Important cautions

The birds welfare must always come first. NEVER disturb a site where a bird of prey may be nesting, or disturb roosting birds. All birds are protected by law, and there are special penalties for disturbing a barn owl close to its nest.
Pellets can sometimes be confused with droppings, especially of fox. Droppings are unpleasant to handle, so take care. If in doubt, leave well alone. Fox droppings are usually pointed at the end, the points having a twist in them.
When you go searching for pellets, always tell someone where you are going and when you expect to return.· Old buildings can be VERY DANGEROUS. You should always ask for a permission to enter them, and never visit them on your own. Never take unnecessary risks.
Pellets go mouldy very easily if they are kept in plastic bags or tubs. Store them in paper or cardboard containers.
Pellets are the ancestral home of clothes moths, so they are best stored out of doors. Keep your collection in a sealed container with tissue paper to absorb moisture if you bring them indoors.
It is a good idea to wear surgical gloves when handling and dissecting pellets.
Always wash your hands thoroughly after you have handled pellets.
Always throw away used cocktail sticks, or keep them for future use in a labelled container.