://doi.org/10.1659/MRD-JOURNAL-D-10-00019.1

Singh, A.P. (2010). Butterfly diversity in tropical moist deciduous Sal forests of Ankua Reserve Forest, Koina Range, Saranda Division, West Singhbhum District, Jharkhand, India. Journal of Threatened Taxa 2(9): 1130–1139; http://doi.org/10.11609/JoTT.o2274.1130-9

Singh, A.P. (2017). Butterflies associated with major forest types in Arunachal Pradesh (Eastern Himalaya), India: Implications for ecotourism and conservation planning. Journal of Threatened Taxa 9(4): 10047–10075; http://doi.org/10.11609/jott.2765.9.4

Sondhi, S., K. Kunte, G. Agavekar, R. Lovalekar & K. Tokekar (2013). Butterflies of the Garo Hills. Samrakshan Trust, New Delhi, Titli Trust, Dehradun, and Indian Foundation for Butterflies, Bengaluru, 200pp.

Sondhi, S. & K. Kunte (2016). Butterflies (Lepidoptera) of the Kameng Protected Area Complex, western Arunachal Pradesh, India. Journal of Threatened Taxa 8(8): 9053–9124; http://doi.org/10.11609/jott.2984.8.8.9053-9124

Steffan-Dewenter, I. & T. Tscharntke (1997). Early succession of butterfly and plant communities on set-aside fields. Oecologia 109: 294–302; http://doi.org/10.1007/s004420050087

Tiple, A.D. (2012). Butterfly species diversity, relative abundance and status in Tropical Forest Research Institute, Jabalpur, Madhya Pradesh, Central India. Journal of Threatened Taxa 4(7): 2713–2717; http://doi.org/10.11609/JoTT.o2656.2713-7

Tscharntke, T., A.M. Klein, A. Kruess, I. Steffan-Dewenter & C. Thies (2005). Landscape perspectives on agricultural intensification and biodiversity - ecosystem service management. Ecology Letters 8(8): 857–874; http://doi.org/10.1111/j.1461-0248.2005.00782.x

Uniyal, V.P. (2004). Butterflies of Nanda Devi National Park - a World heritage site. The Indian Forester 130(7): 800–804.

Uniyal, V.P. (2007). Butterflies in the Great Himalayan Conservation Landscape in Himachal Pradesh, Western Himalaya. Entomon 32(2): 119–127.

Uniyal, V.P. & P.K. Mathur (1998). Diversity of butterflies in the Great Himalayan National Park, Western Himalaya. Indian Journal of Forestry 21: 150–155.

Venter, O., R.A. Fuller, D.B. Segan, J. Carwardine, T. Brooks, S.H.M. Butchart & J.E.M. Watson (2014). Targeting global protected area expansion for imperiled biodiversity. PLoS Biology 12(6): e100189; http://doi.org/10.1371/journal.pbio.1001891

Vu, L.V. (2009). Diversity and similarity of butterfly communities in five different habitat types at Tam Dao National Park, Vietnam. Journal of Zoology 277: 15–22; http://doi/10.1111/j.1469-7998.2008.00498.x

Vu, L.V. (2013). The effect of habitat disturbance and altitudes on the diversity of butterflies (Lepidoptera: Rhopalocera) in a tropical forest of Vietnam: results of a long-term and large-scale study. Russian Entomological Journal 22(1): 51–65.

World Bank (2017). Agriculture land (% of land area). The World Bank, Washington, DC. http://data.worldbank.org/indicator/AG.LND.AGRI.ZS accessed on 27 September 2017.

Wynter-Blyth, M.A (1957). Butterflies of the Indian Region. The Bombay Natural History Society, Bombay, India, 523pp.

Appendix I. Butterflies observed in three ecosystems of southern Sikkim, eastern Himalaya including their habitat, larval host specificity and larval host plant. Number represents the abundances of butterflies observed during the study.

	Species	Scientific name	FAS	LCAS	NFS	Total	^$Habitat	Larval host specificity	Larval host plants species and family
	Hesperiidae
1	Common Small Flat	Sarangesa dasahara Moore, 1866	-	-	2	2	FI	Monophagous	Asystasia macrocarpa (Acanthaceae)
2	Spotted Demon	Notocrypta feisthamelii Boisduval, 1832	-	2	2	4	FI	Oligophagous II	Curcuma aromatica, Hedychium acuminatum (Zingiberaceae)
	Lycaenidae
3	Azure Sapphire	Heliophorus moorei Hewiston, 1856	5	1	3	9	FE + OL	-	-
4	Common Cerulean	Jamides celeno Cramer, 1775	-	6	-	6	OL	Oligophagous II	Butea monosperma, Crotolaria spp., Derris indica, Pongamia pinnata, Xylia xylocarpa (Fabaceae)
5	Dark Cerulean	Jamides bochus Stoll 1782	1	-	3	4	FE + OL	Oligophagous II	Butea monosperma, Crotalaria albida, Crotalaria ferruginea, Crotalaria mucronata, Pongamia pinnata, Xylia xylocarpa (Fabaceae)
6	Golden Sapphire	Heliophorus brahma Moore 1857	4	-	1	5	FE	Oligophagous II	Polygonum nepalense, Rumex nepalensis (Polygonaceae)
7	Malayan	Megisba malaya Horsfield, 1828	-	2	-	2	FE	Monophagous	Allophylus cobbe (Sapindaceae).
8	Metallic Cerulean	Jamides alecto Felder, 1860	76	38	34	148	OL	Oligophagous II	Boesenbergia rotunda, Elettaria cardamomum (Zingiberaceae)
9	Pale Grass blue	Pseudozizeeria maha Kollar, 1844	7	1	-	8	OL	Polyphagous	Strobilanthes capitatus, Strobilanthes roseus, Strobilanthes thomsoni (Acanthaceae); Oxalis corniculata (Oxalidaceae)
10	Pea Blue	Lampides boeticus Linnaeus, 1767	7	-	9	16	FE + OL	Oligophagous II	Butea minor, Crotalaria albida, Crotalaria ferruginea, Crotolaria mucronata (Fabaceae)
11	White Cerulean	Jamides pura Moore, 1886	2	-	-	2	OL	-	-
	Nymphalidae
12	Banded Treebrown	Lethe confusa Aurivillis, 1898	-	-	1	1	FI	Monophagous	Poa annua (Poaceae)
13	Blue Tiger	Tirumala limniace Cramer, 1775	2	-	1	3	OL + FE	Oligophagous II	Calotropis gigantea, Calotropis procera, Asclepias curassaviva (Apocynaceae)
14	Common Bushbrown	Mycalesis perseus Fabricius, 1775	2	-	4	6	FI	Oligophagous II	Apluda mutaca, Elusine coracan, Oryza sp., Sorghum sp.(Poaceae)
15	Common Crow	Euploea core Carmer, 1780	1	-	-	1	OL + FE	Polyphagous	Barleria prionitis (Acanthaceae); Nerium odorum (Apocynaceae); Ficus benghalensis, Ficus religiosa (Moraceae)
16	Common Sailer	Neptis hylas Linneaus, 1758	4	-	5	9	OL + FE	Polyphagous	Bombax ceiba (Malvaceae); Elaeocarpus lanceifolius (Elaeocarpaceae); Dalbergia sissoo, Dalbergia stipulacea (Fabaceae); Grewia sapida (Malvaceae)
17	Common Tiger	Danaus genutia Cramer, 1779	-	3	3	6	OL + FE	Oligophagous II	Asclepias curassavica, Ceropegia lawii, Ceropegia spp. (Apocynaceae)
18	Dark-brand Bushbrown	Mycalesis mineus Linneaus, 1758	-	-	3	3	FE	Oligophagous II	Lopantherum spp., Pogonontherum spp., Microstegium spp. (Poaceae)
19	Glassy Tiger	Parantica aglea Stoll, 1782	-	1	-	1	FI	Oligophagous II	Ceropegia bulbosa, Cryptolepis buchananii, Tylophora carnosa, (Apocynaceae)
20	Great Evening Brown	Melanitis zitenius Herbst, 1796	-	1	-	1	FI	Oligophagous II	Bambusa arundinacea, Ochlandra sp. (Poaceae)
21	Great Silverstripe	Argynnis childreni Gray, 1831	2	-	-	2	OL	Polyphagous	Mentha longifolia (Lamiaceae); Buddleja asiatica (Buddlejaceae); Viola diffusa, Viola serpens, Viola tricolor (Violaceae); Rubus niveus (Rosaceae)
22	Green Commodore	Sumalia daraxa Doubleday, 1848	-	4	2	6	FE	Oligophagous II	Populus gamblei, Populus glauca, Salix tetrasperma, Salix salwinensis (Salicaceae)
23	Himalayan Fivering	Ypthima sakra Moore, 1857	4	-	8	12	FE	Monophagous	Digitaria ciliaris (Poaceae)
24	Himalayan Jester	Symbrenthia brabira Moore, 1872	-	-	1	1	FI	Oligophagous II	Debregeasia longifolia, Elatostema grande (Urticaceae)
25	Indian Fritillary	Argynnis hyperbius Linnaeus, 1763	4	-	-	4	OL	Polyphagous	Tagetes patula, Zinnia sp. (Asteraceae); Antirrhinum majus (Plantaginaceae); Fagopyrum sp. (Polygonaceae); Viola diffusa, Viola serpens, Viola tricolor (Violaceae)
26	Indian Red Admiral	Vanessa indica Herbst, 1794	14	2	-	16	OL	Polyphagous	Digitalis purpurea (Plantaginaceae); Urtica dioica, Boehmeria diffusa, Boehmeria glomerulifera, Boehmeria penduliflora, Girardinia diversifolia (Urticaceae)
27	Indian Tortoiseshell	Aglais caschmirensis Kollar, 1844	68	20	17	105	OL	Oligophagous I	Urtica dioica, Urtica parviflora (Urticaceae)
28	Large Yeoman	Cirrochroa aoris Doubleday, 1847	-	-	1	1	FI	Monophagous	Hydnocarpus sp. (Achariaceae)
29	Orange Oakleaf	Kallima inachus Doyere, 1840	-	-	1	1	FI+FE	Polyphagous	Strobilanthes cuspidatus (Acanthaceae); Prunus persica (Rosaceae); Polygonum orientale (Polygonaceae); Girardinia diversifolia (Urticaceae)
30	Painted Lady	Vanessa cardui Linnaeus, 1758	49	13	15	77	OL + FE	Polyphagous	Artemisia sp., Blumea sp., Echinops echinatus, Gnaphalium affine, Gnaphalium sp. (Asteraceae); Zornia diffusa, Zornia gibbosa (Fabaceae); Argemone mexicana (Papaveraceae); Boehmeria diffusa, Debregeasia bicolor, Girardinia diversifolia (Urticaceae)
31	Plain Tiger	Danaus chrysippus Linnaeus, 1758	-	-	1	1	OL + FE	Oligophagous II	Asclepias curassavica, Calotropis gigantea, Cryptolepis buchananii, Ceropegia sp. (Apocynaceae)
32	Himalayan Queen Fritillary	Issoria isaeea Gray, 1846	13	1	5	19	OL + FE	Polyphagous	Viola diffusa (Violaceae); Taraxacum officinale (Asteraceae)
33	Red Lacewing	Cethosia biblis Drury, 1770	-	-	2	2	FI+FE	Oligophagous I	Passiflora cochinchinensis, Passiflora moluccana, Passiflora sp. (Passifloraceae)
34	Scarce Woodbrown	Lethe siderea Marshall, 1880	-	3	-	3	FI	-	-
35	Straight-banded Treebrown	Lethe verma Kollar, 1884	-	-	5	5	FI	Monophagous	Arundinaria aristata (Poaceae)
36	Yellow Coster	Acraea issoria Hubner, 1881	7	-	-	7	OL + FE	Polyphagous	Boehmeria sp., Pouzolzia hirta (Urticaceae); Buddleja asiatica (Buddlejaceae)
	Papilionidae
37	Common Peacock	Papilio bianor Cramer, 1777	-	1	1	2	OL + FE	Oligophagous II	Zanthoxylum armatum, Zanthoxylum achanthopodium, Clausena sp., Citrus spp. (Rutaceae)
	Pieridae
38	Common Grass Yellow	Eurema hecabe Linnaeus, 1758	2	5	9	16	OL + FE	Oligophagous II	Acacia gageana, Acacia pennata, Albizia procera, Caesalpinia sp., Cassia fistula, Cassia mimosoides, Cassia siamea, Cassia tora, Moullava spicata, Pithelobium dulce (Fabaceae)
39	Common Jezebel	Delias eucharis Drury, 1773	1	-	1	2	OL + FE	Oligophagous II	Dendrophthoe falcata, Loranthus longiflorus, Loranthus elasticus, Scurrula sp. and Viscum sp. (Loranthaceae)
40	Dark Clouded Yellow	Colias fieldii Menetries ,1855	56	9	17	82	OL + FE	Polyphagous	Trifolium repens, Indigofera sp. (Fabaceae); Rubus sp. (Rosaceae)
41	Indian Cabbage white	Pieris canidia Linneaus, 1786	142	65	81	288	OL + FE	Oligophagous II	Rorippa dubia, Rorippa indica, Brassica juncea, Sisymbrium sp. (Brassicaceae)
	Riodinidae
42	Dark Judy	Abisara fylla Westwood, 1851	-	-	15	15	FI	Monophagous	Maesa chisia (Myrsinaceae)
43	Punchinello	Zemeros flegyas Bosiduval, 1836	1	-	4	5	FE	Oligophagous I	Maesa chisia, Maesia indica, (Myrsinaceae)
44	Striped Punch	Dodona adonira Hewitson, 1866	-	1	1	2	FE	Monophagous	Maesa chisia (Myrsinaceae)
	Total species richness		24	20	32	44
	Total abundance		474	179	258	911

^$ Habitat specialization: FI (Forest interior only), FI+FE (Forest interior + Forest edge), FE (Forest edge only), FE + OL (Forest edge+ Openland), OL (Openland only).

FAS- farm-based agroforestry system; LCAS- large cardamom-based agroforestry system; NFS- natural forest.

Data source: Haribal 1992; Kunte 2000; Barua 2007; Kunte et al. 2017; Kehimkar 2008; Tiple 2012; Sengupta et al. 2014; and field observations.

Figures indicate the number of individual butterflies observed during the study.