What was found
AT APPROX 0910(L), COMMENCED TAKEOFF ROLL. PIC/PF SET THRUST LEVERS TO APPROX 80 PERCENT AND COMMANDED SET POWER. PM/SIC CALLED 80 KTS, PF CONFIRMED 80 KTS. SHORTLY THEREAFTER, BOTH PILOTS SENSED YAW TO LT. PIC/PF ATTRIBUTED YAW TO CROSSWIND COMBINED WITH DISCONNECTION OF NLG STEERING. SIC/PM ATTRIBUTED YAW TO EFFORT TO AVOID APPROACHING BIRD. WHEN INCREASED RUDDER-PEDAL INPUT DID NOT PRODUCE DESIRED CORRECTION BACK TO RW CENTERLINE, PF/PIC GLANCED AT ENGINE GAUGES NOTING LT ENGINE N1 DECREASING THROUGH 91% DOWN TO 86%. PIC ABORTED TAKEOFF AT APPROX 100KTS. REDUCED BOTH THRUST LEVERS TO IDLE, APPLYING NORMAL BRAKING AND REVERSE THRUST. PM NOTIFIED TOWER OF ABORT REPORTING ENGINE ROLL-BACK.