Juvenile Cape Weavers have brown eyes, but after about 6 months young males start developing pale eyes while keeping the dull female like plumage. Males start developing the bright yellow adult male plumage in their second year, when they can start trying to attract females to nests they have built.
In their first year, however, immature males will start practising adult behaviours although they still have dull olive plumage. They start singing to practise their vocal skills. They visit breeding colonies to observe adult males building, and they start building their own nests. They may also practice leaf stripping. Often they will build near colonies with active breeding males, but sometimes the will build far from any colonies. These nests are untidy, and sometimes incomplete. But this helps them with skills in collecting nest materials, choosing nest sites, and actual nest building. Some of these activities are illustrated in short video clips below.
Immature Cape Weaver – 1. singing
An immature Cape Weaver singing at Die Oog in Cape Town, 25 July 2021 – note the bird is not in the adult male breeding plumage.
Immature Cape Weaver – 2. stripping reeds
Immature Cape Weaver – tearing off bits of dry reed near its partial nest (see below), Die Oog, 11 August 2021.
Immature Cape Weaver – 3. nest building
Immature Cape Weaver building a new nest (ring stage), Die Oog, 11 August 2021.