In the Kalahari Desert in South Africa live birds called the common social weaver (Philetairus socius).
They build massive nests, which from a distance look like a giant haystack incomprehensibly fallen on a pole. The base of these nests are usually trees or telephone poles. The birds make a frame out of large sticks and then build walls of dried grasses. They create separate “rooms” in the nest that are lined with softer grasses and fibers. Sharp spikes of straw protect the entrance tunnels from predators. These nests are the largest of all nests built by birds. They hold up to a hundred pairs of birds. Often, several generations of weavers live in such a huge nest at the same time.
The nests are well structured and provide the birds with a more favorable temperature compared to the environment. The central chambers retain heat better and are used for overnight stays. The outer chambers are used for sheltering in them during the day. In them the temperature is 7-8 degrees Celsius, while the air temperature ranges from 16-33 degrees Celsius.
Such a huge nest is divided into “rooms,” each containing a pair of birds: a male and a female. The largest colonies can exist for a hundred years or more.
Birds are called “social” not because they live in large colonies, but because they share their nests with several other bird species, including owls, vultures, eagles, red finches, and many others. The big birds warn the nest dwellers of danger. And the nest hosts also often learn from other birds where to find food.