Combining classical field surveys with innovative imaging and data technologies, marine scientists are monitoring coral reefs digitally to see how these populations of organisms now under extreme stress change with time.
Coral reef ecologists at Scripps Institution of Oceanography are using detailed photomosaics to collect data and study coral reefs around the world. To create this visual data for one reef, scientists led by Stuart Sandin and Jennifer Smith canvas thousands of square feet of reef, taking as many as 40,000 images that are then stitched together to create 3D photomosaics of a single reef.
During the data-gathering for each photomosaic, the scientists generally do three dives a day. The images come from Palmyra, where it took more than five full days of diving to collect the images for the sixteen plots used in a recent study. Back in the lab, a high-performance-computing system stitches together the thousands of individual images that make up each 3D mosaic. A custom software developed by a UC San Diego computer science graduate student then allows scientists to label, annotate and classify all the corals in each image. Then the final step is to extract the species information and analyze the image.
These 3D renderings allow scientists to virtually explore reefs in the lab, and are creating baselines where scientists can now track the growth year-to-year and measure increases or decline of individual colonies, and to study spatial and temporal relationships across the reef.
The data collected of the coral reefs is part of the 100 Island Challenge, the goal of which is to create a global perspective on how coral reefs are changing over time.
The 100 Island Challenge team is partnering with scientists and communities around the world to visit 100 different islands throughout the Pacific, where they will use these novel 3-D imaging techniques to capture every detail of the coral reef structure and ecology.