Results Chapter 3 A

RESULTS CHAPTER 3 A RESULTS INTRODUCTION, IDENTIFICATION AND MORPHOMETRY 3A.1 VEGETATION IN THE STUDY AREA The trees found in the habitats occupied by the owl vary with geographical locality and distribution range. In the study area, which is located on the Deccan plateau, I recorded following scrub vegetation in the areas occupied by the owl: Acacia nilotica, A. polyacantha, A. catechu, A. chundra, A. auriculiformes, A. tomentosa, Ziziphus sp., Holoptelea integrifolia, Artocarpus heterophyllus, Phyllanthus emblica and P. distichus, Bombax ceiba, Sterculia urens, Ailanthus excelsa, etc. Cropland is often interspersed with Azadirachta indica, Syzygium cumini, Mangifera indica, Tamarindus indica, Annona squamosa, A. reticulata, Achras sapota, Eucalyptus sp., Michelia champaca, Grewia tiliifolia, Aegel marmelos, Feronia elephantum, Melia azederach, Sapindus laurifolius. Cassia sp., Dalbergia latifolia, Memecylon umbellatum, Lagerstroemia sp. Millingtonia hortensis, Tectona grandis, Santalum album, Jatropha curcas, Bambusa arundinaceae, Dendrocalamus strictus, Asclepiadaceae sp. On coastal areas, Anacardium occidentale, Garcinia indica, Albizia lebbeck, Artocarpus heterophyllus, Cassurina litorea, Borassus flabellifer, Caryota sp. Pandanus tectorius, Cocos sp. etc. were seen. In the Indian Eagle Owl's Deccan plateau habitat, the xerophilous grasslands are composed of grasses belonging to species of Eragrosits, Aristida, Heteropogon, Apluda, Chloris, etc. Owls were seen frequenting suitable habitats with mesophilous grasses like Andropogon, Digitaria. Pennisetum, Themeda, Pancium, Setaria and to some extent hygrophilus grasses like Arundo, Hygrorhyza, Saccharum, Erianthus and Phragmites sp. In coastal areas the Indian Eagle-Owl was rarely seen on hilly coastlines near littoral vegetation like Rhizophora, Sonneratia, Avicena, sp. where the trees are sparse. On the coasts it sheltered under Spinifex squamosus, a gregarious sand binding grass or on Casuarina equisetifolia trees. In a large expanse of grassy plains with few low hills and devoid of tall trees, the Indian Eagle-Owl often perched on ground concealed in tall grass under the shade of a short Acacia tree. (Plate 9). 3A.2 THE CROP PATTERN In the study area the crop of wheat {Triticum aestivum), rice (Oryza sativa), jowar (Sorghum vulgare), nachani (Eleusine coracana) was harvested in late March or early April and rodents gleaned the scattered grain from the fields. The fields were again ploughed towards end of April for the next wet season and kept fallow till the first monsoon showers in June or July, when new seed was sown. So also, the crops such as green leafy vegetables, onion, groundnut, lentil, tomato, beans, green peas and horticultural products were cultivated. After this yield, one more yield of grain was obtained only in well irrigated areas. Acanthaceae, Asteraceae and Fabaceae shrubs appeared in favourable season and these were the hiding places for the owl. In summer, the much of the landscape became parched, barren and significantly devoid of Hfe forms. I saw that the resident Indian Eagle Owl often inhabited places where at least some type of a permanent water source remained throughout the year where continuous supply of food was assured. 3A.3 THE CLIMATE The average annual precipitation in the study area is derived from the SW monsoon, and it ranged from 250 - 1250 mm in the study area on the Deccan plateau and 1500 - 3500 mm in the study area on the coastal region. The temperature ranged between 6° C and 40" C during winter and summer respectively. Three well-defined seasons were 33 experienced in the habitats occupied by the Indian Eagle Owl. These are monsoon or the rainy season, winter and summer. 1. Monsoon: In the study area, during the monsoon (June to September), the arid terrain occupied by this owl become green and puddles, ponds and streams appear temporarily. The dry nullahs, streams, rivulets, water tanks and other perennial water bodies received their share of water. The green cover remained from mid June and the habitat resumed the parched yellow brown colour by late September. Then the black soil in cropland and in dry water bodies got fissured and several holes and burrows of rodents become visible and get exposed. The sand banks, gravel beds, stones, pebbles and Indians in riverbeds were exposed and became hot at noon. The average rainfall in coastal region, during the study period was normal. However, during 2005-06 and 2006-07 the study area in Pune and Solapur districts experienced a drought. 2. Winter: In the study area I observed that during early winter, respite from hot October temperature is obtained at night when activity of rodents and geckos is striking in this terrain. In mid winter, mornings were foggy. An occasional water hole remained filled and was surrounded by a thin rim of wooded area and it is in this cover that the owl was encountered. By October, the green grass in the open countryside became yellow. 3. Summer: In summer, from March onwards, the grass became prickly with thousands of thin loose clumps of filamentous darts with a reverse spike near the pointed end. They readily attached themselves to anyone who passed through the grass, a vegetative instrument for seed dispersal. The grassland became temporarily hostile to access due to this awn. Later, large areas of grassy pastures became denuded due to cutting or grazing by domestic cattle and sheep. The land became hardened and 34 the hot winds that blew at noon, collected surface dust and grit, and assumed the form of anticyclones or dust storms, depending on local temperatures and topography. 3A.4 A. THE GEOLOGY Laterite soil, mountain soil, red and black soils, gray and brown soils, sub-montane soil, desert soil and alluvial soils are seen in the various habitats in the distribution of the Indian Eagle Owl. Sedimentary rocks are seen towards north, igneous rocks in the Deccan and metamorphic rocks are seen in the southern part of its distribution. The Narmada-Tapi trough is sandwiched by the Deccan lavas, which in turn are encompassed by the Peninsular block with interspersed Gondwana trough in the regions occupied by this owl (Alfred et al, 2001). 3A.4 B. BIOGEOGRAPHIC ZONE AND AGROCLIMATIC ZONE The bio-geographic zones in the study area are the 'Deccan Plateau' in Pune and Solapur districts and the 'West Coast' in the Raigad and Ratnagiri districts (Roger and Panwar, 1988), while the agro-chmatic regions are 'Western Plateau and Hills Region' and 'West Coast Plains and Hills Region' respectively (Ghosh 1991). 3A.5 NEST CENSUS AND SPACING Mean distance between neighboring territories as calculated by the NND method was 3.28 km (0.9 - 6.47 km, sd = 1.45, n = 34). I found that the nests were uniformly dispersed in the region (G-tQst = 0.68). The closest distance between two nests of the breeding Indian Eagle Owls in adjacent territories recorded by me was 110 m where the nests of two pairs in adjacent territories were at the extreme but approximated ends of their respective home ranges. I saw that more than one home range often converged on one water source in arid habitats and hence such nests were close to one another. The several nests of a single pair within one territory were sometimes close, separated by only one meter, ans they were at times as flirther apart as 500 m. 3^ 3A.6 HABITAT CHARCTERIZATION AROUND NEST SITES 3A.6 A. Habitat types around nest sites 44 active nest sites were identified in the study area. Agricultural land, scrubland, grassland, water body, hilly areas, and human habitation were the six habitat types around the 44 nest sites in the study area. These habitats were characterized in a 1000 m circle around each nest by 'Look-Down Method' of visual survey as described earlier. Relative percent of each habitat around each nest site was recorded (Table 4). (Plate 10). 3A.6 B. Percent distribution of habitat types around nest site In the analysis of the various habitat types in the 1000 m radius centered at the nest, I found that agricultural land was the predominant habitat (Av. 30.9+17.4%, 10-75%), followed by grassland (Av. 21.9±18.5%, 0-60%), scrubland (Av. 15.0±8%, 5-40%), human habitation (Av. 14.0±7.4%, 0-40%), hilly area (Av. 9.6±5.5%, 0-25%) and water body (Av. =7.6+6%, 0-20%). All the nest sites were located either in hilly areas on cUffs or near water bodies in earth cuttings, while open habitats like agricultural land, scrubland and grassland were used as foraging areas. The observations are presented in a tabular form in Table 4. 3A.7 IDENTIFICATION OF INDIAN EAGLE OWL 3A.7 A. Description: (Plate 7). The Indian Eagle Owl is a large owl, dark brown in colour, with prominent streaking and mottling on plumage and the jizz with a vertical stout body and erect horns on the crown. I have recorded the following features of this owl through the spotting scope. Above, head and neck are tawny, yellow and appear bright in good Ught. Facial disc is whitish, eyebrows black and ruff dark brown and edged with fulvous. Large forwardly directed eyes with orange-yellow iris gives the bird a feline look. The iris appears 36 bright yellow in sunlight and orange in flashlight. Pupils are black and appear bright red or maroon in flash photography depending on the angle of the flash source. Forehead is dark brown to black with thin pale markings, becoming bright in breeding plumage. The aigrettes or horns are dark brown in front with fulvous edge and pale behind. Feathers have long, wide streaks of deep brown. Rest of the body plumage is rich brown with mottled and barred pattern of fLilvous colour on back and whitish wash on wing coverts and tertiary feathers. Quills are deep tawny, brown barred and dusky at tips.

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