Which avian predator is noted as the most persistent threat to unattended eggs and very young chicks in the colony?

Answer

Skuas

Skuas are identified as perhaps the most persistent aerial threat, specifically targeting unattended eggs and the weakest, youngest chicks.

Which avian predator is noted as the most persistent threat to unattended eggs and very young chicks in the colony?
Predatoranimalwildlifepenguinroyal penguin