"It's an omnivore. It is usually said that it kills more than it eats. It can change the whole society underwater, says water ecologist Linnéa Carlzon at the County Administrative Board of Östergötland.
That the small crustacean was discovered was a bit of a coincidence. An inventory of benthic fauna made the unwelcome find. At Sverkerskapellet north of Hästholmen and outside Gränna, large quantities of larger predatory wagtails were found.
Greater predatory wagtail.
Unclear how it got to Lake Vättern
During week 19, several county administrative boards around Lake Vättern are working to inventory how much the marl has spread.
The origin of the larger predatory wagtail can be traced to the Caspian Sea and the Black Sea. How it got to Lake Vättern has not been investigated, but one suspicion is that it accompanied boats or gear that was previously in areas where the animal occurs.
In the video above, we follow Linnéa Carlzon on the inventory of the new invasive species.