Nest searches are carried out on foot from our main field station since 1989 and from a secondary field camp inside the main goose colony since 1992. Nests are found during laying or incubation period by searches conducted over various areas in both sectors. At the main goose colony, systematic nest searches are conducted using two methods: (1) over an intensively-studied core area (ca 50 ha) located in the centre of the colony every year, and (2) since 1999, within a variable number of 1 and 2-ha plots randomly located throughout the colony. We also attempt to find the nests of as many neck-collared females as possible through intensive searches throughout the nesting colony. Nests are positioned with a GPS receiver and revisited twice or more to determine laying date, clutch size, hatching date and nesting success.
