Administrator Anton Rikstad with the county administration in the central Nord-Trøndelag region called individuals suspected of carrying out the practice “pike mafia”.
“I fear there is a gang fanatically obsessed with fishing large pike. That's why I call them the ‘pike mafia'. I don't know where or who they are, but there is something suspicious about it,” Rikstad told broadcaster NRK.
The carnivorous fish has been illegally introduced into the water at a number of places in Norway, according to the report. After two such fish were caught in the Hovdalsvatnet lake - which provides drinking water for the local Frosta municipality - last week, Rikstad decided to take action.
Releasing fish out of their natural habitats in this way is an illegal activity, he said.
“This incident joins the ranks of a series of illegal releases of foreign species during the last few years. That includes fish, plants and animals. It's illegal and we consider it to be environmental crime. It's almost always bad for the environment,” Rikstad said.
Pike fish have been spread around Norway for hundreds of years, for food, sport and even as an act of revenge against neighbours, according to NRK's report.
“When pike fish were released in Steinkjer a few years ago, the were rumours about trying to create a trophy fish. It's popular to catch large fish, but we do not like the spread of this at all,” Rikstad added.
Vidar Sunde, coordinator for nature and the environment in the Trøndelag police district, confirmed that police are taking the issue seriously and that the illegal introduction of species into new habitats can be punished by up to three years' imprisonment.
No-one has previously been convicted for an offence of this type, the police officer said.
“If the release took place a long time ago then statutory limitations also become relevant. In many cases, too much time has passed since the criminal offence took place,” he said.
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