Environmental group Green Power released the latest results of Butterfly Survey of six butterfly hotspots. The tally is 184 butterfly species, about 70% of Hong Kong's total, including 58 "Very Rare" and "Rare" species. The top three survey sites with the most butterfly species are Luk Keng in North District, San Tau in Tung Chung and Lung Kwu Tan in Tuen Mun with 154, 135 and 128 species registered respectively.
Matthew Sin, Chief Environmental Affairs Manager of Green Power, reported that 154 butterfly species were recorded at Luk Keng where butterfly diversity had been growing for three consecutive years. It is a record high for an individual hotspot since 2008.
Matthew Sin said the remoteness of Luk Keng, located close to Sha Tau Kok in the northeastern Hong Kong, allowed the place to preserve its natural ecological environment and prevented large-scale development. The place owes its biodiversity to the presence of a variety of natural habitats: freshwater wetlands, brackish wetlands, mangrove swamps, deserted fields, Fung Shui woods etc., which is conducive to the reproduction of different butterflies. Luk Keng was designated as one of the "Priority Sites for Enhanced Conservation" in 2004. Unfortunately, Matthew Sin revealed there was news of illegal dumping of construction waste on one hectare of wetlands in May. Similar incidents have happened before, which indicates failures of conservation policy and regulation measures. He recommended extending conservation to surrounding areas of designated wetlands in the "Priority Sites for Enhanced Conservation" and including Luk Keng in the Nature Conservation Management Agreement Scheme to protect its valuable ecosystem.
San Tau has the second most butterfly species in the latest butterfly count. Surveyors reported to Matthew Sin last month that copious amounts of trees - more than three hundred - flanking Tung O Ancient Trail at San Tau had been cut down. Authorities have been alerted. Among the felled trees are native species including Turn-in-the-wind (Mallotus paniculatus) and Yellow Cow Wood (Cratoxylum cochinchinense). The former provides food for the larvae of "Very Rare" Malayan (Megisba malaya) and the latter is the food source of various butterflies' larvae. Vegetation cover takes time to recover from the extensive felling, which is going to have long-term detrimental effect for the thriving of butterflies there.
Matthew Sin said illegal land filling or tree felling had been common in the countryside. He asked the authorities to mete out harsher punishment for offenders and order land rehabilitation by owners to discourage recidivism.
About Green Power's Butterfly Survey
The Butterfly Survey, launched in 2008, adjusts its survey sites each year depending on their conditions. The survey is conducted by "Butterfly Surveyors", who are citizens that have been trained and certified. It typically starts in June or July each year and continues until the following May or June, which allows for ongoing comparison of butterfly resources and environmental changes at different survey sites. The latest Butterfly Survey (2024 – 2025) was conducted by 245 butterfly surveyors across six sites.
