WILDLIFE CONSERVATION

How the decline in India's harrier population hurts its farmers

On World Wildlife Day on Friday, a focus on a critical species that feeds on the locusts and grasshoppers that could damage crops.

Harriers are a group of birds that belong to the hawk family that are active during the day and mostly found in vast open plains and grasslands. There are 16 species of harriers distributed worldwide throughout tropical and temperate regions, and six of these species migrate to India from central Asia and neighbouring areas during the winter. They can travel between 3,500 km and 5,000 km during this migration. Studies on tagged harriers in Africa show that they follow different routes during spring and autumn migrations. We do not really know much about the migration of harriers from India – the routes they fly from, or their breeding grounds – but researchers once found that a tagged harrier from Gujarat migrated to Kazakhstan.

Like many other birds, harriers not only nest on the ground in their breeding areas, but also roost communally in large numbers in tall grasslands with a few occasionally roosting on trees. This is a behavior unique to harriers. So far, the world’s largest harrier roost has been reported from India – in Velavadar National Park in Gujarat where more than 1,000 birds converge every evening to roost inside the park. Harrier roosts can comprise up to three to five species roosting at the same site.

Rollapadu sanctuary in Andhra Pradesh. (Photo credit: Prashanth MB).
Rollapadu sanctuary in Andhra Pradesh. (Photo credit: Prashanth MB).

Harriers are solitary tireless wanderers scanning open agricultural lands, grasslands and thin scrub jungle relentlessly for insects, lizards, rats and birds to prey upon. Their diet varies with the harrier species in question. For instance, the small Montagu’s harrier preys on a large quantity of grasshoppers, while the slightly larger Pallid harrier prefers small birds. Hen harriers prefer larger birds, and the largest of them, the Marsh harrier, preys on big snakes as well as waterfowl like ducks, rails and small herons, and is also known to scavenge.

Harriers are also indicators of the health of grassland ecosystems. They feed on locusts or grasshoppers that can be harmful to agriculture. The late Roger Clarke, an expert on harriers from the UK, has surveyed harriers in Velavadar National Park. He estimated that harriers consume 1.5 million locusts each year in India mostly while foraging over dryland crops like jowar, maize and other millets. They are therefore economically important, and finding harriers in fields augurs well for the crops.

Harriers in decline

Though harriers are not a popular species like large eagles, falcons or vultures, birdwatchers and ornithologists have been recording their presence regularly across India for years. Some dryland harriers species such as the Montagu and Pallid harriers only dwell in savanna – grasslands with scattered tree growth – or just grasslands. These areas are among the most threatened ecosystems in India.

For instance, co-author T Ganesh’s monitoring of harriers at a roost site near Hyderabad for seven years from the mid-1980s found that the harrier population showed fluctuating numbers until the site was converted into a plantation. Another roost site near Bengaluru was lost as the habitat around it changed. Over the years we have documented numerous such cases from almost everywhere across the wintering range of harriers in India.

We know that most of our large-bodied animals, be it mammals or birds, are under threat. The alarming decline in the number of vultures followed by Great Indian bustards in India should lead to watchfulness about a similar decline in other species.

Based on the collation of information on harriers from literature and personal observation over 25 years, it is clear that a decline in the number of harriers is already underway. For instance, the Rollapadu bustard sanctuary in Andhra Pradesh once reported about 1,000 harriers in the mid-1980s. Now, less than 100 harriers visit it.

The decline in Rollapadu could be caused by multiple reasons such as the loss of grasslands due to the creation of the Alaganur reservoir, which submerged dry grasslands – the foraging area of harriers. Agriculture expansion due to drip irrigation, solar farms and excessive use of pesticides could be other factors. Several birds, including harriers, have died in the past after they ate insects that were killed by the spraying of pesticides. In birds of prey such as harriers, which are tied closely to the agriculture-grassland matrix, bioaccumulation of poison in the food chain can lead to death.

Spraying pesticides on a chilli crop. (Photo credit: Prashanth MB).
Spraying pesticides on a chilli crop. (Photo credit: Prashanth MB).

Shrinking grasslands

Further, natural grasslands have shrunk dramatically in semi-arid India and Africa over recent decades despite their being an important resource for cattle herding and traditional livelihoods. In India, grasslands are classified as wastelands, unfortunately. This makes them vulnerable to developmental projects and conversion to farmlands, solar farms, and plantations by private and government agencies. Many grasslands are also threatened by invasive species such as Prosopis juliflora and overgrazing by livestock due to limited grazing area elsewhere. All this leads to a decline in the health of the grassland ecosystem, and poses a threat to the fauna dependent on it such as wolves, bustards, harriers and several smaller species of birds and other animals of which we know very little.

Science can help

While it is hard to isolate the specific reason behind the decline in the harrier population, a combination of factors including changes in breeding areas, changes in their wintering areas and migratory routes could all affect their numbers. But unless we can monitor them in all these areas, the reasons for their decline will remain in the realm of speculation.We need good science to get a handle on what is happening to these species and ecosystems before we formulate policy to manage and conserve their nesting and roosting grounds. First, we need to put in place a proper monitoring system that would allow researchers to estimate the number of birds that migrate to India and how their population is changing. Unfortunately, studying migratory birds in India comes with a plethora of problems. Internationally, migratory birds are tagged with transmitters to track them across space and time. Such tagging of birds is not allowed in India due to quite unjustified reasons of national security.

Livestock graze on grassland. (Photo credit: Prashanth MB).
Livestock graze on grassland. (Photo credit: Prashanth MB).

Ironically, while researchers in India cannot study migratory birds in the country, those from abroad can easily do so using similar transmitters, which gives them information on where the birds arrive in India and their migratory pattern. In fact, researchers abroad are atleast a decade ahead of their colleagues in India in understanding migration patterns and the conservation of such species.

For instance, the Montagu’s harrier breed in agricultural farms in many parts of Europe, and tracking them has helped researchers see what agricultural patches they use and how these can be protected with the help of farmers. This is a successful model. It also allowed researchers to identify bottlenecks in their migration route, where conservation action could help the species.

Harriers differ from other grassland birds in the size of habitat they require. They may be commonly seen in large open areas but they require compact roosting sites that can be as small as one square km or even less. These small grassland patches can be identified if we could track birds. Once identified, these can be selected for regular systematic monitoring, conservation and sustainable grassland management for a number of species, not just harriers. With large patches of grasslands not existing in India, we need to shift our focus on conserving the remaining smaller patches, or even creating such small patches of grasslands to sustain biodiversity in India’s dry lands.

T Ganesh is a Fellow and Prashant MB is a Senior Research Associate with the Ashoka Trust for Research in Ecology and the Environment.

(Photo credit: Prashanth MB).
(Photo credit: Prashanth MB).
We welcome your comments at letters@scroll.in.
Sponsored Content BY 

How sustainable farming practices can secure India's food for the future

India is home to 15% of the world’s undernourished population.

Food security is a pressing problem in India and in the world. According to the Food and Agriculture Organization of the UN (FAO), it is estimated that over 190 million people go hungry every day in the country.

Evidence for India’s food challenge can be found in the fact that the yield per hectare of rice, one of India’s principal crops, is 2177 kgs per hectare, lagging behind countries such as China and Brazil that have yield rates of 4263 kgs/hectare and 3265 kgs/hectare respectively. The cereal yield per hectare in the country is also 2,981 kgs per hectare, lagging far behind countries such as China, Japan and the US.

The slow growth of agricultural production in India can be attributed to an inefficient rural transport system, lack of awareness about the treatment of crops, limited access to modern farming technology and the shrinking agricultural land due to urbanization. Add to that, an irregular monsoon and the fact that 63% of agricultural land is dependent on rainfall further increase the difficulties we face.

Despite these odds, there is huge potential for India to increase its agricultural productivity to meet the food requirements of its growing population.

The good news is that experience in India and other countries shows that the adoption of sustainable farming practices can increase both productivity and reduce ecological harm.

Sustainable agriculture techniques enable higher resource efficiency – they help produce greater agricultural output while using lesser land, water and energy, ensuring profitability for the farmer. These essentially include methods that, among other things, protect and enhance the crops and the soil, improve water absorption and use efficient seed treatments. While Indian farmers have traditionally followed these principles, new technology now makes them more effective.

For example, for soil enhancement, certified biodegradable mulch films are now available. A mulch film is a layer of protective material applied to soil to conserve moisture and fertility. Most mulch films used in agriculture today are made of polyethylene (PE), which has the unwanted overhead of disposal. It is a labour intensive and time-consuming process to remove the PE mulch film after usage. If not done, it affects soil quality and hence, crop yield. An independently certified biodegradable mulch film, on the other hand, is directly absorbed by the microorganisms in the soil. It conserves the soil properties, eliminates soil contamination, and saves the labor cost that comes with PE mulch films.

The other perpetual challenge for India’s farms is the availability of water. Many food crops like rice and sugarcane have a high-water requirement. In a country like India, where majority of the agricultural land is rain-fed, low rainfall years can wreak havoc for crops and cause a slew of other problems - a surge in crop prices and a reduction in access to essential food items. Again, Indian farmers have long experience in water conservation that can now be enhanced through technology.

Seeds can now be treated with enhancements that help them improve their root systems. This leads to more efficient water absorption.

In addition to soil and water management, the third big factor, better seed treatment, can also significantly improve crop health and boost productivity. These solutions include application of fungicides and insecticides that protect the seed from unwanted fungi and parasites that can damage crops or hinder growth, and increase productivity.

While sustainable agriculture through soil, water and seed management can increase crop yields, an efficient warehousing and distribution system is also necessary to ensure that the output reaches the consumers. According to a study by CIPHET, Indian government’s harvest-research body, up to 67 million tons of food get wasted every year — a quantity equivalent to that consumed by the entire state of Bihar in a year. Perishables, such as fruits and vegetables, end up rotting in store houses or during transportation due to pests, erratic weather and the lack of modern storage facilities. In fact, simply bringing down food wastage and increasing the efficiency in distribution alone can significantly help improve food security. Innovations such as special tarpaulins, that keep perishables cool during transit, and more efficient insulation solutions can reduce rotting and reduce energy usage in cold storage.

Thus, all three aspects — production, storage, and distribution — need to be optimized if India is to feed its ever-growing population.

One company working to drive increased sustainability down the entire agriculture value chain is BASF. For example, the company offers cutting edge seed treatments that protect crops from disease and provide plant health benefits such as enhanced vitality and better tolerance for stress and cold. In addition, BASF has developed a biodegradable mulch film from its ecovio® bioplastic that is certified compostable – meaning farmers can reap the benefits of better soil without risk of contamination or increased labor costs. These and more of the company’s innovations are helping farmers in India achieve higher and more sustainable yields.

Of course, products are only one part of the solution. The company also recognizes the importance of training farmers in sustainable farming practices and in the safe use of its products. To this end, BASF engaged in a widespread farmer outreach program called Samruddhi from 2007 to 2014. Their ‘Suraksha Hamesha’ (safety always) program reached over 23,000 farmers and 4,000 spray men across India in 2016 alone. In addition to training, the company also offers a ‘Sanrakshan® Kit’ to farmers that includes personal protection tools and equipment. All these efforts serve to spread awareness about the sustainable and responsible use of crop protection products – ensuring that farmers stay safe while producing good quality food.

Interested in learning more about BASF’s work in sustainable agriculture? See here.

This article was produced by the Scroll marketing team on behalf of BASF and not by the Scroll editorial team.