How divers are revolutionizing fisheries data collection
Reef Environmental Education Foundation (REEF) has a long history of connecting the dive community to marine conservation. Through the Volunteer Fish Survey Project (VFSP), REEF has empowered divers to contribute valuable data for more than 30 years, transforming recreational dives into opportunities for scientific research and ecosystem protection.
Participating in the VFSP is fun, easy, and free. Often described as birdwatching but with fish, volunteers can do REEF surveys in all ocean waters on scuba or snorkel. Surveyors record all fish species they see (along with select invertebrates and algae in temperate waters) and keep track of how many of each species they see during the dive using abundance categories. Volunteers then submit their survey data through the REEF website.
With a growing network of more than 18,000 passionate volunteers, REEF has built the world’s largest marine life sightings database, encompassing more than 300,000 surveys and used in more than 130 scientific publications.
Today REEF is pushing the boundaries of citizen science. By integrating advancements in image-based technology, they’ve introduced two innovative projects — Size Matters: Innovative Length Estimates (SMILE) and Grouper Spotter. These initiatives aim to reshape fisheries science and marine monitoring by turning divers and snorkelers into skilled, nonextractive data collectors who document and preserve the natural behaviors and habitats of the species they study.
The following is an inside look at how these innovations are expanding the role of divers in conservation and how you can participate.
Fisheries Science with a SMILE
Measuring the sizes of fish in a population is a fundamental aspect of fisheries science that reveals critical details about growth rates, the arrival of young fish to a population, spawning potential (bigger females produce more eggs), and fishing impacts.
The usual traditional methods for measuring fish lengths involve capturing and handling fish, a process that can stress or injure fish. The SMILE project offers a groundbreaking alternative: a laser-based image-capture system that allows divers to measure fish with a simple camera shutter click.
SMILE equips divers with specially designed FishSense-Lite cameras with an integrated laser pointer for precise measurements. The setup is straightforward: Divers aim the laser at the side of a fish and snap a burst of photos, and an analysis driven by artificial intelligence (AI) extracts length measurements from the images.
The project focuses on 11 key species, including large groupers, snappers, hogfish, and parrotfish, and turns fish measurement into an underwater hunt where divers prowl the reefs for quarry to measure. The thrill of finding and capturing laser images of target fish instills excitement in any dive and has the extra benefit of generating critical data on species with high ecological and economic value.
SMILE came to life through a partnership with Scripps Institution of Oceanography and the University of California San Diego’s Engineers for Exploration (E4E) program, a collaborative initiative in which student engineers work alongside scientists to solve real-world problems. The current FishSense-Lite uses an Olympus TG-6 camera with a green laser, secured with a uniformly sized 3D-printed mount. The goal is to make the technology versatile and affordable. REEF and partners at Backscatter Underwater Video and Photo are currently working on the next generation of the tool, with a watertight, magnetic, rechargeable dual-laser system that is compatible with nearly any camera model.
REEF surveyors in the Florida Keys, throughout the Caribbean, and off Mexico’s Pacific coast have field-tested the imaging tools and project methods with great success. Adding SMILE to REEF’s arsenal of citizen science tools will enable scientists to paint a fuller picture of reef fish populations worldwide.
Previously, REEF’s citizen science data were useful for understanding where different types of fish were seen and in what numbers. When divers reported large numbers of fish species, however, it was impossible to know if it was a school of just-hatched juveniles or a large group of trophy-sized adults. With SMILE — and precise fish lengths paired with observational data on abundance — REEF volunteers are poised to supply valuable data to fisheries management and ecosystem assessments.
Diver feedback has been instrumental in refining the technology. Social scientists are developing a formal user survey to distribute before and after SMILE dives to increase engagement and improve the diver experience. REEF continues to seek divers to test SMILE in the Florida Keys and plans to expand the project to other regions soon.
“SMILE was another opportunity to combine my interest in diving and volunteering,” REEF volunteer Fred Hartner said about the experience. “The equipment provided an intriguing and different challenge.” Divers interested in learning more or supporting the project can contact smile@REEF.org for more information.
Grouper Spotter
While fish-length data are critical for understanding population dynamics, Grouper Spotter tackles another significant challenge: noninvasive identification and tracking of individual fish. This project focuses on groupers, a highly vulnerable species known for forming dense spawning aggregations that make them easy targets for fisheries.
Like the facial recognition software on your smartphone, Grouper Spotter uses AI to automate detection and identification, allowing divers to use cameras to document and track individual groupers based on their unique patterns.
Working alongside another nonprofit organization, Wild Me, REEF has adapted sophisticated AI and machine-learning algorithms to recognize and match individual groupers by their natural markings. This technology eliminates the need for traditional tagging methods involving scientists implanting visible markers on individual fish.
This noninvasive approach is invaluable for areas without resources for regular monitoring or invasive tagging practices, offering a low-cost, high-precision tool to support fisheries management. It also allows scientists to track individuals from threatened or endangered fish populations without the potential of harming them.
Nassau groupers have served as the pilot species for this project, thanks to their distinct barred patterns and the existing long-term data collected through REEF’s Grouper Moon Project, a conservation science partnership between REEF and the Cayman Islands Department of Environment. Scientists from Scripps Institution of Oceanography at the University of California San Diego and Oregon State University are collaborators on the project. The Grouper Moon Project has amassed tens of thousands of Nassau grouper images since 2002 from documenting individuals at the Cayman Islands spawning sites.
With this robust dataset, Grouper Spotter has successfully demonstrated that AI can identify individual fish. The data produced will allow scientists to track fish movements and analyze population metrics such as births, deaths, and even behavior (for example, are certain fish always found together?). When paired with length-measurement technology like the SMILE project, scientists can estimate the growth of individuals over time.
“With Grouper Spotter, we leverage the latest AI tools to capture data with remarkable richness and value,” said Brice Semmens, PhD, Scripps Oceanography Grouper Moon Project Lead. “And because Grouper Spotter has been built around citizen scientists and low-cost tools, the program will benefit threatened endangered or imperiled populations that are otherwise very data poor.”
The potential for Grouper Spotter extends beyond Nassau groupers. REEF recently began building training datasets that will expand the platform to other grouper species, including camouflage groupers (in collaboration with Ocean Blue Tree Foundation), Atlantic goliath groupers (in collaboration with the Florida Fish and Wildlife Conservation Commission), and potato cods (in collaboration with Wildlife and Ecological Investments). In July 2023, Ocean Blue Tree Foundation sponsored a dive expedition to a camouflage grouper spawning aggregation site in Fakarava, French Polynesia, where volunteer divers collected images to establish a foundational dataset for this threatened species.
REEF aims to build a worldwide network of divers to support Grouper Spotter. These citizen scientists will ultimately gather diverse image datasets across locations and seasons. For more information on Grouper Spotter and how to support the project, contact grouperspotter@REEF.org.
Divers as Conservation Champions
SMILE and Grouper Spotter are expanding the role of ocean citizen science and enriching the dive experience. Divers who participate make tangible contributions to marine science and become active stewards of the ecosystems they explore. This shift from passive observation to purposeful data collection fosters deeper connections between divers and the ocean.
For REEF, these projects are a testament to the transformative potential of citizen science paired with cutting-edge technology. The knowledge that citizen scientists generate helps support everything from local fishery regulations to international conservation initiatives, so divers are truly providing a foundation for protecting marine biodiversity. They are also part of an effort that is growing more global, connecting divers worldwide in a commitment to preserving the ocean for future generations.For more information on these initiatives, visit REEF.org.
Jelajahi Lebih Lanjut
Watch this video to learn more about SMILE.
© Penyelam Siaga – Q1 2025