The effects of the number of nests within a neighboring space on reproductive success were examined in Egretta garzetta and Ardea cinerea in a heronry. Two neighboring spaces were defined: (i) the Neighborhood is a space enclosed by a sphere of radius DN whose center is located at a focal nest; (ii) the Surrounding is a space enclosed by a sphere of radius DS (DS > DN) that excludes the Neighborhood. DN and DS were set at several different values. The number of nests in the Neighborhood had a significant negative effect on reproductive success when DN = 0.5 m for E. garzetta and when DN = 1.5 m for A. cinerea . The number of nests within the Surrounding had a significant positive effect on the reproductive success of A. cinerea when DN = 1.5 m and DS = 3 m or DS = 4.5 m. These results suggest that to examine individual differences in reproductive success within colonies, we should choose the appropriate Neighborhood and Surrounding to detect the effects of interactions among neighboring individuals.
ASJC Scopus subject areas
- Ecology, Evolution, Behavior and Systematics