How Do You Measure the World’s Largest Fish? Lasers!
Study lead author Chris Rohner swims with a whale shark.
It can be difficult to get basic measurement information from the whale shark, the world's largest known fish - you can't exactly swim up to it with a measuring tape.
Researchers from Australia's Marine Megafauna Foundation are using a new measuring technique called "laser photogrammetry" that's giving them more accurate data than ever before.
According to lead researcher Chris A. Rohner, laser photogrammetry involves "projecting laser pointers onto the flank of the shark while taking a photo to provide a scale bar". His team deployed the method on live, free-swimming sharks in Mozambique as part of a new study recently published in PeerJ.
The new method could prove integral in helping conservationists protect the threatened whale shark. Rohner notes that the majority of the whale sharks observed by his team are juvenile males; there have been few sightings of newborns, mature sharks and females. Laser photogrammetry could significantly improve the scientific community's understanding of whale shark demographics and contribute to conservation efforts.