Loic Poidevin / Stoat (Mustela erminea) Creux du Van, Jura Suisse , Switzerland, September.

Erlend Haarberg / Stoat (Mustela erminea) in snow tunnel, Laponia UNESCO World Heritage Site, Swedish Lapland, Sweden. January. Third place in Golden Turtle Photography Awards 2017 competition.

Paul Hobson / Weasel (Mustela nivalis) head and neck looking out of yellow autumn acer leaves, Sheffield, England, UK.

Paul Hobson / Weasel (Mustela nivalis) investigating birch stump with bracket fungus in autumn woodland, Sheffield.

Paul Hobson / Weasel (Mustela nivalis) looking out of hole on woodland floor with snowdrops, Sheffield, England, UK.

Sven Zacek / American mink (Mustela vison) on ice with Common frog (Rana temporaria) prey, Tartumaa, Estonia, January. Introduced species.

Sven Zacek / American mink (Mustela vison) shaking off fur on ice with Common frog (Rana temporaria) prey, Tartumaa, Estonia, January. Introduced species.

Sven Zacek / American mink (Mustela vison) running on ice with Common frog (Rana temporaria) prey, Tartumaa, Estonia, January. Introduced species.

Espen Bergersen / Stoat (Mustela erminea) in winter coat, Andoy, Norway

Roland Seitre / Black-footed Ferret (Mustela nigripes) in burrow, North America

Erlend Haarberg / Stoat (Mustela erminea) digging in snow, in white winter coat. Vauldalen, Sor-Trondelag, Norway, May.

Erlend Haarberg / Stoat (Mustela erminea) in white winter coat running. Vauldalen, Sor-Trondelag, Norway, May.