Allotments can be a perennial problem where security is concerned, but at this time of year vandals and thieves will take advantage of the long, dark nights and lack of activity on the patch to break into poorly protected sheds and outbuildings no matter where they are.
Of course you can’t be on your allotment or in the garden 24/7 to watch over things, but modern technology can certainly help and if you prefer low-tech options, there are plenty of simple ways to make it hard for casual thieves to get at your goodies.