Romer's Tree Frog is the smallest frog species in the territory that was first discovered by naturalist J.D. Romer in a cave on Lamma Island in 1952. After the cave collapsed in 1953, it was once thought that this rare species had gone extinct. Fortunately, later in the 1980s, scientists rediscovered the frog on four outlying islands in Hong Kong, including Lamma Island, Lantau Island, Chek Lap Kok and Po Toi Island.
Romer's Tree Frog mainly inhabits wooded areas in proximity to streams or other water sources, but can occasionally be found in some man-made ponds. Its brown body closely resembles the colour of fallen leaves, and there is a distinctive 'X' marking on its back with small warts scattered across. Although its digits are equipped with suction discs that aid climbing, it prefers staying close to the ground. With its well-camouflaged body along with the habit of hiding inside leaf piles and bushes, the frog can be extremely hard to spot with the naked eye.
The tree frog is a nocturnal species that preys on termites and other insects. Its breeding season is from March to September. During courtship, male tree frogs make 'di-di-di-' calls that sound very similar to cricket calls to attract the larger females. They generally choose to breed near the forest-bottom, in clear streams or static water with no fish to escape predation.
In the 1990s, the construction of Chek Lap Kok Airport put the tree frog's population at the site in peril. The authorities and experts, therefore, carried out a rescue operation and ex situ breeding programme to subsequently translocate the tree frogs to other locations in the wild for long-term monitoring. In view of the ecological and scientific importance of Romer's Tree Frog, one of its major habitats, Ngong Ping, was designated as a 'Site of Special Scientific Interest' in 1999, to recognise the conservation and research values of the site.
| Family | Rhacophoridae |
|---|---|
| Scientific Name | Liuixalus romeri |
| Adult Size | 1.5–2.5 cm in length |
| Habitat | Wooded areas near streams |
| IUCN Red List Status | Endangered |
