One of the most interesting things that has come out of our observations is the impact of Egyptian Geese on Black Sparrowhawks’ nests.
Egyptian Geese do not build their own nests. Normally they will lay their eggs in a scrape on the ground and line it with down from their chests. But they have long since realised that in such a nest their eggs are very vulnerable to predators. They have also realised that any platform, either in a tree or building, will offer more protection. As a result all the tree nesting raptors have to constantly fight off geese that are intent in taking over their nests.
Even if the geese do not actually manage to take over a hawks’ nest, during the confrontation between the birds, eggs and chick can die from cold. The geese also knock eggs and chicks out of the nest.
It is an unequal competition. The combined mass of the geese is about 4100 g versus the Black Sparrowhawks’ 1500 g.