"A culling order has been issued for 13 farms," Tuija Gadd, head of the virology unit at the Finnish Food Authority, told AFP. "Culling has already been completed on 10 farms."
H5N1 bird flu outbreaks in seagulls were reported in June and the first cases of infected fur farm animals were detected in Finland in July.
Finnish authorities decided in early August to cull fur animals on all farms with infections, and the number of culls has steadily risen since.
Since late 2021, Europe has been gripped by its worst-ever outbreak of bird flu, while North and South America have also experienced severe outbreaks.
The World Health Organization warned in July that the surge in bird flu outbreaks among mammals could help the virus to spread more easily among humans.
There are around 400 fur farms in Finland with an estimated 1.3 million fur animals, Gadd said.
The bird flu outbreaks have reinvigorated calls to ban the industry in the Nordic country, Europe's leading producer of certified fox fur with nearly a million pelts produced annually.
During the Covid-19 pandemic, France, the Netherlands and Estonia introduced new bans, while Denmark ordered a cull of its entire farmed mink population after Covid outbreaks.
Gadd believed that the outbreaks on fur farms seem to be "calming down," as seagulls are already starting their migration south.