Swine fever controls disrupt wildlife crossings on Finland’s eastern border

Restrictions to contain African swine fever are disrupting wildlife movements along Finland’s southeastern border, but they are not expected to cause lasting harm to wild animals unless they remain in place for years, Yle reports.

Riku Lumiaro, a biodiversity specialist at the Finnish Environment Institute, said the duration of the restrictions would determine their effects. A year or two would make little difference, he said, but restrictions lasting several years could reduce genetic diversity, particularly among wolves.

Hunting is banned in the disease’s core area, and wildlife gates in the eastern border fence have been closed to prevent wild boar from leaving the infected zone and spreading the disease. The gates had become part of animals’ usual routes, and their closure has disrupted movement, according to Finland’s Southeast Finland Border Guard District.

Large mammals including bears, wolves, moose, wolverines, wild boar and forest reindeer have moved across the border. Bears and wolves can travel nearly 50 kilometres a day. The fence is not continuous, with waterways left open; Lumiaro said wolves, moose and bears are strong swimmers, while other animals can cross once the waters freeze.

The Finnish Food Authority suspects the disease is spreading north along the border, from southeastern Finland towards Lappeenranta, after cases were found outside the core area. It plans to expand the core area this week. The authority’s Sirpa Kiviruusu said wild boar have been searching along the border for new routes after their usual crossings were closed. Some bears have also traditionally gone to Russia to hibernate, while the start of the mating season can prompt male wild boar to seek new groups.

The authority plans to fence the core area, with work due to start towards the end of the year and finish early next year. The fence will include openings, including at roads, and is intended to slow and redirect wild boar rather than stop wildlife completely. Deer will be able to jump over it. Researcher Elmo Miettinen of the Natural Resources Institute Finland said wild boar can jump almost two metres and can also dig or push through barriers with considerable force.

Hunting is also prohibited in the core area. A regional game management official has warned that the restrictions could affect moose numbers and increase the risk of collisions with moose. A researcher said moose could benefit from a hunting-free autumn.