Demographics of an Adelie penguin population at Bechervaise Island, Mawson, Antarctica

This indicator is no longer maintained, and is considered OBSOLETE.INDICATOR DEFINITIONDemographic parameters for the Adelie penguin at Bechervaise Island near Mawson.TYPE OF INDICATORThere are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: CONDITIONRATIONALE FOR INDICATOR SELECTIONThe 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 mortality. Population reconstruction techniques provide estimates of recruitment and mortality and relate these functions to population size and/or population trends. These studies may alert us to possible changes in the ecosystem particularly related to the availability of food to the penguins or changes to the physical environment. The identification of the cause of changes must come from detailed investigations of food availability and the environment carried out at the same time.Annual breeding success at Bechervaise Island (eggs laid to chicks fledged) varies enormously from 0 in catastrophic years to above 1 for good seasons. The population at Bechervaise Island near Mawson has been monitored since 1990 as part of the CCAMLR Ecosystem Monitoring Program. Chicks and adults have been tagged annually. The number of breeding pairs has increased slightly between 1990-2001, but changes in the non -breeding population are unknown. Demographic studies based on the return rate of birds tagged as chicks provide information on trends in the overall population and the net rate of recruitment. Since it is intended that this program be undertaken indefinitely it makes this population an excellent subject for monitoring in the context of the SOE.DESIGN AND STRATEGY FOR INDICATOR MONITORING PROGRAMSpatial Scale: Restricted to the Mawson region. Similar studies are carried out by other national research programs at Terra Nova Bay (Italy) and on the Antarctic Peninsula (USA).Frequency: AnnualMeasurement Technique: The Adelie penguin population at Bechervaise Island consists of approximately 1800 breeding pairs. Each breeding season since 1990/91 in excess of 250 chicks have been given implanted electronic identification tags. The return of birds to their natal colony has been detected automatically by the Automated Penguin Monitoring System (APMS)or by checking all birds with a hand held tag reader. Additional and associated biological data as prescribed by CCAMLR (1997 are collected to aid interpretation of demographic and other trends. To detect trends in the population size and in demographic parameters, particularly of recruitment, it will be necessary to maintain an annual tagging program of chicks and recording of all tagged birds.RESEARCH ISSUEScomprehensive analysis of the data collected over the duration of this study is required to determine natural variation and potential anthropogenic influences affecting Adelie penguin population dynamics.LINKS TO OTHER INDICATORSSea-ice extent and concentration.

本指标已停止维护，视为废弃指标。

### 指标定义
莫森站附近贝彻韦斯岛（Bechervaise Island）的阿德利企鹅（Adelie penguin）种群人口统计学参数。

### 指标类型
本报告共使用三类指标：
1. 描述系统重要组成要素的状态；
2. 展示作用于系统的主要压力程度；
3. 确定对系统状态或状态变化的响应。
本指标属于**状态类**指标。

### 指标选取依据
阿德利企鹅是寿命较长的海鸟，依赖磷虾为食。预计海鸟的食物（磷虾）可获得性发生重大变化时，最终会反映在繁殖种群的补充量上。磷虾可获得性的变化，直接与人为或自然因素引发的生物、物理环境变化相关。老龄化种群可能在繁殖群落的数量上呈现出表面的稳定性，但这种状况可能掩盖了补充量的下降。若要判断种群是否受到环境影响，需开展详细的人口统计学研究。
针对已知年龄组的动物种群开展多年的人口统计学研究，可用于确定导致补充量和/或死亡率出现观测变化的因素。种群重建技术可估算补充量与死亡率，并将这些函数与种群规模和/或种群趋势相关联。此类研究可帮助我们察觉生态系统的潜在变化，尤其是与企鹅食物可获得性或物理环境变化相关的变化。确定变化的成因，需同时开展食物可获得性与环境的详细调查。
贝彻韦斯岛的年度繁殖成功率（从产卵到雏鸟离巢）差异极大，灾年为0，佳季则高于1。1990年起，作为南极海洋生物资源养护委员会（Commission for the Conservation of Antarctic Marine Living Resources, CCAMLR）生态监测计划的一部分，莫森站附近的贝彻韦斯岛种群得到持续监测，每年都会对雏鸟和成鸟进行标记。1990-2001年间，繁殖对数量略有增长，但非繁殖种群的变化情况尚不明确。基于雏鸟标记个体的回捕率开展的人口统计学研究，可提供关于整体种群趋势与净补充率的信息。由于该计划拟长期开展，因此该种群成为南极环境状况（State of Environment, SOE）监测框架下的绝佳研究对象。

### 指标监测计划的设计与策略
#### 空间尺度
限定于莫森地区。意大利在特拉诺瓦湾、美国在南极半岛开展的同类国家研究项目，也采用了类似的研究方案。
#### 监测频率
年度
#### 测量技术
贝彻韦斯岛的阿德利企鹅种群约有1800对繁殖对。自1990/91繁殖季起，每年都会为超过250只雏鸟植入电子识别标签。鸟类返回出生地繁殖群的情况，可通过自动化企鹅监测系统（Automated Penguin Monitoring System, APMS）自动检测，或使用手持标签阅读器对所有鸟类进行检查获取。同时收集CCAMLR（1997）规定的相关附加生物学数据，以辅助解释人口统计学与其他趋势。为检测种群规模与人口统计学参数（尤其是补充量）的趋势，需长期开展雏鸟年度标记计划，并记录所有标记个体的情况。

### 研究议题
需对本研究周期内收集的数据开展全面分析，以确定影响阿德利企鹅种群动态的自然变异与潜在人为影响因素。

### 与其他指标的关联
海冰范围与浓度。