“What we have learned was that conservation depends not only on protection but also on connection,” wrote Thomas E. Lovejoy and Edward O. Wilson in The New York Times in 2015. With the emerging awareness and focus on the importance of geographic connectivity of wild habitats owing to massive population decline among species and even extinction, protection and restoration of wildlife corridors is the need of the hour. In a rapidly altering world, where fragmentation due to habitat loss is destroying biological diversity, corridors prove to be useful conservation tools.
On the eve of International Tiger Day 2020, Wildlife Biologist with Wildlife Conservation Trust (WCT) and a member of the IUCN’s Connectivity Conservation Specialist Group, Milind Pariwakam, tells Purva Variyar about the burgeoning threat of linear infrastructure on tiger populations in India, and why habitat connectivity needs to be secured at all costs.
Photo credit: Anish Andheria
Q: Hello, Milind. Having asked around, I know that the term ‘wildlife corridor’ is still a vague concept in the minds of many. No one better than you to explain to our readers what a wildlife corridor is and why it is so important.
Simply put, a wildlife corridor is a suitable natural habitat that enables free movement of wildlife from one forest to another. Some wild animals may exhibit a one-time movement such as ‘dispersal’ (e.g. a tiger) while some other animals may exhibit regular (seasonal) movements (to and fro) like migration (e.g. elephant, several species of birds etc.)
However, recent advances in the field of connectivity conservation have demonstrated and now focus on ‘ecological connectivity’ which is defined as ‘the unimpeded movement of species and the flow of natural processes that sustain life on Earth.’ Therefore, ‘corridors’ in their broadest sense are important not just for wild animals, but for ecosystems and ecological processes to function naturally.
In the Indian context, our Protected Area network covers just 5% of the total land area. As a result, the number of wild animals that inhabit Protected Areas (PAs) is very small and they need to disperse/migrate from one area to another. In the Indian legal context, any patch of land that connects one PA to another is called a ‘corridor’ and enjoys the same level of protection from anthropogenic/development pressure as any PA. It is a myth that corridors in India do not have legal protection.
Q: Around 4,000 tigers roam the wilds globally, today. This number is less than 5% of the tiger’s historical population. How important is it to maintain and restore connectivity within the tiger’s severely fragmented and shrunken range to prevent its extinction?
The current tiger populations are spread across a network of small PAs which are connected by corridors with about one fourth of tigers outside PAs. Most of our tiger populations are small and thus, highly dependant on corridors for ‘immigration’ and ‘emigration’ of individuals. The National Tiger Conservation Authority (NTCA) estimates that to be viable on its own, a tiger population needs to carry a 100 adult tigers. There are a handful of tiger populations within PAs in India such as Corbett, Pench (both Maharashtra and Madhya Pradesh), Kaziranga, Nagarahole-Bandipur-Mudumalai-Wayanad complex that fulfil this criterion.
Barring these few examples, the rest of our tiger populations are highly dependant on corridors for their long-term sustanence. Further, with declining prey densities and other more endangered co-predators occupying the same landscape, tiger corridors benefit not just tigers, but the entire gamut of wild animals that inhabit our forests. In other tiger range countries (TRCs), which harbour lesser number of tigers and in lower densities, corridors prove to be even more crucial.
Q: Research shows that tiger densities in several wildlife corridors in India are comparable to that of some of the tiger reserves in the country. And yet, many of these corridors are languishing from overexploitation, habitat degradation and lack of protection. Why aren’t wildlife corridors given the same amount of respect, conservation attention and protection as the tiger reserves, national parks and wildlife sanctuaries of the country?
Yes. Several reserve forest areas such as the Landsdowne/Ramnagar forests adjoining Corbett Tiger Reserve and Brahmapuri adjoining Tadoba-Andhari Tiger Reserve support relatively large tiger populations. Indeed, these two areas may have more tigers than many of our tiger reserves themselves. The bulk of our corridors are classified as reserve forests which enjoy the same degree of protection as a national park or wildlife sanctuary. In a densely populated country such as India, there are many thousands of villages within these reserve forests and millions of human’s dependant on them which complicates the situation.
Project Tiger envisaged the protection of corridors and the value of connectivity right from its inception back in 1973. Indeed, many of our statutes and guidelines also incorporated this. However, the preliminary objective was for recovery of wild animal populations such as the tiger which is easier to achieve in PAs. Now, our focus has to move on to corridor conservation. Our forest management has to focus on maintaining ecological connectivity and restoring it wherever it has been lost.
Further, changes and amendments to the rules and guidelines have made it even more easy to divert reserve forest land for development purposes, putting massive pressure on our natural ecosystems by fragmenting and degrading them. We need to inform policymakers to bring ‘ecological connectivity’ to the forefront instead of just managing our wild animals from a ‘numbers’ perspective.
Q: I read in one of your studies that linear infrastructure (roads, railway lines, power lines and canals) pose the single largest threat to the demographic viability of tigers in India? How so?
Yes, several studies by multiple agencies, including the World Bank, have made this claim and we have referred to it in our study report as well. I completely agree with this view. Scientific studies show that linear infrastructure such as roads are almost everywhere and we have very few large forest patches left that are devoid of roads. The pace at which linear infrastructure construction is growing is a part of the immense nature of this threat. Due to its linear nature, infrastructure such as roads, railways, canals tend to bifurcate and fragment habitats completely. They also form invisible barriers as animals refuse to cross the linear infrastructure or those that attempt to cross them often end up getting traumatised, injured or killed.
This map shows national highways cutting through crucial wildlife corridors connecting some of the important Protected Areas in Maharashtra. © WCT
Q: Interestingly, though linear infrastructure requires lesser area to be diverted compared to other types of infrastructure, their negative impact on wildlife is visibly disproportionate to the area diverted? Could you explain?
As compared to other types of infrastructure such as mines or dams, which may require hundreds of hectares of forest land to be diverted for their development, a road or a railway line requires much less forest land area to build. An average proposal for a road needs diversion of less than 10 hectares of forest land. This small quantum of forest land required though is misleading and often regulatory authorities tend to clear the proposal right away on this basis. However, this smaller requirement of forest land is spread across a considerable length of the road. That means the entire habitat is bifurcated/fragmented and the linear infrastructure becomes a barrier for wild animals trying to move from one place to another. Thus, a linear infrastructure which forms a barrier often has an impact on the small populations of wild animals living in PAs, which may be far away from the linear infrastructure itself. Thus, the negative impact on the viability of these wild animal populations is immense and grossly disproportionate to the small amount of land diverted.
Q: India’s road network has grown to become the second largest in the world. And we don’t intend to stop there. The building of road network that is progressing at a rate of 22 km./day presently, is slated to be ramped up to 41 km./day by the government. What does this spell for tigers and other wildlife of the country, and their habitat connectivity?
We are upgrading roads everywhere. From 1 to 2, 2 to 4 or 6 or 8 lanes. Roads, that in our lifetimes were upgraded to 2 and 4 lanes are now proposed for further expansion. What this means is there is exponentially more pressure on lands within PAs to build roads, railways and canals.
All of our corridors (without exception) are threatened by the prospect of unmitigated linear infrastructure development. Railways are also being expanded at a fairly rapid pace. The addition of a 3rd and 4th line on the East-West and North-South alignments while being a threat, can be looked at as an opportunity to incorporate mitigation. Similarly, the new Bharatmala project also cuts across multiple corridors. However, National Highway Authority of India (NHAI) has clearly spelt out in their own guidelines that forest and wildlife laws need to be followed in the Bharatmala project with respect to both, diversion of roads to bypass PAs and other structural mitigation measures in case of corridors.
We need to be clear that in case of a linear project proposed through a PA where an alternate alignment is often not possible, expansion of any kind should be discouraged. However, on linear projects along corridors the best structural mitigation measures have to be implemented. In that sense, further expansion of roads under Bharatmala offers not just an opportunity to mitigate, but also restore connectivity lost in the past ten years of unplanned development! For example, the development of National Highway-6 (NH-6) in 2010 has increased the level of threat in multiple corridors in Central India. The proposed development of Economic Corridor 1 (EC1) under Bharatmala Pariyojana offers a chance to restore previously lost connectivity.
Q: With newer road building and road widening projects in the pipeline across the country, many of them, we know, will require forested areas and other eco-sensitive regions to be diverted. Do mitigation measures such as overpasses, underpasses, culverts, canal bridges, etc., feature in any of the current roadwork plans?
Yes. We have documented over 60 examples where the NTCA or theNational Board for Wildlife (NBWL) have imposed conditions such as overpasses etc. so that animals can find safe passage. There are a few more examples where statutory bodies such as Forest Advisory Committee (FAC) have also made similar recommendations. Therefore, it is definitely a growing positive trend. But, on the other hand, this is just the tip of the iceberg. The number of proposals that slip through the statutory clearance process without any safeguards are plenty.
The state of Maharashtra is a leading example in terms of the number of already functional mitigation measures or those under construction. It has tried to restore connectivity by ordering mitigation measures such as overpasses along the Gosekhurd Canal. The Samruddhi Mahamarg will possess tunnels, viaducts, fencing, overpasses and underpasses in the form of mitigation measures. NH-7 has underpasses and soon NH-6 and roads around Tadoba will also have underpasses. The diversion of the Akola-Khandwa Railway Line, bypassing the Melghat Tiger Reserve is one of the best examples of mitigation in recent times!
An aerial view of the world’s longest and India’s first dedicated and functional underpass for wildlife on NH-7, passing through the Kanha-Pench Corridor. An outcome of a decade-long battle by conservationists. Photo credit: Public Domain
Q: In a recent, positive news coverage of National Green Tribunal’s (NGT) directive to the Centre asking it to stick to NTCA’s plans and construct mitigation measures along various roads that cut through important wildlife corridors around Tadoba-Andhari Tiger Reserve, you told the TOI, “Reluctance to provide mitigation by Ministry of Road Transport and Highways will actually cost the taxpayer more money as project delays mean massive cost escalations.” Could you elaborate?
Road projects are funded under different models. Whichever the mode of funding, it is ultimately the common man who pays for the development, either via taxes on income, goods and services or toll for using the roads. Each year that a project gets delayed, inflation adds to the cost. We did some calculations on the NH-7 project which was delayed for a decade due to the NHAI refusing to incorporate wildlife mitigation measures. We found that on an average, the cost of mitigation measures went up by approximately 70%. So, if the NHAI had accepted the need for mitigation and built the underpasses a year ago, the common man would have been spared the additional project cost.
Q: If incorporating mitigation measures at the planning stage is the more logical and a financially more viable solution for linear infrastructure projects, why is this not the norm? Why do demands for implementing mitigation measures face so much resistance from the project proponents?
I think it is a mindset, which in the case of road projects is hopefully changing.
The infrastructure planners think that they are also doing the public a service by building infrastructure and find it difficult to digest that their project has negative impacts on the environment. The other issue is of the increase in project cost due to additional structures that need to be built which tends to distort project financial viability, especially if the incorporation of mitigation is an afterthought. Infra planers need to realise that the “polluter pays” principle applies to them also. If the project is damaging wildlife connectivity, it is the project proponent’s responsibility to build it and they cannot expect CAMPA money to subsidise the project. Nevertheless, in the case of most road projects, it is ultimately the common citizen who bears the burden, either via taxes or toll. Therefore, any failure to budget for mitigation in planning stage is squarely the responsibility of the infra developer/agency.
One of the major lacuna is the improper identification of corridors, which leads to delays in incorporation of mitigation measures in project planning. This needs to be rectified immediately by having better maps of corridors and making them available in the public domain. This has been WCT’s endeavour and we have managed to achieve this for the ‘Central India and Eastern Ghats Landscape’.
Q: The general lack of clarity regarding wildlife corridors and connectivity among the experts, scientists, park managers and policy makers has grave ramifications on the understanding and management of corridors in India. What is your approach when you find yourself in a room debating a infrastructure project with them?
I completely agree. Recently, we were working on a mitigation plan for a road passing through a corridor. The environment experts representing the infrastructure agency wanted a 3 km. wide and 150 km. long area fenced off to “create” a corridor in the middle of the Satpura-Melghat corridor. We tried to explain to them the key concepts regarding natural structural connectivity which exists and the need to preserve it. It is important to explain and educate the unaware so that a sense of importance of corridors is inculcated within them. Often, to explain concepts such as ‘genetic inbreeding’ I tend to make use of analogies. A simple example is that of how marriage between closely related members of a family is frowned upon in the human society. Such examples tend to drive the point home.
Another issue is that of resistance from infrastructure developers since they are always thinking of cost. In such cases, when no amount of reasoning works, one is then forced to drive home the point by emphasising on the various statutes passed by Parliament and their associated guidelines that support connectivity conservation and that protecting the corridors and/or mitigating the negative impacts are mandatory. One should never shy away from quoting the existing law.
Q: Could you list some of the most important wildlife corridors in India?
Some of the prominent wildlife corridors in India are the Kanha-Pench Corridor and the Kaziranga–Karbi Anglong corridor. Nearly all PAs of Western Ghats are connected with each other through a network of corridors.
However, assigning labels to certain corridors and calling them important leads to biases. We are currently vastly underestimating the number of corridors. For example, in the NTCA Corridors report, just 26 corridors are shown to be present in the Central Indian and Eastern Ghats tiger landscape. But, if we go by the legal definition, then there are almost 150 corridors that connect one PA to another.
However, some of the more famous ones get more coverage while lesser known, but equally important or more important ones get neglected. Coming back to the question of important corridors, to cite one example, the Kanha-Pench corridor is famous, but the Kanha-Tadoba-Indravati corridor is as important from a wildlife connectivity perspective, but never receives the same level of conservation attention.
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About the Author: Purva Variyar is a conservation and science writer at the Wildlife Conservation Trust, India.
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Disclaimer: The author is associated with Wildlife Conservation Trust. The views and opinions expressed in the article are her own and do not necessarily reflect the views and opinions of Wildlife Conservation Trust.