May 2018 - Regular raptor surveys in April revealed something very unusual indeed: a red-shouldered hawk (Buteo lineatus) nestling in a great horned owl (Bubo virginianus) nest! Park biologists watched the resident great horned owl nestling and its new foster sibling preen each other, check out their surroundings, doze together, and otherwise behave very much like normal nestmates. The adult great horned owl that initially flushed from the site also finally returned and settled to sit with both nestlings.
Park raptor biologist Gavin Emmons speculates that the great horned owl adults originally snatched the young hawk from its nest and brought it back as food for their own nestling. For some reason, they then decided to adopt and raise the hawk rather than eat it, a behavior that has only infrequently been seen with certain eagle species adopting rather than eating hawk, osprey, or kestrel nestlings. However, park staff had never heard of this rare event happening between owls and daytime raptors.