Many of us have done it or seen someone do it. Sometimes, seeing the lush life below the waves is not enough for our own consumption — we want to capture it to share with others over morning tea, wine tinged dinners, or random conversations inbetween. So out comes the camera (or mobile phone) and snap! A photo is taken before the moment is gone. While the underwater kit some photographers haul around is impressive, it turns out that even a simple phone snapping a picture can help form part of a growing scientific record.
Across the Western Indian Ocean, scientists have long faced a familiar problem that plagues researchers in all other parts of the world: the ocean is vast, expensive to survey and unevenly studied. Some regions are heavily sampled while others remain almost blank on the map. And Mozambique sits right in the middle of this challenge; while biologically rich, it is historically under-documented, especially for sharks and rays. In recent years, however, citizen science has begun to shift that picture… literally, in this case. Platforms like iNaturalist allow divers, fishers and coastal residents to upload observations that are later verified by a global community of users. The result is a continuously growing dataset that fills gaps traditional surveys struggle to reach.
Using 408 observations collected between 2007 and 2025, researchers documented 44 elasmobranch species in Mozambique, representing roughly one third of all species previously known from the country. Rays dominated the dataset, particularly from families like Dasyatidae and Mobulidae, while sharks were mostly represented by Carcharhinidae and Rhincodontidae. Some species appeared frequently and predictably, like whale sharks and certain stingrays, while others surfaced only once or twice, offering rare glimpses into species that are otherwise difficult to study in the wild. But what stands out is not just what was recorded, but where: most observations came from southern Mozambique, particularly Inhambane and Maputo (whereas central and northern regions remained comparatively quiet). Why the difference? It likely reflects where people are diving, photographing and sharing their observations. Like many citizen science datasets, the data is influenced by human activity and accessibility. For example, these records were far from evenly distributed across time and space; observation numbers rose dramatically after 2019, mirroring broader trends in technology access, tourism growth and participation in biodiversity reporting platforms. This makes it difficult to fully disentangle biological patterns from observation effort. Even so, the spatial clustering of records aligned strongly with Important Shark and Ray Areas, suggesting that citizen observations are often happening in biologically meaningful places even if unintentionally so. And when the observations were compared to Marine Protected Areas, it was found that only a small portion of records fell within formally protected zones, even though many species recorded are under threat. In fact, 71 percent of all observed species were classified as threatened on the IUCN Red List, with a large share listed as endangered or vulnerable.
So, on one hand, citizen science is documenting species of high conservation concern. On the other, it is showing a mismatch between where biodiversity is observed and where legal protection is strongest. Which begs the question: are we still missing key regions that deserve attention?
Many often wonder how reliable this kind of data is when it comes to informing conservation decisions, and the dataset revealed that 82 percent of observations were classified as research grade, meaning they had community verification and sufficient metadata! While misidentifications still occur, especially in less verified entries, the overall reliability supports the use of these data in scientific contexts. This does not mean citizen science replaces traditional surveys — it’s a complementary tool that can be used to help show researchers trends over time, highlight rare encounters and even signal shifts in species distributions before formal surveys detect them. Ultimately, citizen science work like this continues to show that biodiversity monitoring is no longer confined to research vessels and long-term surveys alone. It is happening every day in dive logs, smartphone photos and even in data-limited regions like Mozambique. And thanks to those many eyes under the waves working together (unknowingly) in the name of science, conservation can be informed by a wider network of observers, each contributing small pieces to a much larger ecological puzzle! The challenge now is ensuring that these pieces are interpreted carefully, validated rigorously and used to strengthen, not replace, the deeper scientific work still needed to understand and protect ocean life.
