| Summary: | Progress Code: completed Statement: This indicator is now OBSOLETE. These data are no longer archived in this location, and are therefore not up-to-date. Chicks on Bechervaise Island have been given electronic identification tags annually since 1990/91. Detection of tagged birds has been undertaken annually at one colony on Bechervaise Island through the use of an Automated Penguin Monitoring System (APMS). Since the 00/01 season all birds breeding on Bechervaise Island and its near by Islands (Welch, Verner, Peterson and Klung Islands) have been checked for tags. These data are presently undergoing detailed analysis. This indicator is no longer maintained, and is considered OBSOLETE. INDICATOR DEFINITION Demographic parameters for the Adelie penguin at Bechervaise Island near Mawson. 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 Adelie penguin is a relatively long lived sea bird dependent on krill. It is expected that major changes in the availability of food (krill) to sea birds will be reflected ultimately in recruitment into the breeding population. Causes of changes in the availability of krill relate directly to changes in both the biological and physical environment brought about by man made or natural means. Ageing populations may give an outward appearance of stability in terms of numbers at a breeding colony but such a condition may mask a decline in recruitment. To determine whether there are environmental influences on the population it is necessary to undertake detailed demographic studies. Demographic studies carried out over many years on animal populations comprising known age cohorts are required to determine those factors responsible for any observed changes in recruitment and/or ...
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