From 2007 to 2020, annual island-wide censuses of king penguin chicks were undertaken in the second week of August each year. This data was compared to environmental variables to understand what variables can be further explored to understand king penguin population changes. This data set contains chick count data, environmental parameters and R scripts used to investigate the current trajectory of the Macquarie Island king penguin population in relation to environmental variables. This data has been published in ICES Journal Of Marine Science (DOI to be provided).

This indicator is no longer maintained, and is considered OBSOLETE. INDICATOR DEFINITION The size of the breeding population of King Penguins at Heard Island. TYPE OF INDICATOR There are three types of indicators used in this report: 1. Describes the CONDITION of important elements of a system; 2. Show the extent of the major PRESSURES exerted on a system; 3. Determine RESPONSES to either condition or changes in the condition of a system. This indicator is one of: CONDITION RATIONALE FOR INDICATOR SELECTION The breeding population of King Penguins is related to resource availability (nesting space and food), behavioural mechanisms (immigration/emigration and breeding effort/success) in addition to climate change and human impacts such as fisheries. Monitoring breeding population and interpretation of the data provides information on changes in the Subantarctic ecosystem. DESIGN AND STRATEGY FOR INDICATOR MONITORING PROGRAM Spatial scale: Heard Island (lat 53 deg 06' 00.0" S, long 73 deg 31' 59.9" E). Frequency: 2-3 years. Access to remote colonies and other logistical constraints do not permit annual visits. Measurement technique: Each colony is visited and individual birds are counted from the ground by two or three personnel performing replicate counts. Further counts are obtained by oblique ground and aerial photography. All breeding individuals in a colony are counted. Considerations regarding disturbance associated with census visits are also incorporated into monitoring strategies. The lack of annual census data does not reduce the value of these long-term monitoring programmes. RESEARCH ISSUES The king penguin breeding population at Heard Island has increased at almost 20% per year since the late 1940s; other king penguin populations throughout the Southern Ocean have also increased, but not as rapidly. At present, there is no alternative hypothesis to that previously proposed, that these population increases are sustained by the enhanced availability of myctophids, the principal prey of king penguins (Woehler et al. 2001). LINKS TO OTHER INDICATORS