A recent research study by an Indo-Russian team has discovered that compared with 200-odd Amur tigers in Russian Far East, the Bengal tigers in three tiger reserves in India– Bandhavgarh, Kanha, Sariska– are about 20% further stressed. The stress degree was gauged by examining the glucocorticoids metabolites existing in the faeces of tigers.
” Increased stress and anxiety level for long term durations will impact the immunity and also health and fitness of big cats. Much more importantly, elevated stress and anxiety negatively affects reproductive hormonal agents which can result in decreased fertility and reproductive failure. We have earlier found captive elephants showing compromised reproductive cycle due to stress and anxiety,” stated Dr. Govindhaswamy Umapathy from the Laboratory for the Conservation of Endangered Species (LaCONES) at the Centre for Cellular and Molecular Biology (CSIR-CCMB), co-author of a paper published in the journal PLOS ONE.
Tigers in the Kanha reserve had the greatest faecal glucocorticoids metabolites level (indicators for stress and anxiety) while tigers in the Bandhavgarh reserve had the lowest degree and also equivalent with the Amur tigers of Russia.
” Though there is a variant in the collection of glucocorticoids metabolites in tigers in the 3 reserves, there is no considerable difference in the stress and anxiety levels. The raised stress and anxiety in Bengal tigers may be as a result of anthropogenic disturbance,” claims Vinod Kumar, Technical Officer at CCMB and also a co-author of the report.
Increased Population Density in India
While the tiger in India are smaller than in Russia, the anthropogenic disruptions are really high in Indian tiger population.
Moreover, with high anthropogenic anxiety, tigers in the three reserves experience greater population density compared to Amur tigers in Russia. At 11.33 tigers per 100 sq km, the density of tigers is much higher in India compared with Ussuriisky in Russia (0.15 tigers per 100 sq. kilometres). “Anthropogenic disruptions, as well as higher density, can be triggering greater anxiety in Indian tigers,” Dr. Umapathy claims.
“A 2015 research by our team uncovered that tigers reestablished in Sariska experienced high stress and anxiety because of anthropogenic disturbances,” Dr. Umapathy states. Due to high vehicular movement, tigers in the Sariska reserve encounter herdsmen, citizens who go to the reserve for accumulating timber as well as animals grazing. Consequently, the recreating ability of Sariska tigers has diminished.
Unlike Sariska, the Panna tiger reserve faces less anthropogenic disturbances. Because of this, three of the five re-established tigresses in Panna reserve created numerous progenies efficiently in four years, while in Sariska a tigress can efficiently reproduce only after 4 years.
This study has important environmental effects on the tiger population in India.