“When sparrows bathe in the dust, it rains,” they would say.
But as climate change alters weather patterns in northeast India, it is changing traditional knowledge – and threatening local birds that long have helped farmers control pests in their fields.
Birds are “the real friend of farmers,” says Prabal Saikia, an agricultural ornithology specialist at the Regional Agricultural Research Station (RARS) in North Lakhimpur, in India’s Assam province.
But these days, “the decline in the bird population has increased the insect population, thereby increasing crop damage,” he said.
Cattle egrets, for instance, known locally as bu bog, can eat more than 400 insect larvae an hour at ploughing time. But the egrets, which nest in bamboo groves near farmers’ homes, are increasingly seeing their nests washed away by increasingly heavy rains that now fall at nesting time.
“Now, because of climate change, there is (early) rain during the breeding season,” Saikia said. In some cases “the heavy rains devastate the bamboo groves, which fall down and the small nestlings fall down and die.”
A survey found that the egrets appear to have begun breeding earlier in the year than normal as a result of changing conditions, the scientist said.
BIRDS AND FOOD SECURITY
In a region where more than 70 percent of crop damage is the result of insects, plant diseases and rodents, birds that eat insects and rodents “mean a lot in terms of food security,” Saikia said.
That’s one reason the researcher is studying traditional lore and local bird populations, and working to protect them by meeting with farmers, producing leaflets in local languages and giving talks on radio and television stations.
Saikia and his team have been working on an effort called the All India Network Project on Agri-Ornithology. The project, taking place in regions across India, aims to identify birds in agricultural ecosystems, and help conserve those that are beneficial while managing others that create problems for farmers by eating grain. The study, sponsored by the Indian Council of Agricultural Research based in New Delhi, also aims to analyse the impact of climate change on the birds.
Saikia’s research station has identified 26 species of beneficial local birds in the agricultural fields of Assam.
One is the cattle egret, traditionally protected by farmers for their help in protecting farm fields from harmful insects.
EGRETS AND CROP PESTS
The breeding of the egrets is closely related to the timing of cultivation. The peak breeding season is from March to August. In Assam, rice transplanting starts in June and July. During this period, the local birds feed their chicks with the caterpillar or larvae of the insect pests.
But shifting weather patterns appear to be upsetting the balance, Saikia said, particularly if heavy rain disturbs nests or unusual temperatures upset the egg incubation period.
Other birds, like the spotted owlet and the barn owl that hunt rodents, have seen population declines as a result of deforestation in the region as farming fields expand to meet population growth.
And some birds are seeing their food sources change as climate shifts lead to the disappearance of some traditional plant species and affect fruit trees, Saikia said.
To protect and better understand threatened plants and trees that are important to birds, the scientist’s team is collecting samples of the species and planting them in their research station.
Alarmed by a decrease in the number of local birds, Saikia has also devised innovative techniques to help them, such as nests made from shoe boxes and earthen pots that farmers can build and site near their homes.
Farmers have supported the effort.
“I learned how to make the shoe-box nest and put it up in my house. I could see a lot of sparrows coming now. I am encouraging my neighbours to put this cost-effective nest in their respective houses,” said Kanak Sonowal, 35, a farmer from Dagal Dubi village.
He said he was also “trying to explain the importance of these indigenous birds to other farmers through age-old proverbs.”
Other farmers have fought to protect threatened wetlands that provide habitat for both local and migratory birds.
Teresa Rehman is a journalist based in Northeast India. She can be reached at www.teresarehman.net.