Researchers can sometimes be in the right place at the right time in the Indian Ocean to snap photos of whale sharks, but not often enough to collect enough data on this endangered species. This is why they are turning to tourist photos to help.
Scuba divers and snorkelers in the Maldive Islands, an island nation in the Indian Ocean, are often equipped with underwater photography gear to capture images on their dives and excursions. Many of them have been lucky to find and photograph the whale shark, the largest recorded fish.
Whale sharks can grow to lengths of 40 feet or more (around the size of an average school bus) and are generally meek, preferring tiny plants and plankton that they scoop up while swimming with their large mouths open. This method is called “filter feeding”, simply passively filtering whatever happens into its path as it swims. Because the whale shark is so docile, many tourists have been able to take clear, close pictures of it as it swims.
Conservationists have long tried to collect data about this shark, currently labeled with the protection status “vulnerable species”, including learning more about the history of the giant fish, its relationships, and specific geographic distribution to help protect them. One step from being labeled endangered, the whale shark is still hunted in parts of Asia.
Tim Davies of Imperial’s Department of Life Sciences, is studying with a team to determine the value of tourist photographs of the whale shark based on surveys by researchers tracking the sharks. The first step is the ability to definitely identify the shark in each photograph. In order to establish identification, the photo must include the pattern of spots directly behind the whale shark’s gills. These are its signature marking and most effective identifying pattern. Without the pattern, the fish cannot be conclusively identified. A computer program is used to scan the patterns and confirm identification of the whale shark.
Davies’ team studied hundreds of photos posted on the Internet from sites such as Flickr and YouTube. They were quite surprised to find that the public had accurately identified 85% of the tagged whale shark photos. While researchers’ images are accurate 100% of the time, this is still much higher than was anticipated. The team is encouraged and feels that the free data posted by tourists will provide researchers with important data for whale shark monitoring.
By monitoring publically available images, research will be bolstered and results will be more complete. The images will assist in providing a clearer picture of the population and conservation status of the whale shark, especially in the Maldives Islands. Ongoing monitoring of public images will help researchers to understand if the population of the rare fish is declining or remaining stable. This data has eluded scientists as sightings of the whale shark can be rare.
The results of this study indicate that future whale shark monitoring efforts will include collecting photographs from tourists. Vacationers will be doing their bit to help science!
