An advanced detachment of orc troops had been invading the ruins, and were absentmindedly feeding on honey buzzard eggs and chicks. This resulted in a marked decline of Hydeland's honey buzzard population.
These large avians typically build their nests in caves and ruins. They eat insects, reptiles, other birds, eggs, small mammals, etc. Their favorite foods appear to be wasps, and they will actively attack wasp nests in order to get at them. This leads to their nicknames of "Wasp-Eaters" or "Bug Buzzards".
With the orcs driven off, the wasp population will likely be reined in once again.