Rare raccoon dogs removed from key bird habitat in Raisio using thermal drone

Six raccoon dogs have been captured and removed from the Raisio Bay birdwatching area in southwestern Finland after conservationists discovered the invasive species damaging nests, local public broadcaster Yle reports.

Birdwatchers raised the alarm after finding signs of raccoon dogs and mink at a ringing station in the reeds, where declining chick survival rates had been observed. The animals were located and removed just before the nesting season began, using a thermal camera-equipped drone to pinpoint their hiding spots in the dense vegetation.

“Without intervention, their numbers would have multiplied”
Markus Ahola, a local birdwatcher, told Yle that raccoon dogs—classified as harmful invasive species in Finland—destroy bird nests, particularly targeting eggs, while mink prey on chicks and adult birds. “We noticed birds torn apart by raccoon dogs or mink. Sometimes you can spot them with binoculars, but the drone’s thermal camera was essential for precise location,” he said.

The operation, carried out in April, involved tracking dogs and hunters working with the Helmi invasive predator control project. The drone guided the team to the raccoon dogs’ exact locations in the reeds near Raisio’s town center, where the animals were then captured. “The dogs flushed them out, and the hunter removed them,” Ahola explained.

Long-term monitoring needed to assess recovery
While six raccoon dogs have been removed, Ahola noted that effects on bird populations won’t be immediately visible. The site contributes data to Finland’s national bird monitoring program, with hopes that reductions in nest predation will become evident over the coming years. “Young raccoon dogs disperse to find new territories, so control efforts must continue to keep the area clear,” he added.

Mikko Toivola, project manager for Helmi, emphasized the scale of the problem: had all four breeding pairs in Raisio Bay reproduced successfully, the area could have hosted 35 raccoon dogs by autumn. Cities like Raisio provide ideal habitats, with parks and food sources supporting nocturnal foraging, while the reeds serve as daytime shelters. “They’re unfazed by humans—people walk just meters away, and the animals don’t react,” Toivola said.

Drones prove critical for urban predator control
Thermal drones, permitted for invasive species management since 2025, have revolutionized detection. Toivola observed that raccoon dogs ignore drones entirely—unlike lynxes or foxes, which react noticeably—making them highly effective tools. “This method is perfect for urban wetlands. Cities have dogs that can be trained for tracking, and staff can learn to identify invasive predators,” he said.

The Raisio operation required collaboration between birdwatchers, who secured emergency permits from the Finnish Safety and Chemicals Agency (Tukes), and the city, which provided funding. Toivola called it a model for similar efforts: “Many cities have reedbeds where this approach could work.”