The tiger, an animal held so dearly in most of our hearts, is experiencing a dramatic decline in its numbers as well as its habitat. Although most conservation strategies, understandably, have been centered on increasing tiger population size, scientists have discovered recently that maximizing the connectivity between tiger populations in the protected areas of Central India might play a more crucial role in conserving tiger populations than increasing population size.
Using various statistical tests and a fancy-schmancy computer program called STRUCURE 2.3.2 to detect new migrants into a population, scientists found that there definitely is long-range dispersal (approximately 650 km) of the tigers between the populations in the Central Indian landscape (Aditya et al. 2013).
They also found that tiger connectivity is influenced by the presence of human settlements, roads, the density of the tigers in the host population, but surprisingly, not by the distance between protected areas (Aditya et al. 2013). This was achieved by seeing if there was a relationship between connectivity of the tiger populations and the presence of human settlements, roads, or other elements of the landscape (Aditya et al. 2013).
Now, you might be asking yourself, why are these results significant? Well, the answer lies in the fact that having a genetically diverse population is essential for sustaining a viable population, and movement between populations enhances this genetic diversity.
The more genetically diverse a population is, the higher the probability that the population will survive in the face of an event such as a natural catastrophe (hurricane, monsoon), the introduction of a new, nasty bacterial disease or virus, or any other terrible event that you could think of that could severely alter the tiger population size. The next question that comes to mind then is, what can we do to enhance the connectivity between these tiger populations?
The answer to this question lies in the formation and maintenance of habitat corridors. A habitat corridor is a wildlife area designed to allow individuals to move more easily between different populations, reducing the negative effects of inbreeding (you wouldn’t want Aunt Sally and Uncle Joe to be mating would you?) and increasing genetic variability.
Due to the findings that there is long distance movement between tigers in the protected areas, we know that meta- populations (the protected areas), with a decent amount of gene flow between them already exists. Now it is our job to maintain and enhance existing connectivity between tiger populations by focusing our efforts on the viability of the landscape and habitat between protected areas.
Within the next century most of the world will probably be urbanized, and India in particular has been showing a considerable increase in the appearance of new towns and urban centers over the last decade (Aditya et al. 2013). This development could potentially be harmful to the landscape connectivity between tiger populations.
In particular, there has been a proposal to expand a national highway on to the Kanha-Pencha corridor, a habitat corridor that has been proven to be extremely important in aiding the movement of tigers from population to population (Aditya et al. 2013).
Data on the importance of habitat corridors, such as presented in this paper, should be used by conservationists to try and advocate a stop to this development.
Additionally, conservation strategies heading into the future should focus on identifying areas that are crucial habitat corridors and providing earnings to communities based on the habitat corridors conserved by them.
By incorporating changes at the landscape level to protect and maintain habitat corridors, with the conservation strategies already set in place to increase tiger population size, the future should be very bright for our dearly-loved tiger population.
Aditya Joshi et al. “Connectivity of Tiger (Panthera tigris) Populations in the Human-Influenced Forest Mosaic of Central India.” Plos One. 8 (2013): n. pag. Web. 6 Nov 2013.