Where did I go wrong

Today I was out and about and had the fortune of photographing a Kestrel at close range I was shooting at shutter priority and the kestrel was hovering at different angles to myself and I never had one good photo

Should I have Increased my shutter speed to accomadate the bird hovering ? or can you advise otherwise ? I must admit I have not had this problem before but was gutted when I downloaded the photos to see they were all rubbish.