What does the term "cast" refer to in falconry?

In falconry, the term "cast" specifically refers to the act of disgorging a pellet. This process involves the raptor expelling indigestible parts of its prey, such as bones, fur, and feathers, after it has digested the edible portions. This behavior is natural for birds of prey and serves as a means for them to rid their bodies of material that they cannot digest. Disgorging pellets is an important aspect of maintaining a hawk's health, as it helps indicate how well the bird is processing its food.

While the other options cover different aspects of falconry, they do not define the term "cast." For instance, the act of catching a bird pertains more to the hunting strategies used in falconry rather than the biological processes of the raptor. Flying two falcons together could refer to a specific training technique or a hunting strategy, but it does not describe the term in question. Additionally, the way to train a hawk encompasses a broad range of methods and techniques that would not specifically relate to the term "cast." Therefore, recognizing that "cast" pertains to the disgorging of pellets is essential for understanding the natural behaviors of birds of prey in falconry.