The researchers used CUREE (the Curious Underwater Robot for Ecosystem Exploration), a robotic vehicle developed as a part of the WHOI Reef Solutions Initiative, and combined CUREE’s cameras, hydrophones, and powerful on-board computers to analyze audio and visual signals in real-time, enabling it to autonomously identify areas of higher biological activity at unprecedented resolution. Their work combines different types of observations—direct (mapping audio and visual detection of animals) and indirect (what can be inferred from environmental soundscapes or behavior of sentinel species)—to identify where biological hotspots are most likely to be located. The system represents a breakthrough in the ability to identify, map, and monitor the fine-scale structure of reef biodiversity, a key part of understanding reef health and resilience. “We know that biodiversity on reefs isn’t distributed uniformly,” said Seth McCammon, a WHOI roboticist and lead author of the study. “But until now we haven’t really been able to reliably quantify that by finding these patchy hotspots, mapping them at the centimeter scale, and measuring just how active they really are. Developing this capability is going to be critical to helping biologists get a deeper understanding of reef ecology moving forward.” Coral reefs, which occupy less than 0.01% of the ocean, yet support roughly one quarter of all marine species, are under mounting stress from warming ocean water, disease, overfishing, and coastal development. This biodiversity clusters in localized hotspots—areas of intense biological activity that are critical for feeding, shelter, and reproduction. By resolving biodiversity patterns at sub-meter scales and linking them to habitat features such as reef structure, scientists will be better positioned to understand the processes that sustain reef ecosystems. Unlike traditional reef surveys conducted by trained divers, which are costly, limited in coverage, and potentially hazardous, CUREE can operate autonomously for hours at a time, precisely localize