Hello Fellow Fledges,
Below are direct quotes from Cornell Birds on Line regarding crows and predation. See bold print elements, relevant to recent discussions.
I observed a Barred owl family for two months this Summer and sometimes would locate them when 20-200 crows would aggressively harass the adults or young. The young owls were often visibly frightened, often showing startle responses to the crows. The crows gave wider berth to the adults. The adults showed no startle response, but the adult male made low, soft sounds when near the fledges and in the presence of the crow mobs.



Dan Reiff
MI

"Predation


Kinds Of Predators; Manner Of Predation


Predators of nestling and/or fledgling American Crows include raccoon, Great Horned Owl ( Chamberlain-Auger et al. 1990 , Caffrey 1992 , McGowan 2001a ), Red-tailed Hawk ( Buteo jamaicensis ; Tener 1954 ), Red-shouldered Hawk ( Caffrey 1992 ), Cooper?s Hawk ( Caffrey 2000b , McGowan 2001a ), and domestic cat ( Felis catus ; McGowan 2001a ). Adults fall prey to a variety of predators ( Gross 1946 ); e.g., Golden Eagle ( Connolly et al. 1976 ), Bald Eagle ( Haliaeetus leucocephalus ; Todd et al. 1982 ), Northern Goshawk ( Accipiter gentilis ; Meng 1959 ), Great Horned Owl ( Caffrey 2000b ), Red-tailed Hawk ( Baumgras 1945 ), Sharp-shinned Hawk ( A. velox ; S. E. White in Gross 1946 ), Merlin ( James and Oliphant 1988 ), and Barred Owl ( Cahn and Kemp 1930 , Bent 1938 ). For more references, see Black 1941 and Gross 1946 .
"Responses To Predators


Mobs throughout the year, but some species particularly during breeding season; e.g., Red-tailed Hawk and Common Raven ( Jollie 1976 ). Appears to distinguish hawks that are hunting, and thus potentially dangerous, from those merely flying from A to B ( Kilham 1989 ). Species mobbed include Sharp-shinned Hawk, Cooper?s Hawk, Black Vulture ( Coragyps atratus ), Turkey Vulture, Bald Eagle, Crested Caracara ( Caracara cheriway ), American Kestrel ( Falco sparverius ), Barred Owl, Great Horned Owl, Common Raven, Blue Jay ( Black 1941 , Kilham 1989 , Bockstie 1995 ). "