Weaver news

Weaver species ranked by mean colony size

2013-06-21 (380)


phown 3739

PHOWN has been running for nearly 3 years, collecting data on nesting by weavers, and most records include a nest count. Here we look at how average colony size varies by species. Ploceus weavers with more than 10 nest count records were extracted. A summary of colony sizes per species is presented in the table below with the minimium, mean, and maximum nest counts, followed by the sample size.

Chestnut Weavers, Lesser Masked Weavers and Village Weavers have the largest colonies (average of >30 nests). Eastern Golden Weavers and Cape Weavers have medium sized colonies on average (about 20 nests per colony). The Southern Masked Weaver mostly has small single-male colonies of 5-6 nests, but occasionally colonies are larger with several males in the colony. The last 4 weaver species are usually found in pairs that have single nests although a few old nests may be present, giving a slightly higher nest count.

Interestingly, even very colonial species occasionally build single nests, and the maximum colony size can be large for any colonial species.

Species Min Mean Max Records
Chestnut Weaver Ploceus rubiginosus 1 88.7 350 37
Lesser Masked Weaver Ploceus intermedius 2 49.1 200 49
Village Weaver Ploceus cucullatus 1 37.1 500 748
Eastern Golden Weaver Ploceus subaureus 1 20.7 120 67
Cape Weaver Ploceus capensis 1 20.4 348 833
Southern Masked Weaver Ploceus velatus 1 5.7 91 1489
Baglafecht Weaver Ploceus baglafecht 1 4.7 18 19
Holub's Golden Weaver Ploceus xanthops 1 4 15 21
Spectacled Weaver Ploceus ocularis 1 1.4 5 113
Dark-backed Weaver Ploceus bicolor 1 1 1 39

Many more PHOWN records are needed, even for the above species, but also for all the other weaver species. Several common colonial species have few records with nest counts, or no PHOWN records, so look out for some weaver colonies near you!

Thanks to all the citizen scientists who have submitted PHOWN records already!