Cape weavers breed in noisy colonies in trees (often willows or Eucalyptus, rarely palms) and reedbeds.
They are polygynous, a male may have up to 7 female during season. Males breed singly or, more often, in colonies with 2-20 male. Males are highly territorial, chasing intruders from territory, threatening at borders by performing aggressive dance, singing and lunging.
When carrying nesting material to colony, male has nest arrival display, soaring up 2 m then gliding to nest site, calling on arrival. Once nest initiated, male displays at nest by ruffling feathers, shivering partly spread wings, swivelling body and singing.
If female enters territory, male displays either hanging below nest or perched alongside. If female enters nest, male responds with high-intensity wheezing song, either while hanging below nest or during circular display flight. Female apparently tests nest strength by pulling at material inside nest, then, once male leaves nest entrance, sits in nest chamber looking out of entrance; chases off male if he approaches at this stage. Female then leaves nest and may solicit copulation, adopting hunched posture with tail fanned, wings slightly spread and fluttered, giving reedy copulation call11. Male gives chattering call in response, flies and mounts female.