A New Method For Counting Whales From Space
Scientists using a very high-resolution satellite and image-processing software, demonstrated a new method for counting the whales from space. The set-up automatically detected the huge mammals at or near the ocean surface.
According to scientists, the automated system was able to detect 90% of the whales out of total pinpointed manually. The developed method might revolutionize the way whale populations are estimated.
Up until now, the count was done manually from ship or plane and was limited to regions. However, an automated satellites search will be able to cover the much larger area of the ocean further minimizing the cost.
"Our study is a proof of principle," said Peter Fretwell from the British Antarctic Survey, according to 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 location.It should be possible to do total population counts and in the future track the trajectory of those populations."
A 113-sq-km segment of the Golfo Nuevo on the Peninsula Valdes was selected for testing the accuracy of the automated system. Despite their larger sizes, whales only took up few pixels in the satellite picture.
"In this type of automated analysis you have to balance two types of errors - errors where you miss whales, and errors where you misidentify whales. If you push too hard one way, like trying to catch all the whales, you'll increase the number of false positives. With our 90%, we had almost no misidentifications," researchers explained in the press release.
Other experts believed the new method will be huge boon to field of research relating to whales.
"It's going to be absolutely amazing. The other dimension of it is that many marine mammal researchers have been killed flying in small planes while surveying whales. So my great desire is to get us out of small planes circling over whales and to be able to do it remotely. Satellite data is wonderful," said Prof Vicky Rowntree from the University of Utah and the director of the Ocean Alliance's Southern Right Whale Program, according to BBC.
The test count was conducted in the Golf Nuevo, Argentina and was reported in the journal Plos One.