The fearsome Australian hornet. or is it? Actually these large yellow and black wasps are mason (or potter) wasps, though due to their large size and appearance they are called hornets. Abispa spp. collect soil and mud to build their nests which can often be found on the sides of buildings and thick vertical surfaces. Regurgitated water is combined with their collections to amass a conglomerate of mud spheres. One egg is laid in each brood cell after it is constructed, and the female will provision the future larvae by depositing a paralyzed caterpillar or spider inside the chamber. Because these wasps do not have large colonies they have a shy demeanor and readily flee when a threat gets too close to their nest. Initially I scared away the first wasp by accident, and after searching briefly I located the mud nest. I took the following pictures after sitting underneath the tree just a quarter of a meter under the nest, getting a great view of their nest-building behavior.
Photographed in situ