The extent and speed of recent changes in reef coral abundances due to ocean warming and human impacts require more widespread capability to map and measure these changes, especially in countries like the Philippines. We present “C30”, a simple, rapid, scientifically valid, and low-cost method for skin divers or freedivers to take random photo-quadrat images within predefined stations on the upper reef slope. C30 yields coral cover data similar to those collected using the more intensive C5 method and can be as powerful in detecting small differences in reef cover. Less time is also needed for training personnel and sampling. However, more photo-quadrat images, better cameras, and closer collaboration with local scientists are required if higher precision data and estimates of coral diversity are needed from C30. C30 is a valuable tool for participatory, community-based citizen science monitoring of coral reefs.

由于海洋变暖和人类影响，最近珊瑚礁丰度变化的范围和速度需要更广泛的能力来绘制和测量这些变化，尤其是在菲律宾等国家。我们提出了“C30”，这是一种简单、快速、科学有效且成本低的方法，可供皮肤潜水员或自由潜水员在上礁斜坡的预定义站内随机拍摄方形图像。C30 产生的珊瑚覆盖数据类似于使用更密集的 C5 方法收集的数据，并且在检测珊瑚礁覆盖的微小差异方面同样强大。培训人员和取样所需的时间也更少。然而，如果需要来自 C30 的更高精度的数据和珊瑚多样性估计，则需要更多的方形照片、更好的相机以及与当地科学家更密切的合作。