Peregrine Falcons

Hi, My name is Alexander, I am acting manager at the Scottish Seabird Centre in North Berwick, Scotland. We are lucky to have two pairs of peregrine falcon here in the Firth of Forth and I have been watching them and monitoring their behaviour for more than a year. However today I saw something I have never seen before and hopefully someone within this community may have the answer. I watched a male peregrine bring down a prey, I believe to be a guillemot, but instead of feeding he took the carcass underneath an area of tree mallow and left it and flew off. This was at 10:20 AM and he has not been back to the carcass since. I did not know that peregrines 'cache' food. Is this behaviour common or can anyone explain what this is? Many thanks. Alex