Desertion of the nest by adult raptors is most likely to occur:

Desertion of the nest by adult raptors is most likely to occur just prior to egg laying due to several reasons related to their nesting behavior and environmental factors. During this time, raptors are often assessing the suitability of their nesting site and may determine that the location is not ideal for raising young. Factors such as increased human disturbance, changes in food availability, or the presence of predators can lead to this decision.

As this period is critical for site selection, the birds are evaluating whether conditions are favorable for successful reproduction. If they sense that conditions are not suitable, they may abandon the nest before laying eggs rather than risk the failure of their breeding attempt. This proactive behavior helps ensure that they have the opportunity to breed successfully in the future rather than committing to a potentially unsuccessful nesting attempt.

In contrast, desertion during other stages, such as late incubation, hatching, or just prior to fledging, is less common as adult raptors usually remain committed to the survival of their young once they have invested time and energy into the nesting process.