The Water Supplies Department is accused of indiscriminately cutting down an important species of climbing vine during slope maintenance in a country park. A wildlife concern group says that birdwood's mucuna climbing vines - though far from rare - are a food source for fruit bats and an important larval host plant for rare butterflies, including the golden birdwing. Carol Kwok Wai-ling of the online-based Hong Kong Wildlife Forum, said that in September she noticed a dense growth of mucuna vines and pods hanging from trees along a water course on a hillside near the entrance to the Pat Sin Leng Nature Trail in Tai Mei Tuk. When she returned last month to see if the plants had flowered, she was shocked that many climbers had been snipped from the trees after the Water Supplies Department completed maintenance on the slope. "I came back and the dense overgrowth had been cleared. I worry about the attitude the [department] has taken when conducting this slope work." Kwok said that even if the vines did not have statutory protection, the city's country park laws prohibit any unauthorised cutting, picking or uprooting of plants and felling of trees. Forestry regulations also protect rare climber species such as the India birthwort and the illigera - both of which can be found in Hong Kong's country parks. "But do the contractors tasked with the slope works even know if the vines they cut are a protected species or not? Were they even given the appropriate directions?" Kwok asked. The Agriculture, Fisheries and Conservation Department said it approved any work conducted in a country park and then granted a conditional licence. A spokesman said: "The Water Supplies Department has been issued a licence for the slope works." Mucuna vines usually grow on trees in the woodlands of tropical areas. Their leaves resemble large, curved pea pods with hamburger-shaped seeds. The vines produce dangling pendants of pungent, cream-coloured flowers and are pollinated by fruit bats. One hiker said the trees at this time last year were full of flowers during the blossoming season. But on a site visit to the slope yesterday, only two flowers were spotted. "It is easy to harm them but it is not easy for them to recover and grow back," she said. A Water Supplies Department spokesman said it was common for the department to conduct field visits and consult other departments before slope work. "Before the department began work on the … mentioned slope, we had conducted on-site tree assessments and consulted the relevant departments in accordance with guidelines on tree transplanting during construction works," he said.