Mangroves are defined as plants, such as trees, shrubs, palms and ferns, growing within the inter-tidal region of coastal and estuarine environments throughout the tropical and sub-tropical areas of the world (author year). Mangroves can also include the plants, the associated forest communities, and the abiotic factors, which form the mangrove ecosystem (Figure 2); for instance, the term ‘mangrove’ can be used as an adjective, i.e. ‘mangrove tree’ or ‘mangrove fauna’.

Sometimes the term ‘mangal’ is used interchangeably with ‘mangrove’ to refer to the biological components. McNae (1968), however, proposed that mangal should only refer to the forest community, while mangroves refer to the individual plant species.

Langkawi is an archipelago of 104 islands located at 6o21’N; 99o48’E to the north of the straits of Malacca. The total area of the archipelago is 47,848 ha and it is part of the state of Kedah in peninsular Malaysia. Langkawi is an archipelago of 104 pristine tropical islands. Only three islands are populated: the main Langkawi Island, Pulau Tuba and Pulau Dayang Bunting.

The topography of Langkawi is mainly flat to mountainous, rising to 881 m, which is the highest peak at Gunung Raya. Langkawi experiences dry season lasting two to three months between December and March, which influences the flora to have an affinity to those in Burma and Thailand. Lowland tropical rainforest in Southeast Asia is divided into two: evergreen lowland rainforest, which covers most of the floristic Malesian region, and the lowland deciduous rainforest, covering partly the Malesian region, Indochina and north-east Australia (Whitmore 1984).