The forest fire in Karnataka’s Bandipur Tiger Reserve that destroyed thousands of acres of forest between February 21 and February 25 could have been avoided, or at least mitigated, with better forest management practices, several forest and wildlife researchers said.

Forest authorities are in the habit of suppressing all fires in forest areas, researchers said. Instead, the authorities should be using controlled burns during winter months to clear flammable undergrowth to prevent larger, more intense and more damaging fires from breaking out during the dry summer months.

The forests of Bandipur used to be a hunting park for the Maharaja of Mysore and were declared a tiger reserve under Project Tiger in 1973. The park, along with contiguous forests of the Nilgiri Biosphere Reserve that includes the forests of Nagarahole, Wayanad, Mudumalai and Sathyamangalam across Karnataka, Tamil Nadu and Kerala, has the largest tiger population in India – about 382 at last count.

The park is home to several other large mammals like elephants, gaurs, sloth bears, antelopes, jackals, dholes and Indian rock pythons, some of which are endangered, about 250 species of birds and an immense range of vegetation. The park is important as part of one of the most biodiverse ecosystems in the world.

The February fire in the dry deciduous Bandipur forest system was particularly severe because a good monsoon last year promoted the lush growth of grasses on the forest floor, but a deficient winter monsoon led to this growth drying out, leaving plenty of flammable material behind. When the fire broke out, wind speeds that are normally about 5 kmph in this region went up to 25 kmph and helped the fire spread rapidly, said Punati Sridhar, principal chief conservator of forests in Karnataka.

Sridhar said that the massive five-day fire affected about 3,400 hectares of the reserve. Other reports, however, say that satellite data from the Indian Space Research Organisation shows the fire may have spread across more than 4,400 hectares.

Sridhar claimed that the Bandipur fire was a ground fire that consumed the flammable undergrowth. At the same time, the Forest Department does not yet have an assessment of tree damage that has occurred and has ordered a study to gauge this.

The Bandipur forest reserve is spread over 87,400 hectares of land. Forest officials have arrested two men from a nearby village for allegedly starting the fire to keep tigers from attacking them and their cattle.

Fire management flawed?

For many years now, scientists working on forest and wildlife conservation have said that India’s approach to forest fire management is flawed. The country has had a long history of its people using fire as a tool for land and forest management, which changed when the British created the Indian Forest Service and began to value forests primarily for timber. In this view, fire was seen as essentially destructive and needing to be suppressed.

Conservationists recommend controlled fires in the winter months to prevent destructive wildfires in the hotter and drier months. “Cool season burning removes inflammable material and promotes growth of new grass which is rich in protein and very good for ungulates,” said Asir Jawahar Thomas Johnsingh, conservation biologist and former dean of the Wildlife Institute of India. “Fires will occur, but if cool season burning is carried out, the intensity will be less and the fire will not jump from one place to another.”

In a 2017 paper called Notes from the other side of a forest fire in the Economic and Political Weekly, a group of researchers point out the Indian Forest Service has carried that British legacy on in current forest management practices.

Current Indian laws strictly ban fire from Indian forests. The Indian Forest Act of 1927 makes it a criminal offense to burn or to allow a fire to remain burning in reserved and protected forests. The Wildlife (Protection) Act of 1972 further bans setting fire in wildlife sanctuaries. The exception is the use of controlled burning by the Forest Department. Yet, the practice has not been adopted effectively to control forest fires.

Fire factors

The authors of the 2017 paper point out that there are two major factors that contribute to forest fires – fuel load or the amount of biomass available to burn, and flammability or the readiness of the fuel to burn. Flammability depends on a range of environmental conditions such as low humidity, high temperatures and high wind speeds that are out of human control. Fuel load, however, can be reduced by controlled burning of undergrowth periodically.

Jayashree Ratnam, wildlife scientist at the National Centre for Biological Sciences and one of the authors of the paper, outlined how cool season burning should be carried out. “Cool season burns should be carried early in the dry season, under cool and non-windy conditions, in planned blocks and demarcated by fire lines,” she wrote in an email to Scroll.in. “These blocks can be rotated around the forest such that any given block burns once very few years (based on what we know from other comparable savanna systems, fire return intervals of 3-5 years may work, but these will have to be fine-tuned for each site based on its climate and productivity).”

Ratnam and her co-authors also point out in their paper that local tribes like the Soligas used to set early summer fires as part of their complex ecological and agricultural practices, and this benefited the health of the forests. The Soligas now find that fire suppression policies have allowed the growth and spread of the invasive weed Lantana camara across the forest, which also serves as fuel for forest fires, the paper says. According to the Soligas, fire suppression has also allowed the growth of plant parasites on trees.

In Bandipur and many other parks in peninsular India, the grass understorey in forests has, in the recent past, been replaced by dense thickets of Lantana camara, which may be changing the behaviour of these fires. Ratnam said there is an urgent need for research on exactly how Lantana is having an impact on the intensity, speed and height of fires.

‘A positive role’

In June 2018, the Ministry for Environment, Forests and Climate Change and the World Bank released a joint report on Strengthening Forest Fire Management in India, which recognises that “the controlled use of fire may play a positive role in the management of fire-adapted forests”.

The report noted a weakening of traditional land practices in Uttarakhand, for instance, where a reduction in the practice of controlled burning to promote fodder or to clear forest litter has led to an accumulation of fuel loads and created the potential for more severe and destructive fires.

The report also found that data on the performance of controlled burning is not readily available. According to information from state forest departments, the practice has been most common in Uttarakhand and Himachal Pradesh. In some states, the area of controlled burning required is not specified. Three-fourths of the forest officials surveyed said that controlled burning was required in their areas but nearly two-thirds said that it was not regularly performed largely due to the lack of resources.

As the report summarises, “in some forests, fire may be used in a controlled way to manage fuel loads, check invasive weeds, and eliminate pathogens. In other forests that are less adapted to fire, it should be excluded.”

Ratnam said Bandipur is likely to be adapted to periodic fires. “Bandipur, with its open canopy of deciduous trees set in an understorey of grasses is functionally a savanna that likely evolved with fire,” she said. “It is similar to nearby BRT [Wildlife Reserve] where the very old burning practices of local tribal communities are well documented. Evergreen forests such as the rainforests of Silent Valley [in Kerala], for example, are true forests that are not adapted to burning.”

What causes more damage?

Principal chief conservator of forests Sridhar defended the Karnataka Forest Department’s method of fire management through fire suppression. He said that forest authorities in the region stopped the practice of cool season burning almost 40 years ago when undergrowth used to be cut, burnt and even used to make charcoal. Now Karnataka forest officials only cut and burn growth along fire lines.

“Even cool season burning kills smaller animals and insects and affects forest regeneration,” said Sridhar. “The method of fire suppression helps protect biodiversity.”

Sridhar said that even as recently as 2000, forest officials used to carry out controlled burns in grasslands such as in Kudremukh. “There were 12 varieties of snails and many kinds of orchids and everything would [burn]. So, since then, we have stopped controlled burns.”

Forest researchers, however, point out that damage from frequent controlled low-intensity burns in forest systems adapted to fires is likely to be much lower than damage from uncontrolled high-intensity fires that result when biomass builds up over long periods.