Sampling state and process variables on coral reefs

Community structure and size-frequency distribution of soft corals in a heavily disturbed reef system in northwestern Philippines

Soft corals in the Philippines have received little attention. In this study, community structure and size-frequency distribution of soft corals were assessed via quantitative surveys in a heavily disturbed reef system in northwestern Philippines. Relationships between selected environmental parameters and benthic components were also investigated. Results reveal that soft coral cover, density, and taxa richness were lowest at stations nearest a fish farming area, characterized by the poorest water quality. Differences in dominance of taxonomic groups may indicate differences in environmental preference or tolerance. Exposure to waves and water clarity were determined to have high correlations with the distribution of different taxa. Symmetrical size distributions of selected alcyoniids were indicative of healthy populations. However, the negative skewness of Lobophytum may indicate an eventual population decline caused by unfavorable environmental conditions. The study's findings suggest the need to conduct a detailed analysis of the different soft coral variables during coral reef surveys to improve data interpretations necessary for coral reef management in the Philippines.

Coral benchmarks in the center of biodiversity

There is an urgent need to quantify coral reef benchmarks that assess changes and recovery rates through time and serve as goals for management. Yet, few studies have identified benchmarks for hard coral cover and diversity in the center of marine diversity. In this study, we estimated coral cover and generic diversity benchmarks on the Tubbataha reefs, the largest and best-enforced no-take marine protected area in the Philippines. The shallow (2-6m) reef slopes of Tubbataha were monitored annually, from 2012 to 2015, using hierarchical sampling. Mean coral cover was 34% (σ±1.7) and generic diversity was 18 (σ±0.9) per 75m by 25m station. The southeastern leeward slopes supported on average 56% coral cover, whereas the northeastern windward slopes supported 30%, and the western slopes supported 18% coral cover. Generic diversity was more spatially homogeneous than coral cover.