Canopy corridors and tree-dwelling mammals in Gujarat's forests

When you walk through a tall forest in Australia, whether the wet sclerophyll gullies of the Otways or the open eucalypt woodlands along the Great Dividing Range, it is easy to take for granted that a squirrel glider or a possum can travel from one patch of bush to the next without touching the ground. That sense of unbroken green above is exactly what forest canopy connectivity provides, and it is a feature of healthy forests everywhere, including the dry deciduous woodlands of western India.

Gujarat sits at the western edge of the Indian subcontinent, and its forests are often thought of as sparse and semi-arid, yet many of them still hold remarkable arboreal mammals. Species such as the Indian giant squirrel and the common palm civet rely on continuous branches to feed, den and escape predators. When the canopy is broken by roads, farmland or settlements, these animals lose safe passage, and the long-term viability of their populations comes under threat.

Australian readers may already be familiar with this concept through local conservation programs. Initiatives such as the Great Eastern Ranges corridor in New South Wales, koala-friendly crossings in south-east Queensland, and wildlife overpasses along the Pacific Highway are all attempts to re-establish tree-based connectivity for species that refuse to come down to earth.

Why tree-dwelling species depend on continuous crowns

Arboreal mammals have evolved to live their entire lives above the forest floor. Their bodies are adapted to climbing, leaping and gliding, and their behaviour is shaped by the availability of overhead cover. A connected canopy lets an individual move between feeding trees, locate mates, avoid ground-based predators and access seasonal resources that may be scattered across many hectares.

When that connection is severed, even small gaps in the canopy can become serious barriers. Many tree-dwelling mammals will not cross open ground of even ten or fifteen metres, because the risk from predators or exposure is too high. Over time, populations on either side of the gap become genetically isolated, and local extinctions become more likely. This is the same dynamic that Australian ecologists have documented for squirrel gliders and yellow-bellied gliders, where felling of paddock trees in New South Wales has fragmented populations across otherwise cleared farmland.

Connectivity is also about more than physical movement. Trees communicate through their roots and fungal networks, and the mammals that move through the canopy help disperse seeds across the landscape. Disconnected patches lose this subtle ecological exchange, and the forest itself becomes less resilient to drought and fire, two pressures that are familiar to land managers in both Gujarat and Australia.

The Gujarat landscape and its forest base

Gujarat stretches from the arid Rann in the north to the moist coast of the south, and its vegetation reflects this wide climatic gradient. The state falls into several agro-climatic zones, each with its own forest character. In the south and east, where rainfall is more generous, moist deciduous forests once supported rich arboreal communities. In Saurashtra and Kutch, the forests are drier and more open, dominated by teak, khair and a variety of acacias.

According to the forest area figures published by the Gujarat Forest Department, the state's recorded forest cover is a modest proportion of its total geographical area, which makes every remaining patch all the more important for wildlife. Even within those recorded forests, the distribution of trees tall enough to support a continuous canopy is patchy, and rivers, roads and farmlands frequently interrupt the treeline.

For arboreal mammals this means that suitable habitat often exists as a series of islands rather than a single connected woodland. The challenge for conservation is to think about these forests not as isolated blocks but as parts of a wider landscape, where every surviving tree along a field boundary or village edge could one day form part of a linkage.

Key species that need overhead connections

Several tree-dependent mammals make their home in Gujarat's woodlands, and each has slightly different requirements. The Indian giant squirrel, one of the largest squirrels in the world, builds its nests high in the canopy and rarely descends to the ground. It needs tall trees with spreading branches that touch those of neighbouring trees, allowing it to travel hundreds of metres without ever touching the earth.

The common palm civet is more adaptable and will sometimes forage on the ground, but it still relies on continuous tree cover for safe sleeping sites and to move between fruiting trees. Bonnet macaques and Hanuman langurs, familiar to many visitors from the more wooded parts of the country, also depend on connected canopies to move between sleeping groves and feeding areas.

The loss of overhead connectivity affects each of these species differently. Squirrels and langurs are particularly sensitive to canopy gaps and tend to disappear first when habitat is broken up. Civets and macaques can persist a little longer because they are more willing to use the ground, but eventually they too become locally scarce. The pattern mirrors what has been seen in Australia, where the loss of paddock trees and bushland fragments has led to steep declines in koalas and greater gliders, both of which require tree cover to survive.

Saurashtra's dry deciduous forests as a special case

Saurashtra, the peninsula that juts into the Arabian Sea from Gujarat, holds a distinctive type of dry deciduous forest that has long been recognised for its ecological value. These forests, with their mix of teak, sadad and timru trees, support a surprising variety of wildlife, including many arboreal species that depend on the continuity of the canopy.

The dry deciduous forests of Saurashtra face particular pressures. Fragmentation here is driven by agricultural expansion, wind energy installations and the steady encroachment of villages along the woodland edges. Where once a squirrel could move from one end of a forest range to the other without descending, today it may encounter several breaks in the canopy within a single kilometre.

Australia offers a useful comparison. The semi-arid woodlands of Western Australia and inland New South Wales have faced similar pressures from clearing for wheat and sheep, and conservationists there have worked for decades to restore paddock trees and replant native species along fence lines. The lessons learned around Perth and Dubbo are directly relevant to what is happening in Saurashtra today.

Building resilience through linked canopies

Restoring forest canopy connectivity requires a combination of careful planning, local engagement and long-term commitment. In Gujarat, this means protecting the existing tall trees that form the backbone of the canopy, while also planting native species along degraded edges to gradually extend the network outward. Village communities, who often hold informal tenure over nearby woodlands, play a critical role in these efforts.

The state's forest cover data shows where gains have been made and where further work is needed, and it is a useful starting point for anyone wanting to understand the scale of the challenge. Beyond planting, conservationists in both Gujarat and Australia are increasingly turning to natural regeneration, fencing off degraded areas to allow native trees to recover on their own, and using landscape-level planning to identify priority corridors.

Australian legislation offers another parallel. The Environment Protection and Biodiversity Conservation Act 1999, commonly known as the EPBC Act, requires that any project likely to have a significant impact on matters of national environmental significance be assessed for its effects on habitat connectivity. In Gujarat, the forest department plays a similar coordinating role, working to ensure that infrastructure projects do not sever the very corridors that wildlife depends on.

Across both countries, the message from ecologists is consistent. Protecting isolated patches of forest is not enough on its own. Arboreal mammals, perhaps more than any other group of animals, depend on what happens between the patches, on the connective threads of canopy that link one woodland to the next. When those threads are allowed to fray, whole populations can unravel. When they are carefully rewoven, forests regain their resilience, and the animals that depend on them have a real chance to thrive.

If you are inspired by what you have read, take a moment to explore the Gujarat Forest Department website for more information on the state's woodlands and wildlife. Whether you are based in Melbourne, Brisbane or a remote community in the Pilbara, your curiosity and your support for habitat connectivity anywhere in the world helps build a global movement for connected, resilient forests.