A mink trapping project in Perthshire and Angus is helping wildlife return to rivers, according to those behind the cull.
Monitoring and trapping rafts have been set up in waterways from south Perthshire to north Angus.
Mink, which are native to America, eat creatures like water voles and ground nesting birds.
Since the project in began in April, 48 have been caught, with volunteers claiming that birdlife on waterways is now flourishing as a result.
The Scottish Wildlife Trust and Cairngorms National Park Authority are among a number of organisations behind the £920,000 Scottish Mink Initiative.
Michael Hardy, mink trapping volunteer, said: "Definitely seen a difference, there's more water hens now, I have not seen a water vole, the ducks are making quite a racket and they seem to be happy as well, more dippers as well.
"As the dippers tend to nest in the river bankings and the kingfishers, they have been devastated over the years as well."
Ann-Marie MacMaster, mink control officer, added: "Mink are really effective predators and they will go for water voles, ground-nesting birds, they'll take their eggs, chicks, the birds themselves, fish, eels and also rabbits as well.
"We're hoping it's going to make a huge difference to native wildlife, especially ground-nesting birds and water voles."