The Scottish SPCA has been contacted and are attending to provide assistance to the Swan located in Birnie and Gaddon Lochs.
It is unclear how the swan managed to get stuck in the line, however, local officers are reminding the public that it is illegal to fish in either of the reserves.
PC Ben Pacholek, Fife's Wildlife Crime Liaison Officer, said: “Whilst it is unclear where the swan has become tangled in the fishing line, I’d remind anyone attending Birnie and
Gaddon Lochs that fishing is not permitted on either of the reserves.
"Anyone fishing at the reserves is committing a criminal offence and could find themselves the subject of a report to the Procurator Fiscal."
Information on wildlife crime can be found via Police Scotland’s website.