July 29, 2019 by Species Ecology
Science Bound Conservation is Required to bring Wild Tigers back from Near-Extinction-Crisis
Like all its felid cousins, tiger is graceful and awesome creature. It is in fact the largest carnivore in felid guild with its historical population range all the way from Turkey to Russia, Indonesia to Japan, and Iran to Thailand. Sadly, current population size is shrunk to mere 3% and tigers now live in handful of nations in South and South East Asia and Russian Far East. It is classed as endangered species with global population possibly range from 3500 to 3800 tigers that are now facing range of human persecution across tropical and semi tropical biomes. Historically, there were hundred thousands tiger but due to unbridled human population and economic growth and other associated causes, tiger numbers quickly plummeted to less than 4000 by the end of 20th century. Tigers now live in an isolated and fragmented patch mosaics surrounded by expanding human encroachments in the form of agricultural and cash crop mono culture expansions across Asia. In spite of the large scale global consensus to help safeguard the remaining wild tiger population over the past half a century and considerable investments on tiger conservation, wild tigers in their native ecosystems are far from secure footing. To help conserve the dwindling and remaining isolated population of tigers across its range nations, science bound conservation initiatives is more than an ecological imperative, it is an absolute priority.
In the year 2010, ambitious Global Tiger Recovery Program (GTRP) was initiated by bringing together governments of all tiger range nations and international conservation organizations in St. Petersburg, Russia. This was the most exciting, monumental and largest gathering of international ministerial in conservation conference that ever took place to help recover single endangered species in Asia. The core objective of the GTRP is to double the tiger numbers by year 2022 coinciding with the Chinese New Year referring to Chinese Year of the Tiger. Surely, the GTRP gained enormous momentum both politically and socially and garnered significant recognitions from international conservation groups and forums. Even high profile Hollywood celebrities like Harrison Ford got involve and gave powerful speech at St. Petersburg. The declaration was made and signed by all tiger states which became St. Petersburg Declaration to help safeguard and double the remaining tiger population in the wild. Nine years has gone past since the inception of GTRP and St. Petersburg declaration, yet tigers long term future security is far from reality. One can make an argument that it is all elite and posh to held high profile international conference followed by submission of glossy and chick posters and publications focusing the plight of tigers, but in reality, the tiger numbers continue to decline in dramatic fashion with little over 100 tigers get killed per year across tiger range nations. Therefore, ‘Paper Tiger’ hardly managed to escape from the conference room and Ivory towers thereby failed to became healthy live tiger with secure future in the wild.
Lack of science bound study of tigers and under implementation of ecological science in national conservation policy framework may one of many reasons, tiger range nations are facing serious challenges to stabilize or increase tiger population size. Despite the fact, doubling the tiger numbers is a collective goal and does not translate to individual national goal, all tiger states have agreed to stabilize and make an endeavor to increase tiger population size via St. Petersburg Declaration. This unfortunately has not been achieved in most of the tiger nations except India and Nepal where dedicated and ecologically valid conservation action plans have been undertaken with marked positive outcome. Even in India, which holds over half of the tiger population and which still has millions of square kilometers of suitable tiger habitats, most of the forest are in fact empty forests. It is therefore not surprising that despite over 1.5 million square kilometers of tiger ecosystems exist in South and South East Asia, over 75% of the tigers are in fact living in less than 5% of the areas and under increasing anthropogenic pressures in the form of habitat fragmentation, agricultural expansion, tigers’ essential prey depletion and human encroachment. Doubling the tiger numbers by year 2022 is surely an ambitious goal but to make this goal a reality, standalone political will or emotional plea to save tigers is not good enough. Identifying key conservation areas within the broad heterogeneous patch mosaics of tiger conservation landscape (also known as TCL) is one of many objectives that require dedicated science bound conservation action plan. Considering to the fact that tigers now live in highly insularized and patchy habitat and facing human induced perturbations of all forms, identifying ecologically suitable habitats for tigers where breeding population size stands better chance for long term survival can help reach the target towards doubling tiger population size. In the contrary, where tiger numbers become too small or breeding females are absent, conservation actions and investment in those habitats may pose little significance to increase population size. Other important focus should be interconnecting those breeding areas with nearby forested ecosystems for young tigers to disperse and populate from its source population. This comes under creating source-sink structure and to manage the isolated and fragmented population size within meta-population form within the broad tiger conservation landscape.
In spite of the fact, scientific study of tigers actually begun in early 1960s by brilliant American wildlife biologist George Schaller and his pioneering work on tigers in Kanha National Park in India was first published in the form of seminal book called ‘The Deer and the Tiger’ in 1967, most of the scientific works on tigers still remain unnoticed by government officials working or in charge of conservation planning and implementation in tiger range nations. Major ecological advances were made by another American carnivore ecologist Melvil Sunquist in the early and mid 70s through radio-telemetry study in Chitwan National Park in Nepal to understand tiger population distribution, its hunting and feeding habit, its reproductive behavior and home range size and other ecological vital information. In the early 90s, Indian wildlife biologist Ullas Karanth and James Nichols (American Wildlife Scientist) pioneered the scientific study of tigers under modern ecological and statistical framework to accurately estimate tiger population size and density by utilizing the power of camera trap capture-recapture modeling method in Southern states of India. Following Karanth’s footsteps wildlife biologists Kae Kawanishi and Monirul Khan reliably estimate the tiger density for the first time in Malaysia and Bangladesh in early this century. We now have wealth of ecologically valid data on tigers: thanks to these pioneering biologists and their associates but ironically it did not help prevent chronic and dramatic decline of tiger numbers across tropical belts. Forty years or more have gone past and tiger conservation certainly entered into the realm of cutting edge statistically valid and ecologically sound modern research framework, yet reaching the target to double the tiger population remain far from reality.
Armed with forty-years of scientific study of tigers, modern wildlife biologists and conservation ecologists alike from tiger range and non tiger range countries mainly from North America and Western Europe, are jointly collaborating whenever and wherever the opportunity exist to strengthen and build science based ecological conservation of tigers in Asia. Advancements in India and Nepal over the last forty years to help save tigers enabled surrounding nations like Bhutan, Bangladesh and Myanmar to embrace scientific study to understand tiger population and ecology . These nations have made attempt to understand tigers’ demographic parameters within ecologically and statistically valid norm for the past ten years or so. For example, for quarter of century or more, Bangladesh conducted ad hoc study to estimate tiger population by using non scientific methods of several kinds. However, this has now all changed and recent studies were all driven by solid science of ecology, statistics and mathematical modeling. Reliable estimation of tigers in Bangladesh now reveals that tiger population size is in fact four times lower than what was estimated through ad hoc studies over many decades.
These latest studies provided us not only with good sets of quality data on demographic parameters and distribution patterns of tiger over spatial and temporal scales covering hundred and thousands of tiger conservation landscape but also revealed great deal of ecological information about tigers that in the past were simply absent. For example, Sunquist and Karanth’s work revealed tigers’ hunting efficiency is by and large 10%. In the surface it may mean little but when put into ecological and conservation perspectives, the percentage can enable wildlife biologists to answer critical ecological questions. Adult individual male tiger require between 2500 kg to 3000 kg of meat per year. Breeding female raising litter of 4-5 cubs needs considerably more meat on the hoof and works out roughly 3500 kg per year. Majority of the tiger habitats are increasingly becoming empty forest where tigers’ prey base remain scarce. On the other hand millions of years of evolution have made tiger as one of the most top-notch landscape species on earth in which it is designed to hunt down large ungulates (hoofed mammals) weigh between 50kg to 1000kg depending on the landscape where these preys and tiger inhabit. To take tigers hunting efficiency into account, if an ecosystem is blessed with 500 healthy deers weighing on average 50kg per individual, an individual adult tiger would then able to hunt down 50 of them per year hence barely meeting the annual energy nutrition budget. Conservation implication of tiger’s hunting efficiency then simply translates to effective management of prey population. In fact, prey population is the critical determinant of long term tiger population viability. Classic landscape predator sitting at the top of the food chain and governing the ecosystem as if prime minister of the nation, cannot be survived, reproduced and repopulated without adequate, regular and healthy supply of nutrients and proteins. Just like lions in Africa cannot live by consuming millions of tons of insects, tigers cannot live by eating smaller prey weighing less than 50 kilograms in tropical Asia. Its all rooted into hunting efficiency and how many prey animals weighing over 50 kg that tiger can kill per year.
In order for GTRP to become a successful longterm tiger ecology and conservation project with functional objective to double the tiger numbers, ecological study of tiger focusing several key sets of elements are at fundamental and paramount importance. Identifying key conservation areas where at least 10 – 25 breeding population size is present, followed by joining these population by creating effective wildlife corridors (aka dispersal corridors) to increase tiger population dispersal and gene flow will help increase reproductivity, survival chance and population status in the long run. Several wild tiger populations pivoted around with breeding tigers are necessary in this remit. Equally, protecting prey population base at level that meets tigers annual nutrition budget is at critical importance. Annual tiger and its prey survey that embrace science would enable tiger ecologists to effectively monitor demographic patterns over spatial and temporal scales : essentially vital to understand whether conservation actions are in fact helping to increase tiger and its prey base or simply not working. Doubling the tiger numbers largely depends on whether a tiger nation has laid out a tiger conservation action program based on solid science of ecology, wildlife biology, statistical modeling and other interdisciplinary subjects in the field survey to data processing and analysis. Results can then be translated in laymen terms to educate policymakers, local conservation leaders, general public and law makers across tiger nations where probability of long term survival for tiger is relatively high. These in turn will help create sufficient political synergy and power to safeguard this awesome and magnificent animal that is now very near to extinction. George Schaller, who pioneered the scientific study of wild tigers over five decades ago in India, warns us that: “Future generations will be truly saddened, if this century has so little wisdom, compassion, such lack of generosity of spirit, that it eliminates one of the most dramatic animals that has ever lived on this planet.”