Nest box selection by floor laying and reproductively naive captive cockatiels ( Nymphicus hollandicus)

Abstract

These experiments examined the effects of offering captive cockatiels a choice of two types of nest boxes which differed primarily in type of nest entrance. The nest entrance to cavity-type boxes was circular and relatively small (6.4 cm diameter), while that to shelf-type boxes was rectangular and relatively large (15.2 cm × 26 cm). Cockatiels with histories of laying in cavity-type boxes tended to choose cavity-type boxes for their first and subsequent clutches. Cockatiels with histories of either laying on cage floors or not laying in the previous breeding trial were more likely to choose shelf-type boxes for first clutches but then switched to cavity-type boxes for subsequent clutches. Approximately one-third of reproductively naive cockatiels also chose shelf-type boxes for first clutches but increasingly used cavity-type boxes for subsequent clutches. Cockatiels laid in cavity-type boxes never switched to shelf-type boxes. Fertility, hatchability and fledging success (survival to 3 weeks of age) were all greater in cavity-type boxes, resulting in greater chick production. These results indicate that chronic floor laying can be corrected by offering cockatiels shelf-type boxes and that shelf-type boxes may be useful for improving captive reproductive performance of non-layers and naive layers as well.