The Bird That Turns Palms into Nests

By Bruce G. Marcot, Ecology Picture of the Week:

What is happening to this palm tree in central tropical Africa? It is being stripped of its fronds and slowly converted into a housing complex for Village Weavers.

Village Weavers, in this case, are not local artisans. Rather, they are a type of sparrow, found commonly in central and southern Africa, that weave hanging (pendant) nests.  They nest in colonies, sometimes numbering hundreds of nests, in human villages and can greatly alter the structure of the palm trees they inhabit.  

In this way, Village Weavers are ecosystem engineers and their key ecological functions include altering the structure of palms.

Why do they nest in colonies, when other weaver species of the region, such as Black-necked Weaver, are solitary? Colonial living might confer some protection for individuals from predators, or might ease the problem of finding potential mates. In their colonies, male Village Weavers display and try to attract females by fluttering their wings while hanging below their nests.  

Why build nests that seem precarious as they hang from the ends of stripped palm fronds? Again, the answer may lie in being safer from avian or tree-climbing predators, such as crows or snakes. In fact, the opening to Village Weaver nests is on the very bottom, making it even more difficult for predators to gain entry. 

  --Bruce G. Marcot

Image and text © Bruce G. Marcot, Ph.D. Research Wildlife Ecologist,
who produces the Ecology Picture of the Week website.