Woburn: Juvenile Cooper’s Hawk

August 22, 2016 in Nearby Landbirds

_W7I1047-001After pulling in to observe the Woburn Peregrines, had a nice show from three Cooper’s Hawk in an active series of aerial loops and active chase sequences.  The participants included two adult Cooper’s and a juvenile.  The juvenile Cooper’s has yellowish eyes and thin dark breast streaks.  At one point, the unbanded male peregrine falcon asserted his territorial defense with two chase efforts and then was satisfied with no further action!  The juvenile Cooper’s was a beauty to watch and photograph in fading late day low light!


Peregrine defending nest territory

March 3, 2014 in Near the Clock Tower

A fascinating moment while observing a Cooper’s Hawk on a rooftop proximate by about 75 meters to the peregrine falcon nest box located in the Clock Tower.  The Cooper’s Hawk was perched on the edge of the roof.  Without much verbal warning the peregrine strafed to Cooper’s at first and then went into a more direct attack mode next round.  Found this description from Cornell Birds of North American Online:  “Cade’s model, with nesting cliff as center, in general seems fairly accurate: series of threshold perimeters surround eyrie with decreasing defense as distance from eyrie increases. Inner perimeter may be only 200 m; within that, attacks always occur. In outer perimeter, attacks only occur over food or favored perches.”  Now that Cooper’s hawk has been put on notice!