Learning from long time series of harvest and population data - Swedish insights for European goose management

Goose management in Europe is faced by multiple challenges, as some species are declining and in need of conservation actions, while other populations have become very abundant, resulting in calls for increased harvest.

Sweden has long-term series of harvest data and counts of breeding and autumn-staging geese. We used national data (indices) for greylag goose, bean goose, and Canada goose to study shifts in temporal trends and correlative patterns, and to infer possible causal links between harvest and population trends. Our study provides an opportunity to guide management given the data collected within the present monitoring, as well as to suggest improvements for future data collection.

The populations of greylag and Canada geese increased in Sweden 1979–2018, but this long-term trend included a recent decrease in the latter species. Bean goose breeding index decreased, whilst staging numbers and harvest varied with no clear long-term trend. For Canada goose, our analysis sug...

欧洲鹅类管理面临多重挑战：部分物种种群数量下降，亟需采取保护措施；而另有部分种群数量过度扩增，进而引发了增加狩猎配额的呼声。瑞典拥有长期的狩猎统计数据，以及繁殖种群与秋季停歇地鹅类的种群计数数据。本研究以灰雁（greylag goose）、豆雁（bean goose）和加拿大黑雁（Canada goose）的国家级监测数据（种群指数）为基础，分析其时间趋势变化与相关模式，并推演狩猎活动与种群趋势间可能存在的因果关联。本研究既依托当前监测所获取的数据为鹅类管理提供决策参考，也可为未来的数据采集工作提出优化方向。1979年至2018年间，瑞典境内灰雁与加拿大黑雁的种群数量均呈上升趋势，但后者的长期趋势中包含近期的种群下降。豆雁的繁殖种群指数呈下降态势，而其停歇种群数量与狩猎量则无明确的长期变化趋势。针对加拿大黑雁，本研究的分析结果表明……