Divers around the world are carrying an extraordinary archive of marine biodiversity on their cameras and hard drives—and many may not realise just how important their photographs could be.
Valentin's sharpnose puffer (Jenny Huang /CC BY 2.0)
Every day, divers capture images of fish living naturally on coral reefs, over sandy bottoms, in kelp forests, estuaries, caves, and the open sea. These photographs are far more than souvenirs or artistic images. Increasingly, they are valuable scientific records, documenting marine biodiversity at a time when aquatic ecosystems are changing rapidly.
iNaturalist
One of the most important places where such observations can be shared is iNaturalist, the global citizen-science platform where people upload photographs of living organisms to help document biodiversity worldwide.
While birds, insects, mammals, flowers, fungi, reptiles and many other groups are widely represented on iNaturalist, fishes remain under-documented, along with most other aquatic plants and animals. Yet fish are among the most diverse vertebrate groups on Earth, occupying nearly every aquatic habitat imaginable.
Part of the reason is simple: photographing fish underwater requires specialised skills and equipment. Another reason is that many fish photographs uploaded online originate from fishing activities and are not identifiable in the photos. In many cases, fish appear out of water, piled together in a bucket, stressed, dying, or already dead. Some such images can certainly contribute to species records, but they cannot show fish as they truly are in their own environment.
Divers, however, are uniquely positioned to help fill this gap.
The importance of photos taken underwater
A diver’s photograph may document not only the species itself, but also colouration, habitat, behaviour, social interactions, cleaning symbioses, camouflage, courtship, spawning activity, juvenile stages, and species associations that are absent in fishermen's photographs.
In some cases, photographs taken casually during recreational dives may later become scientifically important. They may document unusual range extensions, rare animals, seasonal appearances, changes in abundance, or species present in locations where, in formal surveys, they are infrequent or absent.
As climate change, overfishing, habitat destruction, warming oceans, coral bleaching, and pollution continue to alter marine ecosystems, the need for biodiversity documentation has become increasingly urgent. Historical records are incomplete, especially underwater. Many marine species are declining before they have even been adequately documented.
This is where divers can make a real contribution.
Fish are still seen primarily as a resource
Unlike terrestrial wildlife, fish are still often viewed primarily as resources rather than as wild animals to be observed alive in their natural setting. Yet, fish are among the most evolutionarily ancient and biologically sophisticated vertebrates on Earth. Modern research increasingly reveals complex cognition, social behaviour, learning, memory, and problem-solving abilities in those species studied.
To see fishes underwater is to encounter not anonymous objects, but individual wild animals living in intricate environments and participating in dynamic ecological communities. Photographs that capture these animals in their own realm have immense value—scientifically, aesthetically, and ethically.
iNaturalist is easy to use
Uploading observations to iNaturalist is straightforward. A diver simply uploads a photograph and specifies the location and date. Other users then help identify the species. These observations thus become part of a vast, global biodiversity database used by naturalists, scientists, educators, conservationists, and researchers.
Importantly, underwater photographs allow various species of fish to be documented without handling or removing them from the water. Unlike fishing, divers' photos document and record aquatic life while minimising stress and disturbance to the animal.
The oceans remain far less documented than the land. Vast numbers of marine species, behaviours, and ecological interactions are still poorly known or completely unknown. Divers explore this hidden world every day.
Their photographs matter, and their observations are needed. Together, they will help provide an irreplaceable record of marine life during a time of profound environmental change. Just go to iNaturalist and follow the prompts to join and start uploading!
Ethologist Ila France Porcher, author of Yes, Fish Feel Pain, The True Nature of Sharks and six other books on wildlife behaviour, spent 15 years closely observing fish and shark behaviour in Tahiti, resulting in several scientific papers. Her writings are based on decades of first-hand observations of wildlife and focus on the individuality and intelligence of individuals, challenging traditional views of animal minds. Her work has been featured on Shark Week, in scientific discussions, conservation debates and international media for its unique blend of field observation, art and science.
