Healthy coral reefs are kaleidoscopic underwater worlds that are vital to the survival of no less than a quarter of all species in the ocean. But these colorful habitats are changing fast as the threats of warming seas, overfishing and pollution jeopardize their continued existence.
Understanding how corals are responding to these threats is essential to securing their future. One of the new tools that has the potential to help researchers keep pace with all this change and guide coral conservation is called large-area imaging.
This technology uses software to stitch together overlapping underwater images to create photorealistic 3D models of entire reefs. By creating these 3D models at different points in time, scientists can quantify minute but important changes, like coral growth, that are difficult to measure in the field.
Divers swim in a gridded pattern over a coral reef, collecting imagery that covers multiple angles of the seafloor. This imagery can be stitched together to generate 3D models of the reef, a type of technology called large-area imagery. (Image credit: The 100 Island Challenge)
The potential applications of large-area imaging to coral conservation abound, but Orion McCarthy, a Ph.D. candidate at UC San Diego’s Scripps Institution of Oceanography, observed that this technology was mainly being used to answer academic questions by scientists from well-funded universities in relatively wealthy countries. In hopes of charting a course for using large-area imaging for applied coral conservation and to improve access to the technology, McCarthy and Scripps Oceanography researchers Kanisha Contractor, Clinton Edwards, and Stuart Sandin conducted a new study published in the journal Conservation Biology.
“We want to ensure that access to large-area imaging is equitable so that coral reef scientists and conservation managers from around the world can experience the benefits this new technology has to offer,” said McCarthy, whose research is funded by the National Science Foundation. “More equitable access has the power to improve coral reef conservation outcomes.”
The study reviewed scientific literature to establish how large-area imaging has been used to date. It found that the technology has mostly been used to answer theoretical ecological questions and less to inform conservation despite a large number of potential applications, such as tracking the fate of coral restoration projects.
Next, McCarthy and his co-authors identified barriers to wider adoption of the technology, especially for researchers in less-wealthy countries and conservation nonprofits with limited funds. The biggest barriers to wider usage of large-area imaging identified in the study were equipment costs, technical expertise or training, data storage, and sufficient staffing.
Based on feedback from current and new users of large-area imagery, the study authors developed a series of recommendations for how to make access to this potentially transformative technology more equitable.
The authors’ broadest recommendation is to use large-area imaging for conservation where new tools are needed to help coral reefs survive in the face of climate change and other threats. More specifically, the study’s recommendations seek to target the barriers identified earlier in the study and include developing training resources, creating partnerships for data storage, and developing new tools to make it easier to extract useful data from the resulting 3D models.
“The majority of the world’s coral reefs are in the tropics, but many of the scientists who study these reefs are from other, often wealthier, countries,” said McCarthy. “If we can successfully democratize powerful technologies like large-area imaging, I’m hopeful that this can help empower folks in developing countries to study their own reefs and answer questions that are hugely important for coral reef conservation.”
The next step for this research, according to McCarthy, is for the team to take one of their own recommendations and create a user guide for large-area imaging that will answer common questions and establish a standard methodology for creating beautiful 3D models and useful data.
