With the advancement of technology that has caused a boom in agricultural production over the past four decades, more and more farmers are opting for chemical and mechanical methods to get rid of rats and save their crops in the fields and warehouses.
Ordinary farmers use these methods to kill the rats due to ignorance about natural means, which refer to using other organisms to control rodents.
The government, too, promotes eliminating rats effectively – by using different types of traps, poisons and gas tablets. Moreover, it spends crores of taka to observe rat culling week every year, when top hunters are rewarded.
In 2020, the government prepared a list of over 600 rat hunters from across the country to save the crops, mainly paddy plants.
But some of these chemical and mechanical tools adversely impact the ecological balance.
Take the case of the abrupt use of chemical fertilizers and pesticides as an example: these are killing and driving away insects, which are essential for pollination and crop growth.
How harmful are they?
According to officials of the Department of Agricultural Extension (DAE), rodents of black, hairy and small-tail varieties are usually seen in the paddy fields and rice warehouses around the year. They spread fast during the Aman season.
The authorities identify the rodents as a menace and take stringent measures to eliminate them before the breeding season begins.
They say rats gobble up around 10% of the total rice and wheat production, while prolonged floods, drought, cold, pests and pestilence affect the country's food security. Another government estimate suggests that rats damage 700,000 tons of food grains annually.
“Farmers, millers and traders consider rats a significant pest in all the rice-producing countries in Asia…rats attack the plants and cut the sheaves when the paddy is almost ripened,” says an article in the “Krishi Seba” magazine published by the Ministry of Agriculture. If paddy is stored in a warehouse for three months, rats may damage 5-10% of the crops.
Written by three top scientific officers of the Bangladesh Rice Research Institute (BRRI), the article focuses on the lifecycle of rats and how to eliminate them by using different means.
Thoughts on natural ways
The BRRI article also sheds light on the organic method to prevent the spread of rats in crop fields, but only a few sentences are at the bottom.
It says: “Proper management of protection and breeding of rat eaters will reduce the problem to a great extent, along with maintaining the food chain of the ecosystem.
“Rats are the main food of snakes, monitors, jungle cats, owls and foxes. Steps should be taken for conserving their natural environment, breeding, and rearing at the farmer level.”
These animals are a blessing for agriculture but are disappearing from many places due to rapid urbanization, habitat loss, and pollution, say farmers who grow safe food by using organic fertilizers and natural pest control measures.
Due to superstitions, fear and lack of knowledge about the benefits, farmers as well as common people kill these predators, mainly snakes and monitors.
Daarash: Natural pest control
Such a friend is a rat snake or daarash: a non-venomous fast-crawling species (scientific name Ptyas mucosa). Rat snakes can be light grey to olive green, yellow, and even jet black.
They are generally seen in forests, wetlands, paddy fields, farmland and muddy places, and prey on small reptiles like frogs and rats.
People mistake the rat snakes as being poisonous since they are big, like the cobra, and they roam around human habitats, including the kitchen and cow shed. There are superstitions that rat snakes have spines on the waist or tail.
Many village people still believe that rat snakes attack cows and suck their milk because they do not know that snakes with split tongues cannot suck at all and that it is an insect that bites the cows.
Maruf Ahmed is a youth engaged in growing safe food and teaching children in a char area in Kurigram. He promotes the conservation of rat snakes among local farmers and also on social media.
“A rat snake that lives in cropland kills all the rats within a three-acre area. According to estimates by experienced farmers, an adult rat snake kills 70-80 rats a year.
“If those rats were alive and bred, their families would have multiplied to 20,000-30,000 after one year,” he said, urging the government to run awareness campaigns and explain the need for protecting rat snake habitats.