Please see this link for information on wildlife in NYC Parks.
If you see an injured animal, the best thing to do is leave the animal where it is, give it some distance, and call 311. The more information you can provide 311, the better. Please remember that young animals often look as if they have been abandoned, when in fact their parents are nearby. Abandoned domesticated animals (dogs, cats, chickens, rabbits, et cetera) should be brought to Animal Care & Control.