The medieval falconer was most likely to enseam his hawk when...?

The correct answer involves understanding the behavior and training regimen of hawks during the medieval period. A falconer would likely enseam a hawk when it was considered too fat, as enseaming is a method used to help a hawk lose weight. This process typically involves restricting food intake, which is essential for enhancing the hawk's energy levels and improving its readiness for hunting.

When a hawk is overweight, it may become lethargic and less effective in the field. Falconers aim to maintain their hawks in an optimal physical condition to ensure they are agile and responsive during flights. Therefore, the practice of enseaming is crucial for managing a hawk's weight and ensuring it is in peak condition for hunting and training.

Other scenarios, such as the hawk being hood-shy or sharp-set, typically refer to different aspects of training and readiness, but they do not relate directly to the need for weight management through enseaming. Similarly, enseaming immediately after capturing a hawk may not be standard practice, as newly captured birds require time to acclimate and may not yet need weight management. Thus, focusing on the hawk's condition being too fat provides the rationale for why enseaming would be employed at that time.