When is a falcon most likely to "throw up"?

A falcon is most likely to "throw up" or regurgitate after a stoop—especially if the quarry dodges—because this situation creates stress on the bird. During a stoop, a falcon dives towards its prey at high speed. If the prey successfully evades capture, the falcon's physical and physiological response can include the expulsion of undigested food or pellets. This is partly due to the bird's need to quickly alleviate any unwanted weight that could affect its agility and speed during subsequent attempts at hunting.

The other situations listed may not trigger this response as consistently. After a successful meal, a falcon typically digests its food without issue. While perched for a long time, the bird is usually just resting and does not actively engage in hunting or exertion that would lead to regurgitation. Similarly, when being fed directly by a falconer, the bird is receiving food in a controlled manner, reducing the likelihood of stress-related regurgitation. Thus, the context of the falcon's actions during a hunt and the physical pressures involved make the response after a stoop the most relevant scenario for this behavior.