Rare Whale Sharks Monitored by Flickr and YouTube

Citizen scientists may have their chance to help some of the largest ocean-going creatures: whale sharks. Researchers are using the photos from people on vacation to help track the movements of these giant, endangered sharks living in the waters of the Indian Ocean.

The whale shark is the largest fish in the sea, reaching lengths of 40 feet or more. Although its size is massive, it prefers to eat plankton which it scoops up while filter-feeding. The shark prefers warm waters, and populates almost all tropical seas. It's also known to migrate every spring to the continental shelf of the central west coast of Australia. Unfortunately, the population size of these gentle giants is shrinking.

The new study, led by Tim Davies from Imperial College London, is the first to show that publically sourced photographs are viable for the use in conservation work. He and his team compared results using tourist images with results based on surveys by marine researchers specifically aimed at tracking the sharks. They looked a hundreds of images taken by the public, many of which were downloaded from image-sharing sites such as Flickr and YouTube. In order for a shark to be clearly identified, though, the photograph had to capture the distinctive pattern of spots located directly behind the gills of the shark.

More often than not, though, the researchers could identify the shark in the public-sourced photographs--about 85 percent of cases. Photographs taken by researchers, in contrast, allowed whale sharks to be identified 100 percent of the time.

Since tourists that scuba dive and snorkel in the Maldives frequently take underwater pictures of the whale shark, this new study could lead to a new way to track these gentle giants. Since the conservation status of the whale shark is uncertain, using these additional photographs could allow scientists to better estimate population numbers.

This isn't the first time that scientists have employed the public for monitoring species, though. The Christmas Bird Count, which occurs every year, uses hundreds of citizens across the U.S. to learn population estimates of migratory birds. Now, it seems that whale sharks will join other species that are currently being monitored by the public.