House, Jennifer E; Magno, Xisto; Monteiro, Jose; Lopes, Julio; de Araujo, Simão; Mendes, R; Gomes, Jemima; Joaquim, Dina; Piludu, Nicola; McKenzie, Len J (2020): Seagrass community data derived from field surveys at Atauro Island and north coast Timor-Leste, conducted April 2017 to June 2018 [dataset]. PANGAEA, https://doi.org/10.1594/PANGAEA.912824

The Democratic Republic of Timor-Leste, the first new sovereign state of the 21st century, is located in the Lesser Sunda Islands archipelago of Southeast Asia, occupying half the island of Timor. Situated in the south-eastern boundary of the Wallacea biogeographical region and within the Coral Triangle, Timor-Leste's marine habitats support a high diversity of marine plants and animals that provide critical resources for coastal communities and also species of conservation concern, including dugongs and marine turtles. However, until recently, efforts to map marine habitats have been limited to broad-scale remote assessments. Providing detailed field validation of marine benthic habitats is critical knowledge required to identify priority areas for conservation of dugongs and seagrasses. Seagrass meadows on selected fringing reefs of Atauro Island and northern Timor-Leste (Tibar Bay and Com), were assessed between the 05 April 2017 and 27 June 2018. Observers walked or free-dived at survey points positioned approximately 5¬-10 m apart along a series of transects orientated perpendicular to the shoreline. Visual estimates of above-ground seagrass percent cover, macroalgae percent cover and substrate type were recorded at each survey point. A differential handheld global positioning system (GPS) was used to locate each survey point (accuracy ±3m). A total of 464 benthic survey points were examined. Seagrass community data was derived by haphazardly placing 1 or 3 quadrats (50cm x50cm) at each survey point. Seagrass percent cover was determined by estimating the total percentage of each quadrat occupied by seagrass leaves, to the closest 10%. Seagrass species present were identified and the composition of the total percentage cover estimated, using globally standardised Seagrass-Watch protocols. Data are presented as the average of the quadrats at each point. The resulting seagrass and benthic cover data of each survey point was linked to GPS coordinates, saved as an ArcMap point shapefile and projected to Universal Transverse Mercator WGS84 Zone 51 South