Do Post-Hatching Factors Limit Clutch Size in the Cape BArren Goose, Cereopsis novaehollandiae Latham?

Abstract

The vigilance behaviour of geese was measured by the amount of time per day they spent with their heads raised, and also by the frequency with which they interrupted feeding to look up. Goslings were vulnerable to predation in the first 4 weeks after hatching. The adults' vigilance behaviour was higher during the 4 weeks after hatching than later, and this reduced the amount of time they spent feeding. It is argued that brood size and the adults' ability to protect the young are inversely related, and that larger broods, for this reason, raise the cost of reproduction. These factors are considered as posthatching limitations on clutch size.