What does the term 'passager' refer to in falconry?

The term 'passager' in falconry refers specifically to a bird that is capable of flying and is trapped before its first molt. This is significant because passagers typically exhibit a level of maturity and flight readiness that makes them valuable for falconers. They have developed sufficient muscle and flight capability, having spent time in the wild, allowing falconers to train them effectively for hunting tasks.

In contrast, other options describe different stages of a bird's life or characteristics that do not fit the definition of 'passager.' For example, a falconry bird taken as a nestling would be referred to differently, focusing on its young age and lack of flying experience, while a mature wild raptor describes an adult bird that is not typically categorized under the term 'passager.' A bird that has left the nest but has not yet taken flight suggests a fledgling stage that precedes the flying capabilities required to be considered a passager.