The Sociable Weaver (Philetairus socius) is a small brown songbird that lives in southern Africa. Despite its unassuming appearance, this species displays some truly astounding behaviors that set it apart from other birds.
If you have never heard of these cool birds, now is your chance to find out about their fascinating habits and behaviors.
Identifying the Sociable Weaver
The Sociable Weaver is a small brown weaver with a thick, conical, and blueish-gray bill. The pattern on its back and flanks is scaled, and they have an identifiable dark bib.
In the wild, they live exclusively in South Africa, Namibia, and Botswana, with the greatest concentration of their numbers in South Africa.
They are also found in three zoos worldwide: the San Diego Zoo, the Zoologischer Garten Basel in Basel, Switzerland, and the Zoo Frankfurt am Main in Frankfurt, Germany.
The Sociable Weaver’s Unique Nest Construction
The sociable weaver is best known for building enormous communal nests that house entire colonies of these birds. These massive nests can be over 20 feet wide and 10 feet tall, with over 100 separate nesting chambers inside.
Think of them like giant haystacks perched in trees throughout the arid Kalahari Desert.
Constructing these mammoth nests requires cooperation from the whole colony — a big part of why they are called “sociable.”
More facts about the Sociable Weaver’s nest:
- The outer shell is made from large twigs and gives the structure its overall shape
- Sharper sticks are incorporated to deter snakes and other predators
- The inner chambers where the birds roost and breed are lined with soft plant materials and fur to provide insulation and warmth
- Males are responsible for carrying most of the large supporting twigs for the outer shell, while females gather the bulk of the smaller materials for the inner chambers
- Sociable Weavers also deliberately push green grass into the walls, which then dry and strengthen the nest
The materials for the nest need to be replenished frequently, so these birds are constantly working together to maintain the nest. On freezing nights in the desert, this nest keeps the birds warm and insulated. In contrast, on scorching hot days, the outer rooms of the nest provide plenty of airflow that keeps the birds cool.
Sociable Weavers are non-migratory who use the same nests for years. Some have used the same nests for over a hundred years.
A Home for Many Species
Remarkably, the sociable weaver nests house more than just the weaver colonies. A variety of other animal species rely on the structures for shelter.
This includes:
- Pied barbet
- Familiar chat
- Ashy tit
- Red-headed finch
- Rosy-faced lovebird
In addition to birds living within the nesting structure, you may also find vultures, eagles, and owls perching on the roof.
It’s not just birds, either! Sometimes snakes and lizards will take up residence in the Sociable Weaver nest — which probably leads to snakes consuming weavers and other birds in the nest, too.
Why are Sociable Weavers okay with this cohabitation? Well, it seems like this is likely an instance of symbiosis, in which multiple species benefit one another. Having more individuals in the nest may make the colony safer from predators. Additionally, the weavers can watch the other animals to find more food sources.
When under attack, Sociable Weavers may join together to noisily dive-bomb the predator — especially if the predator is heading toward the chicks.
The Sociable Weaver’s Diet
Sociable Weavers are primarily insectivores whose diet mostly consists of termites. They will also eat seeds, but they prefer insects.
They have cone-shaped beaks that they can use to probe for bugs that live in the grasses and Acacia trees.
Sociable Weavers rarely need to drink water; all of their hydration comes from the water in the insects that they eat. This is why they are so good at surviving in the arid desert conditions of South Africa, Namibia, and Botswana.
About That Name: The Sociable Weaver’s Complex Social Life
As their name indicates, sociable weavers are highly social birds. Their nests can hold 5-100 nesting chambers, which means that there may be up to 400 or 500 individual Sociable Weavers in a single nest!
These birds are very collaborative, and they don’t just work with the other birds in their colony. They are also constantly preparing the nest for future generations; this inter-generational cooperation is very cool to observe!
Speaking of collaboration, juvenile Sociable Weavers don’t immediately branch out on their own and start breeding and raising young. Rather, they stay in the nest and help to raise the other babies, even if they’re not related to them.
“While most songbird species breed before they even turn a year old, sociable weavers rarely breed before the age of two. Instead, these younger birds help raise other nestlings–their siblings as well as unrelated chicks–by gathering food and maintaining the nest’s fluffy interior chambers and external sticks and grass.”
Nest sharing like this may help them avoid some of the drawbacks of living in a harsh desert environment. Working together allows the birds in these colonies to overcome limitations in the amount of available food and shelter.
For Sociable Weavers, cooperation is key to their survival!
Successful Survivors
The sociable weaver’s unique adaptations allow it to thrive in the dry African savannas. This is reflected in its conservation status. The population is described as stable and the species is classified as Least Concern by the IUCN.
One sign of their adaptability is their use of telephone/utility poles. As human activity expands, the Sociable Weaver adapts. They are good at living alongside people, and they will use these poles as the strong base of their nest structure.
Their biggest predators are snakes, with high rates of nest predation.
Thanks to its remarkable social bonds, shelter-building skills, and ability to thrive on scarce resources, the sociable weaver seems poised to continue its reign as a denizen of deserts long into the future. Their impressive nests will likely decorate the South African desert for generations to come!