Crayfish cages cause environmental problems in Lake Vättern

Crayfish cages that have worn out can remain for years and trap aquatic animals.
The County Administrative Board now urges those who are going out to fish for crayfish on Lake Vättern to check their equipment.
– It’s an environmental problem, says fisheries consultant David Solstorm at the County Administrative Board in Jönköping.

On the last Friday in August, public crayfish fishing begins in Lake Vättern. Before that, the county administration appeals to those who are going out to fish for crayfish to check their equipment a little extra to prevent cages from wearing out and drifting out into deep water, where they cannot be retrieved.

– The big problem is that the cages continue to catch crayfish and fish, says fisheries consultant David Solstorm. It can happen over a very long time as new aquatic animals enter the cages after the ones that entered first have died. It is quite a big environmental problem.

The sink that is missing probable cause

The County Administrative Board has dredged in Lake Vättern and found lots of abandoned crayfish cages on the bottom. There can be many reasons why cages wear out, but David Solstorm sees a pattern that can easily be avoided.

– Of the cages we got up, we see that an overwhelming majority lack the sink. When the cages do not have a sink, they can roll away and end up anywhere in the lake. The risk is also very high that the float will implode if the cage drags it out into deep water and then it will be very difficult for the owner to find the cage again, says David Solstorm.