Hedeland Nature Park in Hedehusene near Roskilde is struggling to deal with what appears to be the contents of someone’s fish tank.
The Carolina fanwort – a sub-tropical plant originating in northeast and southeast America, which is a favourite of many a home aquarium owner – has turned up in two lakes, Fiskesø and Hundesø, in the national park.
It is believed the plant has been spread through someone dumping water from their aquarium, reports TV2 Lorry.
In order to minimise the chance of the plant spreading, the Miljøstyrelsen environmental authority has recommended the lakes be closed off.
Hair of the dog
The plant spreads when small pieces get caught up in fishing equipment, a dog’s coat or the legs of a horse etc – so dogs and horses will not be allowed to use the lake whilst Miljøstyrelsen cleans it up.
As well as being very easily spread, Carolina fanwort is regarded as a pest because it displaces the local flora.
According to a post on the website of the local fishing club Hedeland Fiskesø: “The Miljøstyrelsen’s biologists are extremely worried that the plant will spread to other lakes, so the lake will have to be cleaned, which means draining it.”
There is also a ban on fishing until further notice.