INTRODUCTION
During the last century, there were over 40,000 tigers in India. This number has dwindled to 1827 by 1972 due to poaching, illegal hunting, fragmentation and destruction of habitat, making them an endangered species. The Government of India started "Project Tiger" on April 1st, 1973 to protect the tigers from extinction. Uttara Kannada district was exceptionally rich in tigers almost until late 19th century. British chronicles show hundreds were hunted down in the district during late 19th century, and such hunting was even sponsored by the government. Presence of numerous tigers in the district until the close of 19th century highlights the richness of forests interspersed with grasslands, abundance of water resources and richness of wildlife in general, especially the grazing mammals, constituting the prey stock of the wild carnivores.
Dandeli Wildlife Sanctuary with the extent of 206.75 sq kms was first notified as Game Sanctuary in the year 1956 (vide Bombay Govt. Resolution WLP.1957 dated 10-05-1956). This was extended to 5729.07 sq kms (vide Government of Karnataka Notification No. AFD 52 FWL 74 dated 08-01-1975) and subsequently reduced to 834.157 sq kms (vide FFD 150 FWL 81 dated 01-09-1987) and 475.018 sq kms. (vide draft Notification no. FEE 172 FWL 93, on 29-04-1994), which was finally notified as Dandeli Wildlife Sanctuary (vide FEE 58 FWL 96/09-03-1998). The draft notification of Anshi National Park was done covering an area of 250 sq kms (vide AHFF 77 FWL 87 / 02-09-1987) and the final area notified is 339.866 sq kms (vide Notification No. FEE 221 FWL 99 dated 18.08.2003). Both the Protected Areas with the spatial extent of 814.884 sq km was declared as Tiger Reserve on 4th January 2007 (GO No. FEE 254 FWL 2006). This along with the Mahaveer Wildlife Sanctuary of Goa covers an area of over 2,000 sq.km.
Anshi-Dandeli Tiger Reserve-Study area
Figure 1.1: Dandeli-Anshi Tiger Reserve
The Anshi-Dandeli Tiger Reserve (ADTR) covers the hill ranges of northern Uttara Kannada district in the taluks of Joida and Haliyal (Figure 1.1). The western side of the Tiger Reserve, receive seasonal heavy rainfall from the South-West Monsoon to the tune of 3000-6000 mm. Tropical evergreen forest is the climax vegetation here. However, human factors through millennia have transformed bulk of these forests into semi-evergreen types, interspersed with savannas and agricultural areas. Progressive decline in rainfall towards the east, which gradually merges with the Deccan Plateau in the rain-shadow region, is responsible for moist and dry deciduous forests. Long history of forest burning in the past and wholesale transformations of the forests into teak plantations, beginning with the British period have acted as powerful factors that modified natural vegetation. Places such as Kumbarwada, Diggi, Terali, and Kundal have large expanse of grasslands, due to the slash and burn cultivation practices earlier by shifting cultivators consisting communities such as Kunbis and Kumri Marathis. Gavli pastoral tribes and Siddi forest dwellers live in this area. Many village settlements are present in the reserve and the surrounding areas where the wild animals move.
Faunal diversity of Anshi and Dandeli Tiger reserve
This Tiger- Reserve is habitat for large mammals, which include bonnet macaque, spotted deer, barking deer, mouse deer, gaur, civet, Malabar giant squirrel, pangolin and sloth bear. Besides, the black panther, elephants and tigers are rare species found in the park. Reptiles spotted in the park include the king cobra, krait, python, rat snake and viper. Around 200 species of birds are reported from the park. These include the adjutant stork, ashy woodswallow, black-crested bulbul, blue-headed pitta, brahminy kite, broad-billed roller, crested serpent eagle, and yellow-footed green pigeon (Source: Karnataka Forest Department, Dandeli).
IMPORTANCE OF GRASSLANDS FOR TIGER CONSERVATION
The tiger is internationally recognized as an endangered animal destined to be extinct in the wild if the forces causing its decline continue. Many small tiger populations are completely isolated and critically endangered. Entire subspecies from Bali, Java and areas adjacent to the Caspian Sea have not survived. The South China tiger is down to a few individuals and is slipping away. There has been much anxiety for the tiger and its future. Some predict the tiger’s demise, with some isolated populations expected to blink out in the near future (Seidensticker et al., 1999). The resonating theme of the excellent work Riding the Tiger, has been the importance of the tiger’s prey, mainly the large mammal. “…this great cat evolved as the predator of the largest deer, wild cattle and wild pig, and where this essential prey has been extirpated, the tiger does not survive. However, where large prey are abundant, the tiger survives and has a robust reproductive output” (Seidensticker et al., 1999).
If we examine the important prey animals throughout Asia, where the tiger survives in many pockets, there are many kinds of deer among them such as the chital, sambar, chousingha, muntjac etc. and other ungulates like gaur, wild pig, nilgai and domestic cattle; they sometimes even feed on langurs and porcupines. By and large the tiger’s prey are herbivores that depend substantially on grasslands. Yet we cannot underestimate other landscape elements such as forests, scrub, riverine habitats and even mangroves as harbouring tigers and their prey. Diverse kinds of landscape elements are preferred by tigers. Even their prey, deer for example, not only feed on grasses but also browse on the leaves of trees and fallen fruits of many trees. Water bodies are visited by almost all animals. Therefore the Tiger Reserve should be a healthy combination of different landscape elements, including the grasslands that provide bulk of the fodder needs of the ungulates.
UNDERSTANDING GRASSLANDS
Grasslands are the grass-dominated areas with few trees. Global grasslands even though widespread are shrinking alarmingly and merit consideration as one of the most endangered ecosystems, even more so than tropical rainforests. Though the grasses form an easily identifiable natural group of plants they have remarkable diversity. Grass belongs to family Poaceae, the fourth largest family of flowering plants, has over 700 genera and probably 10,000 species (Sreekumar and Nair, 1991). Civilizations flourished in and around grasslands as grasses meet most of the basic human needs - bulk of the food, fodder, thatching materials, medicines etc. Livestock constitutes the backbone of agricultural economy and its sustenance depends on the grasslands. In grasslands worldwide are found maximum numbers of large herbivore animals. They also hold the key to the richness of wildlife as most wild herbivores survive on grasslands. In the grassland ecosystems we find high levels of productivity and energy utilization. A forest cannot support such large populations of grazing animals since the herb layer is less luxuriant and deficient in grasses, and the forest shrubs and trees cannot withstand heavy browsing, nor are most of them palatable. In such situations, even the forest living animals come out into open grasslands and clearances for grazing. The rapid decline of natural grasslands is due to several reasons. Grasslands being relatively open areas with low-stature vegetation receiving higher light intensity, they are easily vulnerable to invasive species, more so following disturbance (Wagner, 1989). They are sensitive to various human impacts such as conversions to agriculture and rangelands, spread of invasive species introduced by humans, road making, alterations in natural fire cycles and pollution that alters soil fertility and rates of plant growth. Their structure and function make them one of the most vulnerable land ecosystems to global climate change (Schlesinger, 1997; Mooney and Hobbs, 2000; Lejeune and Seastedt, 2001). Grassland studies are of paramount importance and pre-requisite for conservation and management of wildlife (Panwar, 1986; Rodgers and Sawarkar, 1988 Rahmani, 1992). Many studies are found on grasslands of India, including of the Western Ghats (Lele et al., 1997; Bhat et al. 2005; Misra and Misra 1981; Kotwal and Pandey, 1981; Rawat et al. 1997; Lehmkuhl, 1989; Rodgers, 1990).
Evolution and spread of grasslands: Grasses appear in the fossil records of the Earth from the late Cretaceous Era about 100 million years ago. The early grasses probably evolved at high altitudes, above the tree line in the mountains, because all grasses have one common attribute; they cannot tolerate shady conditions. As dense forests covered most of the land surface the deep shade of the trees did not favour grasses underneath. Pollen of grass species is notable for its absence beneath all types of forests but as soon as tree pollen begins to decline, grass pollen makes a sudden appearance in the pollen profile. There is also the unexplainable fact that pollen from grasses has been observed at the same time in many different parts of the globe. This probably is correlated to increased aridity in climate unfavourable for forests (http://www.bcgrasslands.org/library/world.htm.).
Grasses and Adaptability: Although grasses do not thrive underneath the canopy of forests they belong to a vegetation type that actually thrives on being eaten, burnt, and trampled upon. They can grow at sites ranging from sea level up to the edges of high altitude glaciers and tolerate salinity, acidity and alkalinity. Many grow submerged partly or fully in water, yet others colonize deserts. They are successful invaders capable of colonizing diverse habitats due to their various adaptations. Their remarkable genetic adaptability equips them to adapt to such varied environmental conditions. By means of sexual reproduction they can quickly evolve new varieties to suite new growing environments. Perennial grasses spread fast by vegetative methods as well. Close to their nodes are tender spots packed with actively dividing cells constituting meristematic tissue. Stems elongate and new shoots sprout from these meristems (Misra, 1980; http://www.bcgrasslands.org/library/world.htm.).
Grasses of wetter conditions (Figure 1.2) are softer and delicate than land grasses. They have less of fibrous tissues in them. Their leaves are bright green, thinner and broader than land grasses. Hubbardia heptaneuron, a grass feared to have gone extinct from the spray zone of Jog water falls in Uttara Kannada is very delicate with almost translucent thin leaves and soft tissues. The grass has been rediscovered in some waterfall areas of Maharashtra Ghats. The plant parts of aquatic grasses are spongy due to air spaces that enable to them to keep their floating. However, because of silica crystal deposit even aquatic grasses like the rice plants can have rough and sharp leaves. Grasses of the other extreme, in water scarcity areas, have xerophytic adaptations. They look duller and many are with hairy surfaces. Some have water storage tissues in their leaves, which enable them to survive drought. These grasses are stronger with lot of fiber tissues. Most desert grasses have stomata on the upper epidermis which also has special cells that help in rolling of leaves into a hollow tube. Therefore the stomata are protected from the desiccating conditions during the hot hours of the day. Not only in deserts in most other drier habitats like sandy sea shores, rocky places, and other open dry areas, grasses tend to have similar adaptations.
Figure 1.2: Grasses and sedges (grass like plants) along with water-lilies
The trailing habit of many grasses (e.g., Cynodon dactylon, Oplismenus burmanii etc.) helps them to withstand grazing pressure, trampling and even fires. Taller grasses tend to dominate areas where they have to compete with dicot herbs. Bamboos though woody and tree like are also grasses. For them the height is of advantage in competing with trees of the forest. Grasses are prolific seed producers. Their smaller seeds have enabled them to spread widely. Most grasses also reproduce vegetatively, so that even if their shoots are browsed by animals or destroyed in fire, they produce fresh shoots from underground rhizomes or from nodes at ground level. Some grass species can survive in diverse ecological conditions; for instance the Bermuda grass (Cynodon dactylon), commonly found in Anshi- Dandeli Tiger Reserve can grow in submerged habitats as well as on drier soils. Tiny, wind dispersed seeds of many grasses and their light loving nature enable them to be the pioneer colonizers of freshly created open habitats. Elasticity of grass internodes confer on them survival value in windy conditions and resist trampling. Another reason for the success of grasses is wind pollination and their non dependence on animals as pollinators. All such characters of grasses provide them with greater plasticity to grow in situations not favorable for many other flowering plants.
Grasslands constitute a critical resource, as the grasses constitute bulk of the diet of herbivorous mammals, especially ungulates, which constitute bulk of the prey for the big cats, the tiger and the panther. Ecological history of the Western Ghats, especially of Uttara Kannada district, and the recent studies highlight that the number of tigers in any reserve is correlated to the number of prey animals and prey animals depends on grasslands. Therefore grasslands deserve prime attention in the management plans of ADTR. The work on grasses of ADTR is scanty and this work constitutes preliminary work which help in understanding grassland ecology. Tigers are part of a landscape of varied elements and grasslands cannot be treated in isolation, but in combination with forests, savanna, scrub, streams and rivers, gorges, ravines and cliff, which in a mosaic constitute homes for the deer, sambar, gaur and pig which are among the important preys of the tiger.
This report is based on a short term study conducted on the grasslands of ADTR keeping above objectives in view. Here we try to understand and place the grasslands of ADTR in the backdrop of the world of grasses. Not only large grasslands, but various microhabitats of grasses have bee identified and their characteristic flora catalogued. The results are discussed at length and many useful recommendations are arrived at with the tiger in the focus. Though apparently digressions from grasslands are many in this report, efforts are made to harmonise them into the holistic concern for conservation. We have also provided here locations of grasslands and other openings in the forest canopy based on Google Earth, and made efforts at estimating the forest Range-wise area under grasslands. This report carries a useful guide of pictures and descriptions of a good number of grasses of the Reserve. The use of technical terminology cannot be easily dispensed with while describing grasses, since they are plants with very subtle features. We have provided a glossary of technical terms used in taxonomic descriptions. This report is more of a preliminary study and constant efforts have to be carried out in the coming years to understand the dynamics of the grassy habitats, evaluating them in sustaining a good prey population critical for increasing the number of tigers to the potential carrying capacity of the Reserve.
