Testudines: Major Component of Aquatic Fauna in Aravalli Foothills of Rajasthan (India) & Conservation

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1 Sengupta, M. and Dalwani, R. (Editors). 8 Proceedings of Taal7: The th World Lake Conference: Testudines: Major Component of Aquatic Fauna in Aravalli Foothills of Rajasthan (India) & Conservation Shalini Gaur Desert Regional Station, Zoological Survey of India, Pali Road, Jodhpur (Rajasthan) ABSTRACT The history of Aravalli range states back when important lithographic changes in the atmosphere took place. The part of Aravalli Mountains in Rajasthan bisects the state in two zones, according to the rainfall one is rain shadow and another is rain fed zone. The foothill part of Aravalli comprises big stones and boulders and it is not as a continuous string of mountains but is provided with tunnels made by the action of water, crevices, river beds, grassy as well as barren lands, etc. In rain fed zone appreciable record of rain fall occurs and many naturally made pools flourish density of faunal elements. Floral growth also positively affects the food availability especially for the reptiles as most of them depend upon the agriculture pest and other insects. An array of aquatic fauna small zooplanktons, crustaceans, coelenterates, molluscans, fishes, amphibians and reptiles can be observed in the area. Occurrence of Testudines Lissemys punctata punctata, Trinoyx gangeticus, Hardella thurgi and Kachuga tentoria circumdata in small pockets indicates the possibility of their survival at high extent. Study of their ecology, food and feeding habits and seasonal occurrence can be proved as an important tool towards their conservation. The paper deals with the description of species of testudines with their ecology, relative abundance, their diversity indices in different seasons, habitats, food habits and threats in the area, based on the survey by the author in the Foothills of Aravalli during the year -5. Keywords: Testudines, fresh water, ecology, Rajasthan. INTRODUCTION Important studies have been done by Sharma,, Smith,95, Tikader and Sharma 99 and Minton 966. The Aravalli foothill region of Rajasthan includes some districts completely, while some districts partially come in their range. This vast range provides shelter to many reptile species in different ecological niches. The Aravalli ranges are not arranged in a continuous united chain but these hills are in patches and are interrupted by grass lands, forests, depressions, water holes, runnels, barren areas and sand dunes. All these conditions make the Aravalli foothills a most interesting zone for the study of its floral and faunal elements. At present studies are confined from Sirohi to Beawer and deals with different aspects of reptiles. MATERIALS AND METHODS To study the detailed ecology of testudine species exhaustive surveys were conducted in the different localities of the foothills area in accordance to the season and weather conditions as it is evident that emergence and other activities, upto a large extent depends upon the climatic factors. Visual encounter method was used which involves searching for the animals in an area or habitats (Campbell & christman, 98), recording all visible animals on the surface (Corn & Bury, 99). Entire area was searched intensively at one time (Campbell & christman, 98). This method was followed for detailed ecological observations on different aspects of testudines in Aravalli foothills of Rajasthan. Data was analysed by Handerson for different indices. Observations were taken on time of activity (Diurnal or nocturnal), food and feeding methods, breeding season (pre, main and post breeding season), diversity, modes of foraging, prey availability, microhabitat utilization, predator population and thermoregulation etc. In certain cases animals found dead in road and other accidents, were collected and preserved in 4% formaline. Details of terrain and of vegetation abundance were recorded. For the above studies good binoculars were used for locating the testudines from distance. The equipment like GPS was used for recording exact location and altitude to depict pattern of distribution of the testudines. The specimens were traped measurements were taken and then released again in their habitats. All the specimens were catogorised sub-order wise and identified by Fauna of Reptilia by Sharma () and Smith (95). RESULTS AND DISCUSSION Distribution of testudines in different localities of Aravalli foothills does not follow any regular pattern. The population of the species is found scattered in the Aravalli region of Rajasthan. Among them only few areas were densly populated whearas some other

2 areas did not show even a single individual of any species. The occurrence of the species was not always fixed for any place or habitat as in monsoon season, the areas which comprised good population of testudines hardly encouraged any individual of any species in other season. Here Localities of testudines with their high density and observed behavior is described. Systematic Account Class REPTILIA Order TESTUDINES Family Emydidae Geoclemys hamiltoni (Gray) Localities in Aravalli foothills: Siliburi Dam (6º N, 74º E; alt. 48 m) Habits and habitat: This species was mostly observed in water especially shallow water with weeds. Mainly feeds on small fishes. Two turtles were seen in a pond of stagnant water with a thick growth of algal and other aquatic vegetation in the catchment area of Siliburi Dam. The substratum of this dam is muddy and with plenty of stones scattered all over the bottom providing an ideal shelter for these turtles. Plenty of snails and other aquatic food preferred by these turtles is available in the dam water. Hardella thurgi (Gray) Localities in Aravalli foothills Near Neel Kanth Mahadeo 9 km N. of Beawar (6º 4 44 N, 74º 5 E, alt. 47 mm); Amarpura village, near Rajsamand Lake (5º 55 4 N,.74º 8 E, alt. 47 m.) Habits and habitat I observed the species mostly in stagnant water, mainly in the small tributaries of rivers in the area. The turtle is gentle and docile and stay calmly in its habitat. Its food is mainly leaves, stems and other soft parts of aquatic vegetation. Kachuga tentoria circumdata (Mertens) Localities in Aravalli foothills Sirohi Road (4º 7 7N; 7º 5 E), Nanawas village ca 5 km N. of Pindwara (4º 48 4N; 7º 45 65E), Khajuria village (on bank of Sabarmati river), Udaipur district (4º 97N; 7º 57E). Habits and habitat Mostly found in the slow running fresh water, but at places also observed in stagnant pools. Feeds upon aquatic vegetation. Family Testudinidae Geochelone elegans (Schoepff) Localities in Aravalli foothills: Neel Kanth Mahadeo (6º 4 44N, 74º 5E), Bar Ka Ghata (5º 55 4N, 74º 8E), Sandra (7º 6 4N; 74º 5 4E), Kalka ji Road, Sirohi (4º 7 7N; 7º 5 E), Kolar near Jalor (5º 7 67N; 7º 79E). Habits and habitat: This land tortoise inhabits rocky, grassy areas with plenty of other vegetation. It is quite active during the morning and evening hours of the day and feeds on grass, flowers, wild onions and vegetables. The Geochelone elegans is mostly observed in or around dry leaf liter where they walk very slowly and could be easily traced by the sound of dry leaves caused by the movements of their limbs. The star tortoises prefer to live in slopes of mountains where they stay around densely vegetated areas. They can hide easily by mixing their body pattern with the leaf litters and other dry vegetation. Star tortoises are visible in rainy season in large numbers as they emerge from their abodes and come in open for good food. These tortoises avoid the intense heat and generally move under the cover of shady vegetation. Monsoon is the breeding season of the star tortoise. Family Trionychidae Lissemys punctata punctata (Lacepede) Localities in Aravalli foothills: Silibury Dam (6º N; 74º E), Neel Kanth Mahadeo (6º 4 44N, 74º 5E), Amarpura Village (5º 55 4N; 74º 8E), Bar ka Ghata (5º 55 4N.; 74º 8E), Todgarh (5º 48 49N.; 74º 6 E), Silli Dam (5º 4 7N.; 7º 4 6E), Rajsamand Lake (4º 55 7N.; 7º 5 8E), Bazna Village near Sirohi (4º 48 4N; 7º 45 64E), Purohit Ki Bavri, Sankarna Village (5º 7 67N.; 7º 79E), Pushkar Lake, Ajmer (6º 4 45N; 74º 8E). Habits and habitat: It is a mud dwelling subspecies and preferred habitats are shallow muddy ponds, lakes and marshes. It is strongly carnivorous and lives entirely on fishes, frogs, snails and shrimps. Trionyx gangeticus Cuvier Localities in Aravalli foothills: Rajsamand Lake (4º 55 7N.; 7º 5 8E), Pushkar, Ajmer (6º 4 45N,; 74º 8E.), 8-- Pichola Lake, Udaipur (4º 7 46N.; 7º 5 5E), Udaisagar, Udaipur (4º 7 46N; 7º 5 5E), Habits and habitat: Strongly aquatic turtle; omnivorous and the diet includes a large menu comprising wide range of aquatic vegetation and 586

3 animals like fish, molluscs, frogs and crustaceans, it is also a carrion feeder and serves as very prominent scavenger. Breeding starts in late September and extends up to first week of November; the eggs are hard shelled with a average diameter of mm. and are laid at sand banks of river and other water bodies. Relative abundance and diversity of testudines in Aravalli foothills of Rajasthan The testudine were observed by naked eyes and with the help of field binoculars. At certain occasions the animals were caught and released after identification and desired study.. Relative abundance of Testudines in Aravalli Foothills From Aravalli foothills total 6 species of testudines were reported during the survey of -4. Out of 6 species of Testudine 4 species form the first records from the area. In testudines maximum number was of Flap-shelled turtle, Lissemys punctata punctata. Fresh water tortoise Geoclemys hamiltoni has been reported on the basis of individuals. Number of observed or collected individuals and abundence of different species of testudines, are depicted in Table-. Table- Percentage of Dominance of Testudines in Aravalli foothills of Rajasthan Family/Species Fam. Testudinidae. Geochelone elegans (Schoepff) Fam: Emydidae. * Geoclemys hamiltoni (Gray). * Kachuga tantoria circumdata (Mertens) Fam. Trionychidae 4. Lissemys punctata punctata (Lacepede) 5. * Trionyx gangeticus (Cuvier) 6. * Hardella thurgi (Gray) of observed/ collected individuals Abundance (%) * Sp. reported first time from the Aravalli foothills.. Species richness and abundance of Testudines Only one species namely star tortoise Geochelone elegans represent the family Testudinidae in the western side of Aravalli foothills, Bar Ka Ghata and its surroundings which is the most preferable habitat for the species. Maximum number of examples of this species could be observed from this area during our survey (fig- ) Testudinidae Emydidae Family Trinochidae Figure. Species richness and abundance in Testudines A. On the basis of availability of the food In Aravalli foothills maximum species of testudines consume the plant material. The 9 individuals of Geochelone elegans were observed while feeding on leaves and grasses of wild lilly and onion plants. We observed it feeding on the fruits of aquatic plants. Another species Hardella thurgi is exclusively aquatic and feeds on fruits and vegetables. The third species is Kachuga tentoria circumdata is also strictly herbivorous. Whereas the maximum abundance of carnivorous turtles was indicated by Geoclemys hamiltoni and Lissemys punctata punctata ( fig- ) Herbivorous carnivorous omnivorous Food habits Figure. Species richness and abundance in Testudines in food habits

4 B. On the basis of different Habitats Maximum species were observed in stagnant water bodies and muddy banks. It might be due to the availability of more food ie.,vegetation and small insects near water. In our observations we could notice the maximum number of individuals of Lissemys punctata punctata in water and the Geochelone elegans on land. The flap shelled turtles Lissemys punctata punctata were noticed in stagnant water bodies. The Geochelone elegans is a tortoise and is found in the terrestrial, vegetated, rocky terrain of the foothills. Rest all of the 5 types of habitats show approximately the equal richness of species and abundance (fig- ) Forest hill Rocky Bushy veg Fresh water Muddy bank Habitat Stagnant water Running water Figure. Species richness and abundance of Testudines in different habitats C. On the basis of different seasons The maximum species richness of testudines was observed in the monsoon season, which provides a most favourable and pleasant atmosphere to them in Aravalli foothills. Vegetation comes to their full bloom and provides abundant food to tortoise Geochelone elegans that feeds mainly on grass, vegetables, fruits and other plant material. For other turtles also the monsoon period is the most suitable as plenty of water is available in their habitats (fig- 4) encouraging more fishes as food.. Diversity of testudines and lizards in Aravalli Foothills of Rajasthan Diversity of testudines inhabiting this region and was estimated, the status of the species, reasons of their diversification and factors affecting their abundance. The data collected during the field study were analyzed by Handerson.. Shanon diversity index (H) has been employed. H = - pi log pi Where pi = the proportional abundance of the i th species.. Simpson s index D = (ni (ni-)/ N (N-) Where ni = the number of individuals in the i th species and N = the total no. of individuals Summer Monsoon Winter seasons Figure 4. Species richness and abundance of Testudines in different seasons To compare the diversity of testudine with different aspects, two commonly used diversity indices Shanon weiner (H ) and Simpson s yull were used. Simpson s index (D) measures the diversity of related aspect. With this index, represents infinite diversity and, no diversity or in other words we can say that low value of (D) represents the high diversity and high value of (D) represents the low diversity. The similar results are confirmed by Shanon diversity index which is totally inverse to Simpson index so the low value of (H) shows the low diversity and the higher value shows for high diversity. Either of these two indices can be used to check the data, but in present study both of the indices were used one is simpson (d) is disucused in text and shanon (H) is shown by graphical presentation. Which is near to the good population. Similar results were shown by Shanon index of diversity. A. Family wise In Testudines family Testudinidae showed the minimum diversity (D=.) as compare to family Emydidae (D=.7) and Trionychidae (D=.). The Geochelone elegans is the only species of family Testudinidae observed in Aravalli foothills of Rajasthan, whereas rest two families consist of two and three species respectively in each and proved to 588

5 be more diverse in comparison of family Testudinidae (Table). Table- Diversity Indices of Testudines Family wise in Aravalli foothills of Rajasthan Or./Sub or./family Simpson Index (D) Shanon Index (H) I Or. Testudines Fam:. Testudinidae... Emydidae.7.5. Trionychidae.. B. Season wise Shanon Index (H') Forest hill Rocky Bushy veg Fresh water Muddy bank Habitats Stagnant water Running water Minimum species of testudines were observed in winter season (D=.) while in summer season, maximum species of testudines appeared (D=.4). The reason might be the high temperature and scratching heat in summer season. SImilar results were shown by Shanon index of diversity (Fig.5) (Table) Monsoon Winter Summer Seasons Figure 5. Shanon index season wise in testudines Shanon (H) Table- Diversity Indices of Testudines in different seasons in Aravalli foothills of Rajasthan Simpson Shanon Index season Index (D) Index (H). Monsoon.9.4. Winter... Summer.4.4 C. Habitat wise Testudines showed maximum appearance at muddy bank and stagnant water (D=.46 and.4 respectively), of all the five habitats (Forest hill, Rocky, Bushy vegetation, Fresh water and fresh water) showed less diversity as compare to muddy bank and stagnant water. The only Tortoise Geochelone elegans of family Testudinidae, was found on land and rest all the species were mostly observed in water. SImilar results were shown by Shanon index of diversity in. Fig. 6, (Table4). Figure 6. Shanon index Habitat wise in testudines Table-4 Diversity indices of Testudines in different habitats in Aravalli foothills of Rajasthan Simpson Shanon Habitat Index (D) Index (H). Forest hill... Rocky... Bushy vegetation.. 4. Fresh water.. 5. Muddy bank Stagnant water Running water.. D. In different food habits Out of six species, only four species ie., Hardella thurgi,kachuga tentoria circumdata, Geochelone elegans and Trionyx gangeticus consume the plant products and are herbivorous whearas Geoclemys hemiltoni and Lissemys puncatata punctata consume small fishes and snails and are carnivorous. Only Trinoyx gangeticus is omnivorous species. Similar results were shown by Shanon index of diversity in Text. Fig. 7, (Table5). Shanon Index (H') Herbi car omni Habitats Figure 7. Shanon index food habit wise in testudines 589

6 Table-5 Diversity indices of Testudines in different food habits in Aravalli foothills of Rajasthan Simpson Shanon Food habits Index (D) Index (H). Herbivorous.64.5 (Grass, flower, vegetable, fruites). Carnivorus.9.4 (snails, frogs, fish). Omnivorous. ACKNOWLEDGEMENTS I am thankful to Dr. Anantkrishna, Director in Charge, Zoological Survey of India, Kolkata for providing all the facilities rendered in connection with this work. I thank Dr. Padma Bohra, Officer in Charge, DRS, ZSI, Jodhpur for all the help provided for the work. I greatly acknowledge Dr. N.Rathore Retd. Joint, DRS, ZSI, Jodhpur, for all the help and guidance. I feel my heart felt gratitude towards Late Dr. R.C.Sharma Scientist-E, Desert Regional Station, Zoological Survey of India, Jodhpur for guidance, encouragement, during this work. I am thankful to Dr. B.P.Singh Scientist-F, Department of Science and technology, New Delhi for financial support. REFERENCES Campbell, H.W. and Christman, P. 98. Herpetological communities wild report, US Department of the interior and Fish wild life service.d.c: 9-. Corn, P. and R.B. Bury 99. Terrestrial Amphibians, US Department of Agriculture forest service. General Technical Report GTR- 56. Henderson, P.A.. Practical methods in Ecology. Blackwell publishing Company USA. Minton, A A contribution to the herpetology of West Pakistan. Bull Amer. Mus. Nat. Hist. New York, 4(): Sharma, R.C.. The Fauna of India and the adjacent countries Reptilia (Testudines and Crocodilians) I: -96 pp. (Published Director, Z.I., Kolkata. Sharma, R.C Herpetology of the Thar Desert In: Faunal diversity in the Thar Desert: Gaps in Research. Ed. by A.K. Ghosh, Q.H. Baqri and I. Prakash Scientific Publisher, Jodhpur. Smith, M.A. 95. The Fauna of British India including ceylon and Burma, Reptilia and Amphibia- Loricata, Testudines. Taylor and francis, : XXViii + 85 pp., Londens. Tikader, B. K. and Sharma, R.C. 99. Handbook : Indian Lizards, Zoological survey of India, Calcutta :