F EW CREATURES can live comfortably on oil-palm plantations. The orderly rows of trees provide scant refuge for mammals trying to avoid predators and hunters. Monkeys struggle to swing on palm branches; birds have few places to nest. But for snakes, the plantations are an earthly paradise.

Snakes flourish because they have an abundant source of food. They feast on the swarms of rats that are attracted to plantations by the energy-packed palm kernels. Studies have found more than 400 rodents a hectare on palm-oil farms. Stacks of dead palm fronds give ample cover for rats and reptiles alike. According to a recent report by the International Union for Conservation of Nature, at least eight species of snake thrive on oil-palm plantations. They are often more prevalent on plantations than in neighbouring jungles.

On a plantation belonging to Cargill in the Indonesian province of South Sumatra, the medical centre is stocked with anti-venoms. A poster on the wall depicts several species of snake to help patients identify their attacker. Signs warning about pythons are dotted among the rows of oil palm. Workers are encouraged to wear thick gloves to reduce the risk of bites. Across Indonesia, media outlets routinely report stories of oil-palm harvesters getting gobbled up by enormous pythons.

But the snakes can also be a boon for oil-palm workers, who tend to be poorly paid. Snake skins can fetch $30 to $60 apiece, roughly a week’s wage. Many are shipped to Europe to become fashionable belts or handbags. Another money-spinner is to milk poisonous snakes and sell the venom.

For oil-palm companies, too, there are upsides. The snakes, after all, prevent even bigger infestations of rats, which would reduce yields. Indeed, some oil-palm firms wish for more snakes on their plantations. Agrocaribe, a Guatemalan one, set up its own snake hatchery.