What is a significant characteristic of field jesses?

Field jesses, commonly known as split jesses, are designed to serve specific purposes in falconry. Their name derives from the way they are constructed, allowing for flexibility in use while providing secure attachment to the bird's legs. This design enables falconers to easily manage the bird during training and handling.

The aspect of "providing excellent visibility" does not pertain to the jesses themselves, as they are primarily functional rather than visually impactful in terms of visibility. While jesses can be used with both trained and untrained hawks, they are not exclusive to trained birds, making that option less accurate in this context. Although field jesses can indeed be designed for easy removal, this is a common trait shared with many types of jesses rather than a unique characteristic of field jesses specifically. Therefore, the term "split jesses" accurately reflects both their construction and purpose in the context of falconry.