Kingbird87
Not wishing to detract from you well reasoned and informative comments, but I would observe that the bird-strike was more likely to have occured over Bronx Park whilst on a heading of 360, having made the normal left after take off from 04 at LGA. It was here, when N106US reached it maximum height of 3,000 ft that the incident took place.
The 180 to align with the Hudson river then took place.