A southern right whale off the coast of Argentina. (Photo: REUTERS/Maximiliano Jonas)
It used to be that if you wanted to know how many whales were in the ocean, you had to get on a boat or a plane and count them. But now, scientists are using images from space to count whales digitally, with surprisingly accurate results.
According to a report published in the journal PLOS One, a new program that uses extremely high-resolution images from the WorldView-2 satellite can detect whales near the surface of the ocean. The program was tested by scientists from the British Antarctic Survey, who used it to count southern right whales in the Golfo Nuevo off Argentina. The program captured 89 per cent of the whales recorded by a manual survery at the same time — not perfect, but pretty impressive, given that each whale only takes up a pixel or two of the satellite's massive photos, and that the satellite itself is located 770 km above the earth.
"Our study is proof of principle," Peter Fretwell of the British Antarctic Survey told the BBC. "But as the resolution of the satellites increases and our image analysis improves, we should be able to monitor many more species and in other types of locations."
The WorldView-2 satellite is one of the most advanced earth observation units currently in use. It's able to take pictures with a resolution high enough to make out features as small as 50 cm.
And its not just science itself that stands to benefit from this technology — it's the scientists, too. Apparently, counting whales is a fairly dangerous endeavour, one that researchers would be happy to give up.
"Many marine mammal researchers have been killed flying in small planes while surveying whales," Vicky Rowntree, director of the Ocean Alliance's Southern Right Whale Program, told the BBC. "So my great desire is to get us out of small planes circling over whales and to be able to do it remotely."