Winter breeding season in the bird world

It’s breeding season in the bird world! While most bird species tend to lay eggs in the spring, some of our larger species (hornbills, vultures, cranes, etc.) are moving into their breeding season in the colder months. I’ll specifically be talking about nest building for our southern ground hornbills and lappet-faced vultures. For the Bird Team, preparing for breeding season can be very hands-off, like for the ground hornbills, or very involved, like with the lappet-faced vultures.

To get our southern ground hornbill pair (Zazu and Gumby) started, we open up their nest box and let them do their thing. Southern ground hornbills tend to nest in tree cavities in the wild, so staff built a box to suit the same purpose. Gumby will often be seen with a beak full of leaves that he’ll use to line the nest as they prepare for an egg. Gumby will do most of the preparation in the nest, but once an egg is laid, Zazu takes over. Zazu will incubate the egg in the nest box for approximately 40 days, while Gumby forages for food to give her. Like with the leaves, Gumby will carry as many food items in his beak as he possibly can, be it superworms or mice, to feed Zazu.

For our lappet-faced vulture pair, Anubis and Amana, we collect lots and lots of sticks for them. Inside their shed, they have a large platform that they can build their nest on, and they make a big nest. Lappet-faced vulture nests can get between four to seven feet across and one to two feet deep. Every day, the Bird Team will provide our pair with bundles of sticks of varying sizes that we collect throughout the Zoo, and occasionally from the surrounding park as well. Together, Amana and Anubis will carry the sticks they like to the platform, and will arrange them carefully so it’s very neat and difficult to take apart. Amana is noticeably better at getting sticks through the door than Anubis, but he’s enthusiastic about it! Once the nest is big enough, and nice and flat, they will start lining it with softer materials like leaves and grasses. When Amana lays an egg, she and Anubis will take turns incubating it for the full 54 to 56-day incubation period.

Both sets of birds have great nests in the making, and we can’t wait to see what they (and the rest of the winter breeders) create this year!

Claire S.
Keeper I, Birds