KFRI Research Report No. 247 ISSN 0970-8103 STUDIES ON THE BIODIVERSITY OF NEW AMARAMBALAM RESERVED FORESTS OF NILGIRI BIOSPHERE RESERVE J.K. Sharma K.K.N. Nair George Mathew K.K. Ramachandran E.A. Jayson K. Mohanadas U.N. Nandakumar P. Vijayakumaran Nair Kerala Forest Research Institute Peechi - 680 653, Thrissur, Kerala State November 2002 KFRI Research Report No. 247 ISSN 0970-8103 STUDIES ON THE BIODIVERSITY OF NEW AMARAMBALAM RESERVED FORESTS OF NILGIRI BIOSPHERE RESERVE Final report of the project KFRI 276/97 Sponsored by Ministry of Environment and Forests Govt. of India, New Delhi J.K. Sharma, Director K.K.N. Nair, Scientist, Botany Division George Mathew, Scientist, Entomology Division K.K. Ramachandran, Scientist, Wildlife Biology Division E.A. Jayson, Scientist, Wildlife Biology Division K. Mohanadas, Scientist, Entomology Division U.N. Nandakumar, Scientist, Silviculture Division P. Vijayakumaran Nair, Scientist, FIS Unit Kerala Forest Research Institute Peechi - 680 653, Thrissur, Kerala State November 2002 Contents Summary Acknowledgements Chapter 1. General introduction - - - - - 1 1.1. Study area - - - - - 4 1.2. Historical background - - - - - 5 1.3. Environment and biodiversity - - - - 6 1.4. Objectives - - - - - 12 1.5. Presentation of results - - - - - 13 Chapter 2. Vegetation and floristic diversity - - - - 15 2.1. Introduction - - - - - 15 2.2. Review of literature - - - - - 15 2.3. Materials and methods - - - - - 17 2.4. Results - - - - - 20 2.4.1. Vegetation diversity - - - - 21 2.4.2. Floristic inventory - - - - - 32 2.4.3. Floristic diversity - - - - - 37 2.4.4. Discussion - - - - - 58 Chapter 3. Insect diversity - - - - - 105 3.1. Introduction - - - - - 105 3.2. Review of literature - - - - - 106 3.3. Materials and methods - - - - - 108 3.4. Results - - - - - 112 3.4.1. Insect fauna - - - - - 112 3.4.2. Insect community - - - - - 116 3.4.3. Major insect groups - - - - - 120 3.4.4. Insect-plant relationships - - - - 124 3.4.5. Discussion - - - - - 125 Chapter 4. Avian diversity - - - - - 140 4.1. Introduction - - - - - 140 4.2. Review of literature - - - - - 140 4.3. Methods - - - - - 141 4.4. Results - - - - - 145 4.4.1. Species composition of avifauna - - - 145 4.4.2. Abundance and density - - - - 150 4.4.3. Diversity indices - - - - - 152 4.4.4. Seasonal fluctuations - - - - 157 4.4.5. Density - - - - - 159 4.4.6. Discussion - - - - - 160 Chapter 5. Mammalian diversity - - - - - 164 5.1. Introduction - - - - - 164 5.2. Methodology - - - - - 164 5.3. Results - - - - - 164 5.3.1. Arboreal mammals - - - - 167 5.3.2. Herbivores - - - - - 171 5.3.3. Other mammals - - - - - 173 5.3.4. Carnivores - - - - - 173 5.3.5. Discussion - - - - - 173 5.4. Conclusions - - - - - 177 Chapter 6. Integration using GIS techniques - - - - 185 6.1. Introduction - - - - - 185 6.2. Materials and methods - - - - - 185 6.3. Results and discussion - - - - - 188 6.3.1. Baseline maps - - - - - 188 6.3.2. Spatial depiction of sampling pattern - - 188 6.3.3. Spatial integration of data on individual components 188 6.3.4. Spatial integration of available data on total biodiversity 188 6.3.5. Spatial depiction of other biodiversity parameters - 192 Chapter 7. Synthesis and conclusions - - - - - 195 7.1. The physical environment - - - - - 195 7.2. Biodiversity zones of New Amarambalam - - - 196 7.3. Management implications - - - - - 218 7.4. Further research needs - - - - - 219 References - - - - - 221 Summary New Amarambalam reserved forest, a part of the Nilgiri Biosphere Reserve, covers an area of 265.72 km2. The reserve is the abode of all the seven hill forest types of southern India, namely tropical moist deciduous, tropical semievergreen, tropical evergreen, subtropical hill forests, subtropical savannahs, montane wet temperate forests and montane wet temperate grasslands, apart from teak plantations raised within the reserve, containing indigenous arborescent flora. Analyses of different forest types in the study area for floristic, insect, bird and mammalian diversity were accomplished by laying sample plots in different vegetation types during 1997 to 2000. Floristic analysis of the arborescent species represented in sample plots in different forest types and teak plantations resulted in the recording of 305 taxa, under 212 genera belonging to 73 families. All these taxa are enumerated family-wise with up-to-date nomenclature, diagnostic description and distribution pattern for each species, highlighting endemics among them. The most dominant family represented in the area is Euphorbiaceae (33 species), followed by Lauraceae (18 species) and Rubiaceae (17 species). The dominant genera in the area are Litsea (7 species), Elaeocarpus (5 species) and Symplocos, Diospyros, Cinnamomum and Dalbergia, each containing four species. Almost 32 per cent of the arborescent flora of the area is composed of endemic species of Peninsular India, and many of them are either restricted in their distribution to southern Western Ghats or the Western Ghats of Kerala. The study could also locate few taxa either reported in literature as endangered or extinct. Structural data generated on the arborescent flora of the area were analyzed vegetation- wise and the number of species represented in various plots in each forest type, number of individuals per hectare, basal area, diversity index, dominance index, richness index and evenness index were calculated. The diversity analysis showed that arborescent species of tropical semievergreen forests have highest diversity index (H’) value of 3.89, which is followed by subtropical hill forests (3.58), tropical evergreen forests (3.45), montane wet temperate forests (3.15) and tropical moist deciduous forests (3.07). The diversity value of the arborescent flora is the lowest (2.57) for subtropical savannahs. These values were also compared with identical forest types represented in other areas of Kerala, analyzed earlier. Such a comparison had shown that the flora of New Amarambalam is more diverse than all other areas so far studied in the State, except for Silent Valley, where the vegetation is more diverse than that of New Amarambalam. It is concluded that this floristically rich and comparatively less disturbed area should be more effectively protected as a unique part of the Nilgiri Biosphere Reserve. Altogether 860 species of insects were recorded during this study from New Amarambalam. Of these, 535 species belonging to 14 orders and 83 families were collected from representative sample plots laid out in different forest types at various altitudes in order to study the insect community parameters. Maximum number of insects and species were recorded from the semi-evergreen and evergreen forests. With regard to species diversity, the evergreen forest recorded the highest value (4.51) followed by semi evergreen (4.35), moist deciduous (4.21) and sub tropical hill forest (4.30). The montane sholas recorded the lowest value (3.48). The dominant insect groups, with regard to the number of individuals, were Lepidoptera (29.82%) and Coleoptera (20.47%) followed by Trichoptera, Diptera and Hymenoptera. Species richness and diversity of Lepidoptera was greatest in the evergreen forests, followed by semi evergreen, sub tropical, moist deciduous and shola forests. With regard to Coleoptera also, the trend was more or less the same except that the number of species recorded from the subtropical forest was less compared to that of the moist deciduous forest. The insect fauna also contained a high proportion of rare and endemic species. Among butterflies, of the 133 species recorded, 28 species were found to be of high conservation status being either endemic/protected species. The evergreen forest had the maximum number of endemic/protected species (20) followed by semi evergreen forest (15 spp.), moist deciduous forest (7 spp.), sub tropical hill forest (7 spp.) and montane shola forest (5 spp.). There were also a number of rare species having great aesthetic value like the cicadas Cryptotympana varicolor and Platypleura insignis; the stag beetle Odontolabis cuvera and the colourful saturnids Actias selene and Loepa sikkima. On the whole, the fauna of New Amarambalam reserve forest is rich, varied and containing a high proportion of rare and endemic forms having close similarity with the Malaysian elements. A total of 2293 birds were seen and altogether 100 taxa of birds were recorded from the whole region. Nilgiri House Swallow (Hirundo tahitica domicola), Bluewinged Parakeet (Psittacula columboides), and Yellowbrowed Bulbul (Hypsipetes indicus) were the most common and dominant species in the evergreen forest where as Roseringed Parakeet (Psittacula krameri), Jungle Myna (Acridotheres fuscus), and Common Babbler (Turdoides caudatus) were the most common and the dominant species in the moist deciduous forest. Species richness was highest in winter months and lowest in May and June. Highest number of birds was recorded in January, February and March. Shannon-Weiner diversity Index showed high value (3.73) which is comparable with other tropical forests of the Western Ghats. Slightly higher bird diversity was recorded in the moist deciduous forests (3.70) than the evergreen forests (3.15). Species richness indices were also higher in moist deciduous forests (R1=11.23) than the evergreen forest (R1=9.88). Highest density of birds was recorded in the moist deciduous forests (775 birds/km2), followed by Shola (402 birds/km2) and the evergreen forests (400 birds/km2). Only 10 migratory species were confirmed