Enviro Perspectives on Association with Dave Rushworth


There are many instances of animals co-operating or associating with other species, presumably to increase their chances of survival. Many insects, birds and fish gather in dense swarms for the protection of individuals. Some mimic toxic or otherwise dangerous species for their own protection.

Predators co-operate with others to increase hunting success while others use the association of lights, roads, other human structures or disturbance. One example is the blue waxbill (Uraeginthus angolensis) that often builds its nest close to stinging wasps. The active colonies of wasps are efficient protection against primates and large avian predators but would probably be ineffective against snakes.

The blue waxbill is one of South Africa's small, colourful finches, with males darker than females, that is restricted to the drier eastern and northerly regions of the country. Although it is a seed-eater it will take insects when the opportunity arises. Its nest is a ball-like structure of fine grasses with a side entrance leading to a central chamber lined with feathers.

They normally lay three to four (but up to seven) small, white eggs. Their breeding cycle, like many small birds, is over within one month. The eggs take up to twelve days to hatch and the chicks fly within three weeks. Most small bird species will breed more that once during a prolonged rainy season, while the conditions are right.

What Came First?

As with the old question 'the chicken or the egg?', people often ask whether the birds build next to the wasps or the other way around. In this instance the birds always build next to the wasps. I have, on several occasions, watched the birds building next to an established wasp nest.

I have never observed or heard of anyone who has seen wasps building next to a blue waxbill nest. Wasps do build under the protective cover of large raptor and hammerkop nests but waxbills build and breed too fast for wasps to become established for any protective purpose.

The same type of question is posed concerning trees and termite mounds. With increased nutrients and moisture, the clay mounds are attractive to species of trees with a preference for these conditions. Observation will show whether the tree grew on the mound or whether the mound was constructed round the tree.

The answer in this case is that either the mound or the tree can come first. Most species of 'mound termite' do not eat living wood and the tree actually benefits from the surrounding mound in terms of support, nutrients and moisture.

Grasses Used in Nest Building

As with many other bird species, blue waxbills have quite specific requirements for nest-building materials. They choose fine, soft grass stems with heads that do not contain sharp or burr-like seed heads. This confines them to grass species of the genera Sporobolus, Panicum, a few Eragrostis and Briza. The last named grass is an introduced species, which is most popular.

If an area has been overgrazed or burned these waxbills will not be able to construct nests. They will be unable to breed or may have to move to other areas for this purpose. In some instances, where building material is in short supply, they will patch up suitable old nests of other species and breed quite successfully.

They are extremely resourceful little birds and add a lot of pleasure in return for a little bird seed in a protected part of the garden. Don't forget your birds (and other pets!) this holiday season and enjoy a wonderful Christmas as we celebrate God's manifestation on earth in the form of baby Jesus. May you have a peaceful, contented and blessed new year.

See Images of Bird Life in Kruger Park

Kruger National Park - South African Safari