New Ruvu Weaver colony discovered

A new colony of Ruvu Weaver – a highly localised species endemic to eastern Tanzania – has been found, sparking hope for the Near Threatened bird.

The colony was discovered in March 2023 by researchers from University McGill in Canada, as reported by Ornithomedia. They found 14 birds and four nests in the colony along the Ngerengere River during a visit to the wetlands near the Mindu Dam, not far from Morogoro.

A displaying male was seen, and the nests described, and sounds recordings of a singing male were obtained – thought to be the first time that vocalisations of Ruvu Weaver have been recorded.

Tanzanian endemic

The discovery of the new colony, although small, is important because the species is highly localised and therefore vulnerable. It is listed as Near Threatened by the IUCN. Dam and river development projects could threaten its habitat, and it is therefore essential to identify as many nesting sites as possible to protect them.

Ruvu Weaver is endemic to Tanzania, where it is only found in the east of the country, along the Wami, Ruvu and Rufiji river basins and on the shores of Lake Tagalala. Its biology and distribution are poorly known, however.

It breeds in wetlands, but ranges widely into surrounding savanna and woodland, and occurs alongside the very similar Eastern Golden Weaver, from which Ruvu Weaver was split as recently as 2021.