In Kandal’s O’Romchek village, and several others around the Kingdom, the residents have developed a unique and lucrative symbiotic relationship with the local bats

On a clear morning in O’Romchek village in Kandal province, beneath a strip of palms squeezed between two verdant fields of cassava and morning glory, an old man swept at bat faeces. They were fresh pellets, coffee-coloured and sweetly pungent. Some still fell from the chittering palm trees above, where the 87-year-old farmer, Mao Koy, kept six artificial bat roosts. Six other palm trees also possessed man-made roosts but belonged to his neighbors.

The guano, which Koy sells to farmers around Phum Cham district in large sacks as fertiliser, provides 100 per cent of his income, about $100 a month. Bald, nearly toothless and lean to the point of emaciation, with sun-dried leathery skin, he explained this week that he had been profiting off the bat droppings since the early 1970s, with a gap during the Khmer Rouge era (1975-79).   

“I collect this guano everyday for selling here. It’s not too hard,” Koy said.

The method behind the harvest is simple. The roost is made by stringing together a collection of palm leaves with wire. It is then hauled up to the top of a palm tree and fastened there, so that the dead leaves hang downwards below the live palm leaves. Silhouetted from a distance, roosted trees look like monster-sized dandelions.

Soon, the insectivorous bat colonies arrive. When they take up residence, their guano – or “black gold” as Asian bat expert Neil Furey calls it – collects daily at the base of the trees in putrid, inky rings. Some harvesters wrap netting or tin flaps around the trunks to ward off snakes. After that, it is all pretty maintenance-free. It is a win-win too – as the bats giveth profits, they taketh away mosquitoes.

Guano is harvested for consumption as fertiliser across the world. But this particularly symbiotic form of small-scale harvesting is unique to Cambodia, according to Furey, who accompanied Post Weekend’s trip. It is mostly seen in Kandal, Kampong Cham and Takeo provinces.

Yet despite the special practice having existed here for generations – many farmers interviewed by Furey dated it back to their ancestors – Furey said that it has been largely spared from scientific scrutiny. Little is known about its origins or number of practitioners.

Dos Chantha, Koy’s neighbour, explained that she began the practice 10 years ago after she noticed another neighbour making good money doing it. During the buggy wet season, when the bats are at their most wasteful, she adds about $75 to her regular farming profits.

Chantha added that while many in O’Romchek village are fond of bat meat, “the village knows I take care of them, so they don’t hunt my bats”.  

The most difficult part of the practice, Chantha reported, was managing the roosts. The leafy bundles had to be changed once a year, as they become infested with mites and other parasitic pests over time. Like Koy, she did not do this herself but hired a specialist.

That was Chea Jon, a roost-maker extraordinaire from the neighbouring Baren Krom village. He happened to be cycling by at the moment and Chantha called him over as he passed.

Jon was short, with slender, muscled legs, a filthy shirt half-unbuttoned and one inwardly crooked eye. At 65 years old, he had been hanging bat roosts for 35 years and he carried the self-assured swagger of a self-made go-getter.

“There’s nothing hard about it for me,” he shrugged when pressed about the difficulties of scaling a palm tree with nothing but his hands and a piece of looped palm fibre he called a kroleang roped around his ankles.

Jon speculated that for novices, the hardest part would be nerves. “If you fall, you die,” he quipped, looking down at his bare feet. To demonstrate, Jon walked through the fields to one of Chantha’s trees, tied a krama round his waist, attached himself to the trunk with a bear hug and like a caterpillar slithered up towards the chittering bundle of dead leaves and live bats.

“If I wasn’t seeing this myself, I wouldn’t believe it,” muttered Furey, his neck craned up at the fast-ascending roost-maker. Suddenly, Jon’s earlier boasts that he could hang 10 roosts in a single morning seemed believable.

An hour south at Saang district’s Prek Sleng village, behind the local monastery, was a large clearing of more than 30 very tall palm trees each with a bat roost. It was replacement time and the ground was covered in piles of browned, mite-infested, palm bundles as well as stacks of green, newly bundled ones, ready to be hung and colonised by lesser Asiatic yellow bats (Scotophilus kuhlii).

Owner Hoerm Oerun, a large woman with a purple krama tied round her head, claimed that her guano plantation was the biggest around. While chewing a wad of tobacco, Oerun said that she entered the bat business 30 years before with her late husband. She also farms bananas.

Despite relying on word of mouth, Oerun said her bat business was booming. Wholesale buyers come from as far as Kampot to buy her guano, which she sells for about $11 a sack.

But Oerun must be heedful to finish all her poo peddling by May. During the rainy season, her low-lying plantation floods. Unfortunately, guano does not float.