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A preliminary assessment of the diversity and ecosystem preference of spider families occurring in Kanha Tiger Reserve

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A scanned version of the paper I presented at the National Workshop on Diversity & Taxonomy of Spiders with special reference to Molecular Systematics (Akola. Maharashtra. 2014). Original softcopy is unavailable.

Abstract: Spiders (Arachnida: Araneae) are one of the ubiquitous and generalist predators that occupy virtually every niche in a terrestrial ecosystem. The diversity of spiders of Kanha Tiger Reserve was studied at the family-level during summer months to understand their ecosystem preferences in the reserve. A total of 20 families were recorded during the study. Four ecosystems, namely Sal dominant forests (SD), mix deciduous forests (MD), bamboo dominant forests (BD), and grasslands (GL) were selected as distinct ecosystems inhabited by spiders. The study revealed that the family-level diversity and density was higher in SD, followed by MD, BD, and GL. Among the spider families, we observed higher relative abundance of Oxyopidae in SD and GL, Salticidae in MD and Lycosidae in BD. This paper looks at spider families as an individual unit, their ecosystem preferences in the purview of the larger diversity of Kanha Tiger Reserve, and at the first records of spider families, viz. Deinopidae, Ctenidae, and Coriniidae from Madhya Pradesh.

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A preliminary assessment of the diversity and ecosystem preference of spider families occurring in Kanha Tiger Reserve

  1. 1. National Symposium cum Workshop on Diversity of Spiders with Special Reference 26'“ — 29”‘ L» :3 to Taxonomy & Molecular Systematics — 2014 ISBN :978-81-929160-5-7 November A PRELHVIINARY ASSESSMENT OF THE DIVERSITY AND ECOSYSTEM PREFERENCE OF SPIDER FAMILIES (ARACHNIDA: ARANEAE) OCCURRING IN KAN HA TIGER RESERVE Aniruddha Dhamorikar', Kedar Gorez ‘Programme Officer, 2Director, The Corbett Foundation Village Baherakhar, Post Nikkum, Block Birsa, District Balghat, Madhya Pradesh 481 1 1 1 ABSTRACT Spiders (Arachnida: Araneae) are one of the ubiquitous and generalist predators that occupy virtually every niche in a terrestrial ecosystem. The diversity of spiders of Kanha Tiger Reserve was studied at the family-level during summer months to understand their ecosystem preferences in the reserve. A total of 20 families were recorded during the study. Four ecosystems, namely Sal dominant forests (SD), mix deciduous forests (MD), bamboo dominant forests (BD), and grasslands (GL) were selected as distinct ecosystems inhabited by spiders. The study'revealed that the family-level diversity and density was higher in SD. followed by MD, BD, and GL. Among the spider families, we observed higher relative abundance of Oxyopidae in SD and GL, Salticidae in MD and Lycosidae in BD. This paper looks at spider families as an individual unit, their ecosystem preferences in the purview of the larger diversity of Kanha Tiger Reserve and as the first records of spider families, viz. Deinopidae, Ctenidae, and Coriniidae from Madhya Pradesh. I(eywords: Spider, diversity, ,ecosystem, Kanha Tiger Reserve, Madhya Pradesh INTRODUCTION Spiders (Arachnida: Araneae) are one of the significant groups of obligate camivorous invertebrates occupying virtually every niche in a terrestrial ecosystem (Turnbull, 1973). The role played by spiders is crucial in ecological studies since spiders are extremely sensitive to small changes in habitat structure, including vegetation complexity. litter depth and microclimate characteristics. Furthermore their high relative abundance and diversity in habitat preferences and foraging strategies allows for effective monitoring of site differences (Uetz, 1991 and Yen, 1995, cited in Hore and Uniyal, 2008, p. 1371). Hence. spiders have been proposed as indicator species (Churchill, 1998; Sebastian and Peter, 2009). A total of 60 spider families have been recorded from India (Keswani et al, 2012) of which 22 families have been recorded in Madhya Pradesh as per Patil (2011). The current study identified 20 spider families in Kanha Tiger Reserve (KTR), including three, viz. Deinopidae, Ctenidae, and Coriniidae as first records for Madhya Pradesh, summing the total number of families from Madhya Pradesh to 25. Spider fauna of KTR has been poorly studied, with only one published record of the efforts made by Gajbe (1995). A study focusing on entomology of Kanha National Park was Dept. of Zoology, Shankarlal Khandelwal Arts, Science & Commerce College, Akola (M. S.)
  2. 2. National Symposium cum Workshop on Diversity of Spiders with Special Reference to Taxonomy & Molecular Systematics — 2014 ISBN :978-81-929160-5-7 2014 26th _ 29111 I November W undertaken by Tropical Forestry Research Institute (TFRI) in 2004, however no effort has been made to map the diversity and ecology of spiders in KTR. With respect to KTR’s diverse mega-fauna, the role played by invertebrates is often overlooked, albeit the fact that they play a pivotal role in a number of ecological fiinctions including decomposition, pollination, pest-control, and as indicator species of an ecosystem. Spiders being predatory in nature, play a crucial role as population—controllers of insects (Sebastian and Peter, 2009). This study is an effort to identify ecosystem preferences of spiders in the four major ecosystems of KTR, viz. , Sal-dominant forests, mix-deciduous forests, bamboo-dominant forests, and grasslands. Through this study we are trying to understand the diversity of spiders and the reasons for their distribution. MATERIAL AND METHODS Study Area: The study was undertaken for four months, during February to May, 2014. Permissions were obtained from the Chief Wildlife Warden, Forest Department of the Government of Madhya Pradesh, and Field Director, Kanha Tiger Reserve to undertake the study. The study area comprised of buffer and core-zone of Kanha Tiger Reserve (KTR) between 22°7' to 22°27'N and 80°26’ to 8l°3'E. It forms a part of the Satpuda~Maikal Landscape, and is famed for its conservation measures taken for the endangered Hard- Ground Barasingha (Cervus duvauceli branderz) and Tiger (Panthera tigris tigris). The temperatures recorded during the study ranged from 19.5°C to 45°C, with relative humidity recorded between 10% and 91.3%. Survey techniques: Field surveys using quadrat sampling method and transect walk was carried out in four ranges of KTR, viz. Mukki, Samnapur, Khatia, and Khapa. Transects of 1 km length were outlaid in the study area along with quadrats of 2 x 2 m. A total of 36 transects and 180 quadrats were surveyed to study the diversity and density of spiders. Random sampling was conducted to ascertain the total number of families present in KTR. A quadrat of 10 x 10 m was surveyed specifically to study the composition of trees to identify the type of ecosystem. Four distinct ecosystems were identified based on the presence of the dominant trees (Table 1). Table 1: Types of ecosystem showing percent composition of dominant flora: Types of ecosystem Percent composition of dominant flora Ecosystem characteristics Sal-dominant forest (SD) Sal (Shorea robusta): 72.57% Characterized by Sal Saja (Terminalia t0ment0sa): 5.06% trees which remain Sindoor (Mallotus phillippensis): green throughout 4.64% summer, providing Moyan (Lannea coromendelica): Shade and 3 m0iSt 4,64% environment. Sal Tinsa (Ogenia o0gez'nensis): 3.37% forests PT0Vide 3 rich Misc. (14 species): 9.72% leaflitter and are Dept. of Zoology, Shankarlal Khandelwal Arts, Science & Commerce College, Akola (M. S.)
  3. 3. 26”‘ — 29'“ : r November % 2014 ' ‘ I'M’ leafless only for a short duration. (Kishen, 2014) National Symposium cum Workshop on Diversity of Spiders with Special Reference to Taxonomy & Molecular Systematics ~ 2014 ISBN 3978-81-929160-5,-7 Mix-deciduous forest (MD) Saja (T erminalia tomentosa): 19.42% Characterized by Dhava (Anogeissus latif0lia): 1 1.03% deciduous trees that Lendia (Lagerstroemia parvif0lia): Shed their 1eaVeS 623% between February and May. Such forests are Tendu (Diospyros melan0xyl0n): usually dr)’ during 431% summer. (Kishen, Misc. (29 species): 53.02% 2014) Bamboo-dominant forest (BD) Bamboo (Dendrocalamus strictus): 55.26% bamboo dominance Palash (Butea monosperma): 15.78% are generally seen Bauhinia valhii: 13.15% along mountain Misc. (6 species): 15.81% s1opes- Dry bamboo leaves provide a thick leaf litter. Summer ' climate is usually dry with low relative humidity. Forests with high Grassland (GL) Grasses and miscellaneous herbs Characterized by grasses, seen in meadows and plateaus with no tree-cover, poor leaf litter, and subject to intense temperatures during summer. Spiders were individually counted on transects and quadrats and grouped according to their family. Non-invasive method was employed and no specimens were collected. Photographs were obtained using Canon 60D camera, 18-55mm lens fitted with micro-filter, for the confirmation of identifications. Identifications up to family-level were possible by observing the eye-pattems of the spiders. Genus-level identifications, wherever possible, were confirmed using literature from Sebastian and Peter (2009). Literature was also reviewed especially for the Central Indian region. Data analysis: Data was collected and collated into number of individual spiders observed per family in the identified ecosystems. Percent relative abundance for each ecosystem was calculated by deducing the percentage of the number of individuals per family with the total number of individuals from all families present in an ecosystem. Dept. of Zoology, Shankarlal Khandelwal Arts, Science & Commerce College, Akola (M. S.)
  4. 4. National Symposium cum Workshop on Diversity of Spiders with Special Reference to Taxonomy & Molecular Systematics — 2014 ISBN :978-81-929160-5-7 26"‘—29”‘ 4 November % 2014 Results and Discussion The study revealed presence of 20 spider families (Table 2), of which three, viz. , Deinopidae, Ctenidae, and Coriniidae are new additions to the checklist of the spiders of Madhya Pradesh. A total of 13 families were recorded during quadrat and transect survey and seven during random surveys. The data presented in this study is from the quadrat and transect survey, which was primarily undertaken to ascertain the ecology of spider families in KTR. Table 2: List of spider families recorded during quadrat surveys and random sampling in KTR: 1‘ Z I H Gnaphosidae -7. Theridiidae - H Tetragnathidae - TX I I '2' I I ——Z 5 milies recorded during random sampling Nephiliidae I I IIE IIE III ’ ‘ “ ‘H E! ' S: III! III IIII E I) H 1 5. Pholcidae E: Z T- Z I . _— The ecosystem-wise family diversity (Figure 1) revealed SD to be more diverse in terms of family representation as well as density, followed by MD. BD showed higher family diversity and density than GL. Dept. of Zoology, Shankarlal Khandelwal Arts, Science & Commerce College, Akola (M. S.) N 65 ll I
  5. 5. National Symposium cum Workshop on Diversity of Spiders with Special Reference 26"‘ — 29"‘ -- _'~J to Taxonomy & Molecular Systematics — 2014 ISBN :978-81-929160-5-7 November % 2014 Bamboo-dominant Grassland (G L) — (BD) — 7 Families_ F 5 Families 10% 2% Mix- deciduous sai- (MDl - 10 dominant Families (50) - 12 34% Families 54% Figure 1: Ecosystem-wise density and diversity of spider families of KTR SD recorded the highest number of families (12 out of 13), along with the highest number of individuals counted (54%), followed by MD (34%), BD (10%), and GL (2%). Family-level diversity was relatively higher in SD and MD, and low in BD and GL probably because of the lack of shade and high temperatures during summer months. The overall dominant families according to the number of individuals recorded were Oxyopidae (31.3%), Lycosidae (30%), and Salticidae (27%). Other families constituted 11.7% of the total. As per the percent relative abundance calculated for each ecosystem (Figure 2), Oxyopidae was found to be most dominant in SD and GL, Salticidae in MD, and Lycosidae in BD. It was observed that forest-type plays a significant role in determining the ecology of spiders. Although the three prominent families, viz. Oxyopidae, Lycosidae, and Salticidae, were present in all ecosystems, they showed significantly higher densities in either of the ecosystems. The higher diversity and density of spiders in SD forests can be attributed to Sal (Shorea robusta) trees which remain green throughout summer, thus provide shade, retain moisture, and a dense-to-moderate groundcover predominated by Sal leaf litter. MD forests were represented by deciduous trees. In such forests temperatures are high and moisture low during summer, this is perhaps the reason for low diversity in comparison to SD. BD forests are dry for the most part of summer and subject to high temperature, yet provide considerable amount of shade in comparison to GL which is dry and subject to intense temperatures during summer. The most abundant members of Oxyopidae, Lycosidae, and Salticidae occupied a similar niche of forest undergrowth, i. e. forest floor; hence their role in the undergrowth as strictly predatory invertebrates is noteworthy. In comparison to the presence of other predatory invertebrates which were surveyed alongside spiders, such as Praying Mantis Dept. of Zoology, Shankarlal Khandelwal Arts, Science & Commerce College, Akola (M. S.)
  6. 6. 15» National Symposium cum Workshop on Diversity of Spiders with Special Reference 26"‘ — 29”‘ A to Taxonomy & Molecular Systematics — 2014 ISBN :978-81-929160-5-7 November 2014 (Insecta: Mantodea), Assassin Bug (Insecta: Hemiptera), Dragonflies and Damselflies (Insecta: Odonata), and Ants (Insecta: Hymenoptera), ants, specifically Weaver Ants (Oecophylla smargdina), were found to be most abundant predatory insects in the undergrowth, however it did not seem to affect the density and diversity of spiders sharing the same niche. Random sampling surveys have revealed an additional seven spider families in KTR, however their absence during the quadrat survey might be attributed to habitat specificity and generally low density of these families (Table 2). 9 120 . »// .:6’. <.:1.'. :; mi - ' " "“‘ '9 55 . 4.4 33 16 I 0 80 21.4 31.6 157 35.1 60 21 29.7 35.4 40 29.3 47.3 20 37.2 22.7 24 ’ SD MD BD GL goxyopidae Lycosidae Salticidae Araneidae Others Figure 2: Ecosystem-wise percent relative abundance of 4 major spider families Conclusion Spiders, although ubiquitous in nature and active hunters of an array of life—forms, show a distinct preference of certain ecosystems at family-level. In addition to biotic factors such as availability of prey-base as well as competition from other predatory invertebrates, ecosystem-specific preference is mainly attributed to abiotic factors, including availability of shade, temperature, humidity, and rainfall (Lubin, 1978; Churchill, 1998). The study which was conducted during summer months reveals a distinct picture of spider ecology as compared to monsoon or winter months when spider diversity is higher and overlapping owing to the availability of favourable biotic and abiotic factorsdiscussed above. The micro-fauna of KTR, especially that of invertebrates is poorly studied, leaving a lacuna in understanding their ecological role in an environment. Since spiders are almost entirely predatory in nature, their significant representation during the study may represent a rich Dept. of Zoology, Shankarlal Khandelwal Arts, Science & Commerce College, Akola (M. S.) :7,
  7. 7. National Symposium cum Workshop on Diversity of Spiders with Special Reference 26"‘ — 29"‘ _xJ to Taxonomy & Molecular Systematics — 2014 ISBN :978-81-929160-5-7 November % 2014 food-web system, where spiders are symbolic of tigers of the undergrowth by feeding upon insects, especially those that are considered pests. Studies undertaken during all the three seasons of summer, monsoon, and winter will entail a clear picture of spider ecology in KTR. The observations of three families, viz. , Deinopidae, Ctenidae, and Coriniidae serve as new records for Madhya Pradesh as per the checklist created by Patil (2011) and Gajbe (2002). With new species of spiders still being discovered, such as Oxyopes kohaensis and 0. boriensis from Melghat Tiger Reserve (Bodkhe and Vankhede, 2012), and Deniopis scrubjunglei (Caleb et al. 2014) from Chennai, it is likely that KTR may also harbour yet- undiscovered species of spiders. Further studies focusing on the habitat-use and niche-preference, competition for food and space, and role of abiotic factors such as temperature and humidity, along with taxonomic research, are required to understand the ecological role played by spiders. This study therefore serves as baseline information for future studies to help determine the diversity and the role of spiders in the ecosystem functioning of KTR. Acknowledgments The authors are thankful to Mr. Narendra Kumar, IFS, Chief Wildlife Warden, Forest Department (Govemment of Madhya Pradesh); Mr. J. S. Chauhan, IFS, Field Director, Kanha Tiger Reserve; and Mr. Rajneesh Singh, Assist. Director, Kanha Tiger Reserve, for providing permission and support for undertaking this study. The authors thank the Range Officers and the Forest Guards for their hospitality and eagerness towards studying the invertebrate fauna of KTR. The authors extend their gratitude to Dr. Goldin Quadros, Senior Scientist, SACON, and Dr. Amol Patwardhan, Assist. Professor, University of Mumbai, for their valuable feedback. The authors also thank The Corbett Foundation for providing the necessary logistical support for undertaking this study. References Bodkhe, A. K. and Vankhede, G. N. (2012). On two new species of spiders of the genus Oxyopes Latreille from central India (Arachnida: Araneae: Oxyopidae). Indian Society of Arachnology. 1(1). P 150 -155 Caleb, John T. D. and Mathai, Manu Thomas. (2014). A new species of Deinopis MacLeay (Araneae: Deinopidae) from India. Indian Society of Arachnology. 3(1). P 01 — 07 ‘ Churchill, Tracey B. (1998). Spiders as ecological indicators in the Australian tropics: family distribution patterns along rainfall and grazing gradients. In Proceedings of the 17"‘ European Colloquium of Arachnology. Ed. P. A. Selden. P 325 — 330 Gajbe, U. A. (1995). Spider Fauna of Conservation Areas: Fauna of Kanha Tiger Reserve, Madhya Pradesh. Zoological Surcey of India. 27(303) Dept. of Zoology, Shankarlal Khandelwal Arts, Science & Commerce College, Akola (M. S.) 53 I
  8. 8. 26111 _ 29th November % 2014 National Symposium cum Workshop on Diversity of Spiders with Special Reference to Taxonomy & Molecular Systematics — 2014 ISBN :978-81-929160-5-7 Hore, Upamanyu and Uniyal, V. P. (2008). Use of spiders (Araneae) as indicator for monitoring of habitat conditions in Tarai conservation area, India. Indian Forester. P 1371 — 1380 Keswani, S; Hadole, P. , and Rajoria, A. (2012). Checklist of spiders (Arachnida: Araneae) from India -2012. Indian Society ofArachnology 1(1). P 001 — 129 Kishen, Pradip. (2013). Jungle trees of Central India. Penguin Books. Lubin, Y. D. (1978). Seasonal abundance and diversity of web-building spiders in relation to habitat structure on Barro Colorado Island, Panama. Journal of Arachnology. 6. P 31 — 51 Patil, Sachin R. (2011). Spiders of the states of Madhya Pradesh and Chhattisgarh (Arachnida: Araneae): Updated Checklist 201 1. Indian Forester. P 1217 — 1224. Sebastian, P. A. and Peter, K. V. (2009). Spiders of India. Universities Press. Turnbull, A. L. (1973). Ecology of the true spiders (Araneomorphae). Annual Review of Entomology. 18. P 305 — 348. Retrieved from: http: //www. annualreviews. org/ doi/ abs/10.1 146/annurev. en. l8.0l0173.001513 ? journalCode= ento Dept. of Zoology, Shankarlal Khandelwal Arts, Science & Commerce College, Akola (M. S.)

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