User blog comment:SayuriDarling/Full first chapter of The Mark of Athena/@comment-4606607-20120613003935/@comment-5112532-20120613163758

Maybe the owl is the presence of Athena, or someone/thing related to owls. I doubt that there would be a giant owl watching from the sky as Jason and Percy fight. It did say that it will be a scene from the book, so it might represent the two camps fighting but J and P will also fight, OR it could be a dream.