A study of bimonthly variations in community structure of macrobenthos in the intertidal zone was carried out in Kan Maw Island and adjacent areas of Myeik Archipelago during the low tide duration. This research was conducted at eight stations around Kan Maw Island from May 2017 to February 2019. For each station, three replicates were taken with a quadrant 30x30cm (to a depth of 30cm) along a transect and sieved with a 1mm mesh size. The macrobenthic biodiversity was represented by 73 species belonging to 42 families under eight major phyla viz. Mollusca (53.4%), Arthropoda (20.6%), Brachiopoda (1.4%), Echinodermata (1.4%), Annelida (19.2%), Hemichordata (1.4%), Coelenterata (1.4%), and Nemertea (1.4%). Three metrics were utilized to estimate diversity: Shannon-Weaver's diversity index (H'), evenness index (E') and Margalef's richness (D) using univariate analysis. The relationship of abundance and diversity indices (except richness, D) were positively correlated with sediment (silt and clay) but temperature, salinity and sand had a negative correlation during the study period. In addition, macrobenthic groups (except Mollusca, Arthropoda and Annelida) were significantly effected by salinity, temperature and pH, but not by sand (except Cnidaria), clay (except Annelida) and silt (except Cnidaria, Annelida, Mollusca, and Arthropoda).

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.

Sea grass surveys were conducted in Lampi Island (Marine National Park), Taninthayi Region from 7th Novemver to 9th November 2018. A total of 5 species of sea grasses, namely Cymodocea rotundata Ehrenberg et Hemprich ex Ascherson, Halodule uninervis (Forsskal) Ascherson, H. pinifolia (Miki) den Hartog, Thalassia hemprichii (Ehrenberg) Ascherson, Halophila ovalis(R. Brown) Hooker f. were recorded from the survey sites. Thalassia hemprichii represented as a dominant species along the 3 cross-transects in Wa Kyun Island but not the other 2 study sites, Bo Cho Island and Nyaung Pin Aw on which Cymodocea rotudata predominantly occurred. A total of mean coverage of sea grasses were higher in Bo Cho Island (62.64%) than the other 2 study sites, Wa kyun (43.47%) and Nyaung Pin Aw (54.5%). Due to the dominance of the species of Thalassia hemprichii with thick rhizomes, the biomass of the below ground of the seagrasses in Wa Kyun Island (70.43 gm dry.wt m‾²) was much more higher than those of the other 2 study sites, Bo Cho Island (38.49gm dry.wtm‾²) and Nyaung Pin Aw (59.63gm dry.wtm‾²).