Does food supply affect egg size in Dunlin Calidris alpina schinzii?

Abstract

Food supply in relation to egg volume was studied in Dunlins Calidris alpina schinzii in the Getterön area, southwest Sweden 1995—1997. Food supply generally decreased from 1995 to 1996, and tended to increase from 1996 to 1997. Within a year, food supply generally increased over the breeding season. Mean egg volume followed the food supply pattern, i.e. egg volume decreased between 1995 and 1996, and increased between 1996 and 1997. However, within a year there was no change in egg volume over the season despite an increased food supply. The latter result may be a consequence of later breeding females investing less in their clutches, or that a seasonal increase in food supply compensated a lower potential for egg volume in late females (that may be of lower quality).