The owl remained in the area until May 2.  After the first day it moved its daytime roost from the bone pile into a nearby shed.  The owl spent the next three daytimes perched on a propane cylinder, but was gone each evening after dark.  A Leach's Storm-petrel colony was handy, and the owl may have been feeding on them - one morning the owl was standing with a dead petrel in its claws.  Petrels coming into the colony at night were perhaps easy prey for the nocturnal predator. 

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