Last time the population was surveyed, there were only around 500 Baltic Sea porpoises left. Now the acutely threatened species is to be counted again.
Since the porpoises in the Baltic Sea are so few, it is not possible to estimate the number using traditional methods such as observing them from planes or boats. Instead, researchers will use specially developed detectors to locate the porpoises via their clicks.
In total, around 200 detectors will be placed, with about half of them in Swedish waters.
"Thanks to this, we will be able to make a more accurate estimate of how many Baltic Sea porpoises there are," says Julia Carlström, researcher at the Natural History Museum, in a press release.
The Baltic Sea porpoises were last surveyed between 2011 and 2013 and were estimated to be only around 500 individuals. The new survey will take place from 1 July this year to 30 June 2025.
