What is a primary reason not to fly a raptor during its moult?

The primary reason not to fly a raptor during its moult is related to the need to maintain the bird at a higher weight. During moult, a raptor is shedding old feathers and growing new ones, which is a physically demanding process. This requires the bird to conserve energy to ensure that it has enough resources to support feather regrowth and overall health. Keeping the raptor at a higher weight during this time helps to reduce stress and allows the bird to focus on moult without the added physical demands of flight.

Moulting can be a time of physical vulnerability, and excessive activity, such as flying, can not only impede the moult process but may also lead to injuries, particularly since flight could strain developing feathers that are not yet fully functioned. Therefore, maintaining appropriate weight and minimizing activity is essential for the well-being of the raptor during this stage.

The other options fail to address the critical factor of energy conservation and the specific needs that arise during the feather renewal process.