The pint-sized predator is not endangered but its habitat in Swiss meadows is increasingly coming under pressure as agricultural land is lost to construction, Pro Natura said on its website.
The stoat, whose brown coat changes to a pure white in winter, is a skilled mouse catcher.
It is appreciated by farmers as it specializes in catching voles, which cause damage to meadows by the mounds they create.
But in many areas stoats are becoming rarer because of a lack of places to hide, meaning that the predator is itself increasingly preyed upon, Pro Natura said.
Hedgerows, boulders and tree branches are all important for the animal’s survival.
The nature protection organization said it had chosen the member of the weasel family as its animal of the year to highlight the need for a varied agricultural landscape offering a diversity of natural habitats.
This would not only ensure the preservation of the stoat but also many other animal and plant species.
The stoat and weasel, which are both native to Switzerland, are related to martens.
Stoats grow to between 20 and 30 centimetres in length and are amongst the world’s smallest predators.