Methodology:

Counts of the number of breeding pairs, chicks and chicks in crèche are undertaken following the CEMP Standard Methods for monitoring of predator species (CCAMLR 2014). Breeding chronology (Method A9) is established for the whole island using the 'Mast' sub-colony. Sub-colony counts are carried out daily during the arrival period and the date of the first egg laid is recorded. Following this 100 marked nests are closely monitored and from this dates for island-wide counts are established. The breeding population count (method A3A) takes place one week after 95% of nests contained eggs. Counts of chicks are made twice: the number of chicks per breeding pair are recorded after hatching ends, and later the number of chicks forming crèches are counted prior to fledging (Method A6C). Further details of the survey methods can be found here: CEMP Standard Methods, https://www.ccamlr.org/en/document/science/cemp-standard-methods, CCAMLR, Hobart Australia.

The sub-colonies have been categorised into those that are in areas visited by tourists (six colonies are 'visited areas') and those which are not (four colonies are 'control areas'). Locations of the colonies surveyed on Goudier Island can be seen in the map file.

Data quality:

All raw data appear as collected and have not been cleaned via post-processing analyses.