A special find by ecologists Stijn Nollen, Atze van der Groot and Koen Wonders. They have now also recorded the stone marten in North. The small predator has been seen more often in the city, but never before in Noord. “They don’t swim, so we wonder, how did it get there?”

“The IJ is actually a barrier that has never been seen in Noord,” says Nollen. Together with Van der Groot and Wonders, he installed special cameras in Noord. “We are very surprised, especially because I told Atze that it was really not possible.” But Van der Groot was hopeful: “You never really know for sure what is alive and what isn’t, so I said we couldn’t rule it out. The first camera we checked, it was there,” he laughs.

The boys are excited about their scoop. “That video is super nice, especially the one that he plays with a mouse.” Nollen imitates the stone marten. “And that he comes to the camera like that, bowling. Wonderful.”

How so?

The two ecologists have different problems about how the marten got to Noord. The fact that the marten came via, say, North Holland, arose because the stone marten was last seen there eight years ago.

A different route via the IJ is therefore more logical. “You have the Oranjesluizen,” says Nollen, “of the IJtunnel.” Van der Groot joins in: “It was quiet with corona, so maybe it crawled through the tunnel without being run over.” Another option is that the animal has been hitchhiked with a car. “They like to crawl under bonnets, so maybe he drove along on the IJ,” says Van der Groot. Nollen laughs: “Then someone has unknowingly transported a marten under his hood.”

That the marten is in Amsterdam, that nature in the city is doing well. Nollen: “There are enough resting places in the city and there is enough food for them.”

German cars

However, probably not everyone is happy if the marten starts to reproduce more and more in the area. Martens find good nesting spots in attics and cavity walls. “They then take their prey into the wall and that can start to stink at a certain point,” the ecologists say. In addition, cables under the hoods are sometimes broken. Rumor has it that they mainly target German cars. “That would come with that cars use fish oil in the cables,” says Nollen.