In northern Bohuslän, bathers must beware.

This is where the giant Japanese oyster, with its sharp edges, has spread.

- They grow up on top of each other, and dig themselves into the sand, says Joakim Ulvhammar, who is a camping entrepreneur in Saltvik.

To solve the problem, it has been suggested that the public should be allowed to pick the oysters.

But according to oyster diver Lotta Klemming, this is a bad idea.

- Then there is a risk that you also pick other oysters, she says.

Listen more to the clip above.