Effects of a rabbit on nesting common terns

Reproductive biology of common terns (Sterna hirundo) was studied at an insular breakwater site at Port Colborne, Ontario in 1976 and 1977. The unusual occurrence of an eastern cottontail rabbit (Sylvilagus floridanus) in the ternery in 1977 disrupted nesting activity and nocturnal incubation attentiveness. Effects resulting from disruption of nocturnal incubation, including prolongation of incubation periods and retardation of evaporative water loss from eggs, are examined.