Summit County Citizens Voice

Some whale shark migrations are still a mystery for marine biologists. Photo courtesy NOAA/ Quenton Dokken.

Mysterious giants still hold puzzles for researchers

By Summit Voice

FRISCO — Vacation snapshots from the Indian Ocean region may help biologists understand the life cycle and migration patter of whale sharks, according to a new report from Imperial College London.

Researchers led by Tim Davies compared tourist photos with scientific marine survey data, fining that the photographs from public sources are suitable for use in conservation work. Whale watchers can also help by uploading their images to the ECOCEAN whale shark identification library website (www.whaleshark.org).

In order for a shark to be clearly identified, any photograph must capture the distinctive pattern of spots located directly behind the gills. This unique marking serves as a “fingerprint,” which can then be scanned with a computer program to tell the animals apart.

“Globally, this outcome provides strong support for the scientific use of photographs taken by tourists for whale shark monitoring,” Davies said. “Hopefully, this will give whale shark research around the world confidence in using this source of free data. In the Maldives in particular, where whale shark tourism is well established and very useful for collecting data from throughout the archipelago, our results suggest that whale shark monitoring effort should be focused on collecting tourist photographs,” he added.

Tourists scuba diving and snorkelling in the Maldives frequently take underwater pictures of the spectacular and docile whale shark, often called the world’s largest fish. Conservationists have long hoped to use this photographic resource to help them trace the sharks’ life history, relationships and geographic distribution, although the value of these amateur snapshots has never been properly measured.

Tim Davies of Imperial’s Department of Life Sciences is the lead author on a study published in Wildlife Research, the first to examine how reliable photographs sourced from the public actually are. He and his team did this by comparing results using tourist images with results based on surveys by marine researchers specifically aiming to track the sharks.

In order for a shark to be clearly identified, any photograph must capture the distinctive pattern of spots located directly behind the gills. This unique marking serves as a ‘fingerprint’, which can then be scanned with a computer programme to tell the animals apart.

The study looked at hundreds of images taken by the public, of which many were downloaded from image-sharing websites such as Flickr and YouTube. Individual whale sharks could be successfully identified in 85 per cent of cases, surprisingly close to the 100 per cent identification possible in photographs taken by researchers.

For more information on Maldivian whale shark visit the Maldives Whale Shark Research Program website http://maldiveswhalesharkresearch.org.

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