Sorry benacre, not sure about your question. Do you mean you want to release the hedgehogs on to the allotments. If yes, then I think slug pellets can be harmful to hedgehogs, but, where are the hedgehogs coming from and what is the risk there. There is no such thing as a risk free life and the hedgehogs might be better off on the allotments than wherever they are now.. Maybe the people who use slug pellets could be persuaded to enclose them in jars hedgehogs can't get into or something like that.( Like small jars hlaf submerged in the ground with a few pellets in. Slugs attracted just the same but birds, hedgehogs etc can't get at. And chemicals not washed in among veg etc.)

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