The yellow crazy ants are found in Papua New Guinea, Mauritius and other neighbouring countries.
Hundreds of people living in seven Tamil Nadu villages are facing a strange problem - ant infestation. According to the BBC, yellow crazy ants are attacking their livestock and affecting their crop yields, putting their livelihoods in danger. The locals say that the cattle owned by them have lost sight and dead chickens and sometimes even snakes are found dead in the villages. The yellow crazy ant (scientific name Anoplolepis gracilipes) is listed as one of the top 100 worst invasive species by the International Union for Conservation of Nature (IUCN).
The BBC said that the affected villages are situated in a hilly region around the Karanthamalai forest in Dindigul district. Most of the people here are farmers.
"As soon as we go near the forest, the ants climb on us, causing irritation and blisters. We can't even carry water to drink as they swarm that too. We don't know what to do," Selvam, a 55-year-old farmer, told the outlet.
These ants have been there in the forests around these villagers over the past few years, but the villagers say this is the first time they have appeared in such large numbers.
Forest officer Prabhu was quoted as saying by the BBC that an investigation has been ordered.
The outlet also spoke to Dr Pronoy Baidya, an entomologist who has done research on these ants. "They don't have any diet preferences. They eat anything and everything," he said.
According to Australian government's Wet Tropics Management Authority (WTMA), yellow crazy ants are named after their distinctive erratic and frantic movements when disturbed.
It further said that these ants have a slender body (4mm) and long skinny legs. The colour of the body is golden-brown with a darker brown abdomen. Though these ants can look for food in day as well as night, they are less active in intense heat and heavy rain.
These ants are dangerous because they do not bite or sting but spray formic acid, which can cause permanent blindness in animals, said WTMA. These ants are found in large numbers and can be controlled by insecticides.