SAVING LARGE MAMMALS

Our large vertebrates like tigers, elephants, lion tailed macaques, king cobras, great hornbills, great Indian bustards are all flagship species of our bio-diversity.  They represent and indicate the quality of our natural landscapes.  These apex indicator species are like warning lamps that indicate how healthy natural landscapes continue to remain in the face of our onslaught.  Their survival is as useful to us as the oil-pressure lamp on the dashboard of a car or the battery life indicator on a laptop computer. 

Some forms of biodiversity (soil bacteria, fungi, crows, rats, jackals) can survive on intensively human dominated landscapes.  Other forms of biodiversity may need more natural landscapes to survive but can still withstand intensive disturbances (wild pigs, toddy cats).  But preserving viable populations, communities and landscapes of apex species is the key to saving critical eco-systems.

These large bodied indicator species need large tracts of well-protected habitats for their survival in terms of their diet and home ranges.  Their sheer size demands greater amounts and variety of food and these animals therefore need to traverse larger home ranges.  For example jackals are known to subsist right in the heart of Bangalore city feeding on smaller prey like rats, birds and also on garbage dumps.  But an adult elephant whose home range spreads over 26,500 ha (Desai 1991) will not survive even in small-protected forests, let alone Bangalore city. 

A carnivorous diet further accentuates this need for wide ranging behavior among large vertebrates.  To survive and reproduce, a single tiger may need a prey base of about 400 deer-sized animals (Karanth 1998) in a year.  A home range supporting such a prey base may extend to over 15 to 500 square kilometers, depending on prey density. 

Landscape species like elephants and tigers, therefore, live at relatively low densities.  To ensure survival and reproduction of these niche specialist species relatively extensive, undisturbed landscapes are needed.  Not all extinction-prone species are large, wide-ranging or carnivorous.  Many occupy narrowly defined ecological niches.  The lion tailed macaques and great hornbills of the Western Ghats have critical needs for food obtained from rainforest trees or lianas, and they shelter in old growth tall timber.  These niche specialist wildlife cannot shift their ranges elsewhere.  So, these landscape, flagship, large bodied species are ideal barometers to analyze the problems and success of ‘wildlife conservation’.