When is it typically safe to leave a fledgling bird alone if it is found on the ground?

Leaving a fledgling bird alone is generally safe when it appears to be fully feathered and healthy. Fledgling birds are in a critical stage of development where they have left the nest and are learning to fly. At this point, they are usually well-feathered, indicating that they are capable of regulating their body temperature and have developed enough muscle strength to take flight soon. A healthy appearance, characterized by alertness and responsiveness, suggests that the bird is capable of foraging for food or waiting for its parents to return and provide care.

While other factors may influence the decision to intervene or not, such as whether the bird is calling for help or the time of day, a fully feathered and healthy fledgling is typically equipped to handle its situation. It is important to note that fledglings often spend time on the ground while their parents are nearby, continuing to care for them as they learn to fly and fend for themselves. Thus, ensuring the fledgling is healthy and feathered is the key indicator that it can be left alone without issue.