Kagu or scratch away debris. Kagus are monogamous breeders, generally forming long-term pair bonds that are maintained for many years, even possibly life. Kagu can be long lived, with birds in captivity living for over 20 years. A single nesting attempt is made each year, although should the first nesting attempt fail a second attempt is made that year. A simple nest is constructed, which is little more than a heaped pile of leaves, although in some cases the egg may be laid directly on the ground. The nest is not concealed but is usually adjacent to a tree trunk, log
Kagu gruiform, the kagu is generally considered related to the extinct adzebills from New Zealand and the sunbittern from Central and South America. Recent studies do indicate that the sunbittern is the closest living relative of the kagu. For example, Fain & Houde found these to be certainly sister taxa. They and the mesites did not group with traditional Gruiformes in their study, but instead with their proposed clade Metaves, which also includes the hoatzin, pigeons, Caprimulgiformes, flamingos, tropicbirds, Apodiformes, sandgrouse and grebes. The internal structure of this group was not well resolvable by their data, although later studies confirmed a