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Feb 2��p I Journal ojChemoand Biosphere, Issue 1: VoL 1, pp. 90-98 Key tiger habitats in the Garo Hills of Meghalaya Ashish Kumae and Marcot B. G. 2 lAshish Kumar, JalaSRI Watershed Surveiliance and Research Institute, KCE Society's Moolji Jaitha College, Jilha Peth, Jalgaon - 425 001, Maharashtra,India, [email protected] 2Bruce G. Marcot, USDAForest Service, PacificNorthwest Research Station, 620 S. W. Main Street, Portland, OR 97205, U.S.A., [email protected] Abstract We describe assumed tiger habitat characteristics andattempt to identifY potential tiger habitats in the Garo Hills region of Megha\aya, North East India. Conserving large forest tracts and protected wildlife habitats provides an opportunity for restoring populations of wide-ranging wildlife such as tigers and elepha.TJts. Basedon limited fieldobservations coupled with focused group discussion with local villagers andsenior staffmembers of the wildlife wing ofthe State Forest Departmentof Megahlaya,we identified 20 localities in South GaroHills, which if protected andmanaged for tiger conservation, could help restore this fast disappearing species. An integrated multidisciplinary landscape scale approach to wildlife management, including designation of intact forest corridors among protected areas and reserved forests, would greatlycontribute to conservation of tigers andoverall biodiversity of this region. Keywords: tiger, population viability, landscape approach, conservation, corridors, core habitats Introduction Although the disappearance of tigers from The first ever scientific census of tiger some parks and reserves may be due, in part, to (Pantheratigris tigris) populations by the National poaching and other anthropogenic stressors, it is Tiger Conservation Authority (New Delhi) and still vital to defineand provide for their basic needs Wildlife Institute ofIndia (Dehradun) during 2007 for habitat and prey. Tigers -- iike many other revealed the presence of only 1,411 tigers in India wide-ranging carnivores and predators -- do not (Anop_ 2009a). Inrecent years, extirpation onocal have any one set of conditions of vegetation type tiger populations from several places including and structure, la.'ld cover, and topography that Sariska Tiger Reserve and Panna National Park is define their "habitat." Tigers in India and south one of the most urgent conservation issues of Asia have occupied a very wide array of national concern in India. Poaching seems to be environments, from Sundarbansto thornwoodland the major reason, but we should not overlook other of Panna National Park to Tropical Moist ecological factors playing key roles in the process Evergreen Forests in GaroHills. Even one Cfu, find ofloca! extirpation, or conservation,of the species. fresh tiger tracks in agricultural fields adjacent to Other factors might include loss of core tiger Corbett National Park, banana crops around Yaval habitats from increasing encroachment, forest Wildlife Sanctuaryin Jalgaon district, andon open fragmentation, and isolation. Many such factors islands in the Brfu1.maputra River of Kaziranga can determine the survival chances of National Park. "Tiger habitat" is highly variable, comparatively smaller populations within the and likely pertains to access to reliable prey (e.g., confmes of isolated habitats. 90 ============================== Journal o/Chernoand Biosphere, Issue 1: VoL 1, pp. 90-98 i Feb 2010 1 Why are small isolated populations at peril? It is well knownin population viabiiity theory population size (related to changes in aliele that, in general, small, isolated a..'1d temporally frequency)is only 33 individuals (using formulae variablepopulations may be subject to fargreater fromWaples 2002). Other measures of effective risk onocal extinction than are larger populations population size of 100 census adults, correcting connected to other populations in a for spatial structure, variable subpopulation metapopulation network (Fraterrigo et at. migration rates, intergenic drift, and 2003).Reasons include demographic variation, subpopulation extinction, vary from 50 to 99 environmental variation (including effects of individuals. Still other estimates can be environmental disturbance), and loss of genetic calculated correcting for variance in family size, I variability due to inbreeding, drift, and other sex ratio, and fluctuation in population size small-population effects. Extinction risk (Frankham et al. 2002). Each estimate of increases nonlinearly with small population size effective population size measures some due to a combination of many of these factors decrement to viability. Research is needed to (Liao andReed 2009). Starldardformulae canbe determine which factorsmost pertain to tigers in I • used to gauge potential degree of drift and MeghalayaandNor illEast India. inbreeding, and to calculate effective population In North EastChina, a combination of forest size which is often far smaller (half or less) than habitat disruption, decline or local extirpation of census or total population size (Waples 2002). native prey species, anddirect killing by hlh'1lans, Some factors affecting this in small populations are likely the main threats to Siberian tigers, include increased variationin birth rate, increased severely reducing or eliminating local variance in family size, decreased number of popUlations in the Wandashan, Laoiing, and subpopulations, loss of genetic variation within Mudanjiang MOlmtains. It remains as important demes with resulting decrease in viability of to briefly list the main unknowns and offspring (decline in fitness),and deviations from uncertainties as to tiger population viability in normal sex ratio. Also, the new fieldof landscape Meghalaya, as it is to list presumptions about prey, genetics is providing a means of evaluating the habitat use, numbers, and life history parameters. degree and cause of population isolation With few to no population, demography, and (Holderegger and Wagner 2006; Manei et al. ecology studies having been done in Maghalaya, 2003). there is likely much uncertainty about population For example,the inbreeding effective size of size, trend, habitat selection and prey selection, anisolated popUlation with a total census number although one could begin to pose assumptions and of 100 adults, 1 female bornper adult female,and hypotheses based on tiger studies conducted a variance of 2 offspringper adult female, is only elsewhere in India in similar environments (e.g., 49 individuals, and the variance effective southIndia). sambar, chital and other ungulates), water, good quantifynative forests of the region which seem to hiding cover, and at least some area remote from support tigers and that could be delineated as human habitation. The GaroHills areknown for potential core tiger habitats, and we suggest a few elephants, but this area also provides excellent conservation measures to protect this fast habitat for tigers. Until 2000, tigers were sighted in disappearingspecies. the forests of Balpakram and Baghmarain South Garo Hills (personal observation of authors). A StudyArea webpage at the official website of Goverrunent of The study area spanned 2459 km' and Meg,.1-jalaya,which was accessed on December 24, comprised South Garo Hills district and adjoining 2009, alsosuggests the existence of tigers in Garo Nokrek Biosphere Reserve a..'1d National Park· Hills(Anon. 2009b). In this paper, we describe and along with the surrounding community landin East 91 / Feb2010 1 JournaiojChemoand Biosphere, Issue 1: VoL l,pp. 90-98 and West Garo Hills districts (Fig. 1). This area during last two decades of twentieth century . belongs to biogeographiczone 9B, i.e., North East (Talukdar 2004). Forest fragmentation has - North East Hills, and falls within 90' 07'- 91" E resulted in the conversion of dense evergreen and longitude and 25' 02'- 25" 32' N latitude (Rodgers semi-evergreen forests to open deciduous forests. et at. 2000). These protected areas (PAs) include Conversion occurred mainly due to unplanned land BalpakramNational Park(BNP , 220 km\Nokrek uses, especially jhum (Kumar et at. 2002, 2008). National Park(NNP, 47.48 km', later extended to The remaining, largertracts of intact evergreen and 80 km2 anddeclared as a Biosphere Reserve), Siju semi-evergreen forest likely provide the best Wildlife Sanctuary (SWS, 5.18 km'), and habitat for wide-ranging wildlife species, Baghmara Pitcher PlantSanctuary (BPPS, 2.7 ha). especially tiger and elephant along with other Four reserved forests in the study area include carnivores and ungulates of the region. Our task Baghamara (BRF, 44.29 km\ Rewak (RRF, was to quantifY the degree of remaining forest 6.48km'), Emangiri (ERF, 8.29 km'),andAngratoli cover, fragmentation, and locations of existing intact native forest in Garo Hills for possible (ARF, 30.11 km') Reserved Forests (RFs). The consideration as additional PAs or as habitat PAs and RF s constitute only 15%of the study area, corridors to connect PAs for elephants, tigers, and with the remainder belonging to the local Garo other wildlife. community. In general, major threats to the large, wide Methods ranging wildlife of the study area and Meghalaya, We defined potential tiger habitat as tracts of including tigers andelephants, are from prevailing evergreen and semi-evergreen forest that are most land use and habitat-alteration practices, and intact, least fragmented, largest, and that could be increasing human encroachment. Most of the land connected with existing PAs and other such forest of the region