Seasonal Diversity and Distribution of Butterflies in G.Venkataswamy Naidu College Campus, Kovilpatti, Tuticorin District, Tamil Nadu

This study was conducted to prepare a baseline inventory, seasonal population trends and status of butterfly inhabiting the campus of G. Venkataswamy Naidu College, Kovilpatti, Tuticorin. The survey yielded 309 individuals of 48 butterfly species, belonging to the families Nymphalidae, Pieridae, Lycaenidae, Papilionidae and Hesperiidae. Nymphalidae were found to be the dominant family during all seasons. Species abundance was highest during the northeast monsoon and winter periods. The maximum number of 163 individuals was sampled during the NE monsoons followed by winter 109 individuals and SW Monsoon showed 23 individuals. The summer showed least skewed 15 individuals were recorded. The butterfly species composition and relative abundance belonged to the families Namphalidae (17 Species; 35.42%), Pieridae (11 species; 25.00%), Lycaenidae (7 Species; 14.58%), Papilionidae (8 Species; 16.67%) and Hisperiidae (4 Species; 8.33%). The maximum number of butterfly species and maximum number of individuals were sampled during the monsoons, indicating that, the southern plains area of India butterflies prefer cool seasons for breeding and emergence. Three endemic species like Cepora nerissa, Troides minos and Atrophaneura hector and seven protected species like Euploea core , Cepora nerissa , Appias albino , Castalius rosimon , Euchrysops cnejus , Troides minos and Atrophaneura hector were listed under the Wildlife Protection Act 19720. These species highlighted greater importance of conservation in college campus. A checklist of butterfly species is also provided. The observation will support the detailed study of ecologically important local butterfly fauna of the college campus in Kovilpatti which provide a valuable resource to nature.


Introduction
Butterflies are one of the most conspicuous species of Earth's biodiversity [1]. Butterflies are generally regarded as the best taxonomically studied groups of insects due to their great aesthetic value owing to bright colors, interesting behaviors and daytime activity periods [2]. Buttetflies are extremely important components of the bioindicators [3].It is often used as bio-indicators of ecosystem health and as surrogates for overall biodiversity [4] and are widely used as sensitive indicators of environmental change, temperature and humidity caused by disturbances in its habitats [5].Institutional 92 Seasonal Diversity and Distribution of Butterflies in G.Venkataswamy Naidu College Campus, Kovilpatti, Tuticorin District, Tamil Nadu campuses with undisturbed vegetation and seasonal flowering provide potential habitat for butterfly population [6]. Food of butterfly plays an important role in determining their distribution, abundance and movement [7]. Positive relationships have been found between butterfly diversity and plant diversity [8]. A large proportion of the plant species including many trees depends on insects to pollinate their flowers (9). Totally, 252 wild and planted species of flora were recorded in G.V.N. College Campus [10]. Conservationist, mainly focus on vertebrates but many invertebrate species are at risk. [11].The immediate steps need to be taken to protect invertebrates and restore invertebrate diversity and habitat. Moreover, the information available is mostly restricted to some protected areas and there is a need to study these organisms particularly at institutional campuses. Hence, the objective of this study is to create baseline information on diversity and distribution pattern of lepidopteron fauna communities present at G.V.N. College campus, Kovilpatti.

Materials and Methods i) Inventory of Fauna
The inventory of lepidopteran faunal diversity in G. Venkataswamy Naidu College, Kovilpatti, Tuticorin (9 0 11'45.35N 77 0 50'04.29E) is a 6E, Deccan Peninsula Deccan South. This study was conducted in the college campus with several line transect of Kovilpattti, Tuticorin district of Tamil Nadu ( Figure 1). The work was carried out over a one year period (September 2018-August 2019). The procedure involved field survey of handful charismatic taxa of butterflies. Identification of butterflies was achieved through photographic evidence. Confirmation of species status was done using identification [12,13]. The butterflies were observed and photographed during the survey period (Plate 1).

ii) Methodology for Butterflies
Sampling was carried out in different seasons South West Monsoon (SWM), North East Monsoon (NEM), Winter and Summer during September 2018-May 2019 covering an entire campus area of about 105ha. A slight modification of the conventional line transect count [14] was adapted to determine butterfly richness and abundance. In this method, six permanent 200m line transects were setup in college campus. The transects were slowly traversed for approximately 10 minute in each transect from 08.00hrs to 09.30hrs during the good weather period (no heavy rain or strong wind). Butterfly species were recorded around a radius of 5 meter from the observer covering all sides laterally and above. This is a suitable method for surveying butterflies in a wide range of habitats all individuals were identified in the field using standard guides [12,13]. No specimen was collected during the study period. Photograph was taken during the field visit using Nikan D 3400.
The interpretation of data was carried out to assess the relative abundance of the butterfly populations. The clustering of species was based on their presence and absence during different seasons was compared by using Bray Curtis similarity matrix (Cluster analysis) were calculated using Biodiversity Pro Version 2 [15].

Result
The study revealed that, total of 309 individuals comprising 36 genera and 48 species of butterflies around the campus of G.V.N College, Kovilpatti (Table 1 & Figure 6). The overall occurrence of maximum number of species in the family Nymphalidae, Pieridae and Lycaenidae were in the study area. Nymphalidae is the dominant family in terms of species composition and abundance with (17 species and 35.42%), Pieridae (11 species, 25.00%), Papilionidae (8 species and 16.67%), Lycaenidae (7 species, 14.58%) and Hesperiidae (4 species, 8.33%). The study revealed the occurrence of 48 species of butterflies belonged to the 36 genera and 5 familie ( Table 2).
The North East Monsoon revealed that highest number of species, Nymphalidae showed (15 species 38.46%), followed by Pieridae (10 species 25.64%), Lycaenidae (7 species 17.54%), Papilionidae (4 species; 10.25%) and Hesperiidae (3 species; 7.69%). Winter season showed Nymphalidae showed (13 species 36.11%), followed by Pieridae (10 species 27.77%), Lycaenidae (6 species 16.66%), Papilionidae (4 species; 11.11%) and Hesperiidae (3 species; 8.33%). South West Monsoon showed Nymphalidae showed (6 species 50.00%), followed by Pieridae (3 species 25.00%) and Papilionidae (3 species; 25.00%). Summer seasons showed Nymphalidae showed (2 species 40.00%), followed by Pieridae (1 species 20.00%) and and Papilionidae (2 species; 40.00%) figure 2.  The butterfly abundance during different seasons showed that more number of butterflies were observed during the periods of North East Monsoon followed by Winter Figure 3. The NEM showed more number (159 individuals; 51.45%) followed by winter (89 individuals; 28.80%); summer (35 individuals; 11.32%) and SEM (26 individuals; 8.41%).    The similarity of species composition among different seasons has also been presented in Figure. 5. The similarity matrix from the quantitative data showed that taxonomic composition of butterflies was much similar in the NEM and Winter formed a single cluster group with a similarity index value of 60.52%, it indicated that both periods have the similar species composition. The insignificant variability was observed in SWM and summer; it showed that 18-30% similarity. The overall observations made in the present study suggest that seasonal complexity and distribution of butterflies associated with each seasons might act as major drivers and determinants of the patterns of butterfly assemblages in college campus.

Discussion
The present study revealed that highest number of individuals in North East Monsoon followed by Winter, Summer and South West Monsoon. Nymphalidae were the most common with 17 species, followed by the Pieridae (11 species), Papilionidae (8 species) Lycaenidae (7 species), and the least number of species was observed in Hesperiidae only 4 species. The same pattern of predominance of nymphalidae was reported by different researchers (Eswaran andPramod, 2005 andPramod et al., 2007) (16,17). The reason for the extraordinary abundance of pieridae butterfly in the study area can be achieved to the dominance of their larval food pants in the region (Balasubramaniam et al. 2001) [18] and the butterfly diversity in various institutional campuses and research institutes showed a similar pattern of predominance of Nymphalidae followed by Pieridae, Lycaenidae, Papilionidae and Hispeiridae were also reported by different researchers [17,18,19,20,21]. (19,20,21,22,23) The dominance of Nymphalidae species may be attributed to their ability to forage on various kinds of plants, being a polyphagous species and many species of this family are active fliers and thus forage wide areas it is one of the important ecological advantages. Similar patterns of observation recorded in [Majumder et al., 2013] (24). This is consistent with Nymphalidae being the largest butterfly family, accounting for one third of known species worldwide (Tiple, 2011). (25) However, in the present study, Lycaenidae and Hesperidae were poorly represented in the study area, which reported members of Hesperiidae to be least represented. One of the possible reasons for this difference could be due to the difficulties in observing 98 Seasonal Diversity and Distribution of Butterflies in G.Venkataswamy Naidu College Campus, Kovilpatti, Tuticorin District, Tamil Nadu Hesperiidae butterflies because of their dull color. Lycaenidae also very less species and individual abundance due to the foraging herb absent in the Summer and South West Monsoon. The abundance of species and individuals were high during North East Monsoon 39 species and 163 individuals, whereas 36 species, 109 individuals were observed only from winter. The same pattern of increasing species abundance and individual abundance from the beginning of the monsoon till early winter and decline in species abundance from late winter to the end of summer have also been reported by Tiple et al. (2007) [26] and Tiple & Khurad (2009) [27].
Majority of species and individuals were observed, the possible reasons include increased availability and variety of host plants. The distribution and diversity of butterflies varies depends upon the seasons. They are abundant in some months and absent during months   (7). This has been reported in other studies (Qureshi et al. 2013) (28). The greatest number butterflies in the study area might be the adequate distribution of larval host plants and nectar [24] (29) and vegetation cover and good food sources for many butterfly species [25] (30).
A total of three species of endemic and seven species of butterflies from the study area are designated as Wildlife Protection Act (WPA 1972) while describing their status and justifies its inclusion in scheduled list suggesting the need for strict conservation measures. The objective revision of the scheduled list will be very useful in providing appropriate and adequate legal protection to Indian [7]. Nine species are accorded highest protection under the Indian Wildlife Act, 1972 [31] (Anonymous 1972)

Conclusion
This study reveals that to enrich the information and knowledge available on the butterflies of G. Venkatswamy Naidu College campus. The maximum number of butterfly species and maximum number of individuals were sampled during the monsoons, indicating that in the southern plains area of India butterflies prefer cool seasons for breeding and emergence. The rich diversity of butterflies, especially the nymphalids, pieridae and lycaenidae in the study area indicates a varied assemblage of floral species. The butterflies sampled resemble that of the Western Ghats and other regions of India in two ways 1) dominance of nymphalids and 2) peak abundance during wet seasons. The finding of the present study is to recommend the importance of institutional campuses as a preferred habitat for butterflies like endemic and protected species. This information will help in future research work on butterflies larval host plants preference for launching conservation strategies. It will helpful to owing carefully planned in larval host plants maintenance in gardens, the diversity of butterflies may increase in the college campus providing excellent knowledge for butterfly conservation as well as for future research.