The appearance of 'polecat ferrets' can bear great similarity to the native wild polecat from which they are probably descended. The two species are able to interbreed, which can also confuse matters. As the fur and facial colouring of polecat ferrets and true polecats can be almost identical, the main recordable differences are linked to certain skull measurements. If you ever wondered what the distinctive facial markings were for - it is thought to be a warning to predators that polecats taste nasty! In addition, their ability to produce a foul smell when threatened has earned them the name of 'foul marten'.

A very exciting development in recent years is that the wild polecat has been expanding its range eastwards from its stronghold in Wales and the Borders and now is just a county away from Suffolk!

Before considering what the arrival of the native wild polecat on our doorstep might mean, we ought to look back at the past. Polecats are thought to have become extinct in Suffolk sometime around 1900-1910. We know that in 1880 they were still present in the county, as throughout much of the British Isles, although probably in low numbers. Polecats were perceived as vermin and an early Act of Parliament encouraged their extermination by allowing churchwardens to pay a bounty on the corpses. The arrival of the (now illegal) gin trap in the mid-1800s also contributed to their scarcity, since polecats proved particularly vulnerable to this form of trapping.

Following a reduction in gamekeeping activity after the First World War, polecats began to recover some of their former range, moving out from their stronghold in Wales. In addition, methods of capturing or killing polecats have been restricted by more recent legislation, so that it is now illegal to trap a polecat without a licence. By the 1990s they had continued to spread eastwards, reaching counties such as Derbyshire and Oxfordshire. The latest reports show that they have been recorded in Cambridgeshire, Hertfordshire and Lincolnshire and are likely to be in Essex - so it can only be a short while before they reach Suffolk.

Polecats are mostly active at night and eat a wide variety of mammal prey, including rabbits, rats, voles and mice. They have also been reported to take poultry, wild birds and their eggs and amphibians. As they are thought to prefer valley and lowland habitats where their prey species will be most numerous, Suffolk's river valleys are likely to offer very good habitat for them.

Although the return of the polecat to Suffolk may be perceived as a mixed blessing, it is likely that the benefits will outweigh any negative aspects. Polecats are efficient controllers of agricultural and forestry pests and the latest research has shown that rats make up 65% of their diet.

So the next time you spot what looks like a wild ferret, it is worth bearing in mind it might be our truly native form back home at last and hopefully here to stay.

This is an extract from the Trust's magazine 'Suffolk Wildlife'.

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