Seagrass surveys in the southern Rakhine coastal region, Myanmar: biodiversity, distribution and coverage

Abstract

Seagrass surveys were conducted at 9 study sites, in the southern Rakhine Coastal Region, to assess the species diversity, percent cover and extent of seagrasses for the better understanding of the current status and suitability of seagrass meadows for MPA designation. Among 9 study sites, except for Ma Gyi and Pho Htaung, the remaining 7 sites such as Tharthanar Dauk, Ngwe Saung, Wet Thay, Baw Di, Chan Pyin, Yay Myet Taung and Gyaing Kauk were newly recorded sites in the present surveys. There are two types of seagrass habitats: 1) intertidal habitats, mainly in shallow rock-pools at Baw Di and Yay Myet Taung; and 2) predominantly subtidal habitats at the remaining study sites. In the present surveys, a total of 10 species of seagrasses, namely Syringodiumisoetifolium, Cymodoceaserrulata, C. rotundata, Haloduleuninervis, H. pinifolia, Enhalusacoroides, Thalassiahemprichii, Halophilabeccarii, H. decipiensand H. major had been recorded. Among these, only one, Halophilabeccarii is was listed as Vulnerable on the IUCN RedList, while all other species were listed as Least Concern. Halophilabeccarii was only recorded at Pho Htaung. Halodulepinifolia was the most commonly observed species which was found in the remaining eight study sites. Pho Htaung, with the highest number of species (10 species) and coverage (66.9%), and as the only site to contain the Vulnerable Halophilabeccarii, should be assigned to a Marine Protected Area (MPA), as well as along with Ma Gyi and Chan Pyin given their high species diversity and coverage.