How is a Peregrine Falcon best described?

The best description of a Peregrine Falcon is its classification regarding being "difficult to man." This indicates that Peregrine Falcons possess strong instincts and behaviors that can make them challenging for falconers to train and handle. They are known for their high energy, strong hunting drive, and independence, which can complicate the training process.

In the context of falconry, managing a bird’s innate behaviors requires skill and understanding, as these birds may resist attempts to be tamed or trained due to their powerful natural instincts. This aspect of their behavior significantly impacts how falconers approach training and handling, necessitating a knowledgeable and patient approach.

While the other choices touch upon different aspects of birds and their characteristics, they do not accurately encapsulate the key traits that define the Peregrine Falcon. For instance, it is not smaller than a Merlin, as it is a larger species, nor is it predominantly delicate or sensitive to cold. Additionally, while some Peregrine Falcons can be migratory, they are not exclusively coastal falcons, as they inhabit various ecosystems. These reasons highlight why "difficult to man" stands out as the most suitable description.