The impact of extreme weather in December to February 2014 on meta-population processes in European shags

许多气候模型预测极端天气事件的频率会增加。因此，了解极端天气对野生种群的影响是种群、进化和保护生态学的一个重要目标。短期影响包括高死亡率、身体状况恶化和爆发性运动，可能导致长期影响，如繁殖不良、群体缺失和扩散或迁移增加。在元种群规模上，一个地方的天气引起的死亡可能会对其他地方造成下游影响，特别是在部分迁徙的系统中，一些个体在冬季离开繁殖地，而另一些则留在那里。天气引起的死亡率和相关运动的空间异质性，然后可以大大重塑元人口的范围和结构。这种人口机制和动态是特别具有挑战性的理解，在长寿，迁徙物种与长期的繁殖前的生活史阶段，很难观察，冬季的影响和随后的繁殖的位置是分开的。然而，这些物种可能特别容易受到极端天气的影响，因为它们由于成熟延迟和繁殖率缓慢而从高死亡率事件中恢复缓慢。了解极端天气对长寿的移动的物种的影响至关重要，因为许多物种都是高度保护问题。为了满足决策者的需要，必须了解这些影响，并将其纳入用于为目前正在进行的政策决定提供信息的人口模型。英国最近的严冬天气创造了一个紧迫和宝贵的机会，以量化这一严重扰动的人口影响，使用部分迁移的欧洲shags Phalacrocorax aristotelis的元人口，这已经是一个长期的重点，由申请人领导的全年人口研究。沙格是长寿的，部分迁徙的沿海海鸟，在极端的冬季天气中死亡率很高。在过去的20年里，英国东北部的元人口下降了50%，我们收到了许多关于最近风暴后典型冬季地点的死亡和缺席的报告，这意味着元人口无疑发生了严重的扰动。由于我们最近的工作，我们拥有关于元种群人口统计（繁殖成功，生存，扩散，迁移）和分布的全面数据，无论是在最近的恶劣天气之前，还是在迄今为止的风暴中。因此，我们有一个独特的和非常强大的基线数据集。现在迫切需要的是在2014年繁殖季节和繁殖后迁移期间有针对性地收集数据，以量化跨季节人口对扰动的反应在多大程度上受到生存、繁殖成功、扩散或迁移方面的空间异质性的驱动。我们将回答三个具体的问题：a）天气引起的死亡率的空间格局如何影响集合种群结构？B）对存活个体繁殖成功的下游影响是什么？（c）对扩散和迁移的下游影响是什么？由于shags受到欧盟法律的保护，并可能受到海洋可再生能源开发的风险，因此还迫切需要提供最新证据，为目前正在进行的政策决策提供信息。元人口的规模、分布和人口结构无疑已经发生了重大改变，这意味着现有的知识和人口模型已经过时。因此，我们的第四个项目目标是立即进行数据分析，并提供为有效的海洋空间规划提供信息所迫切需要的最新人口模型。

Many climate models predict increased frequency of extreme weather events. Understanding the impacts of extreme weather on wild populations is therefore a critical aim in population, evolutionary and conservation ecology. Short-term impacts include high mortality, lost body condition and eruptive movements, potentially leading to longer-term effects such as poor breeding, missing cohorts and increased dispersal or migration. At the meta-population scale, weather-induced mortality in one location may cause downstream impacts elsewhere, especially in partially migratory systems where some individuals winter away from their breeding location while others remain resident. Spatial heterogeneity in weather-induced mortality and associated movements could then substantially reshape meta-population range and structure. Such demographic mechanisms and dynamics are particularly challenging to understand in long-lived, migratory species with protracted pre-breeding life-history stages that are hard to observe, and where locations of winter impacts and subsequent reproduction are separated. Yet such species may be particularly vulnerable to extreme weather since they recover slowly from high mortality events due to delayed maturity and slow reproductive rates. Understanding the impacts of extreme weather on long-lived mobile species is critically important since many are of high conservation concern. To fulfil the needs of policy makers, it is imperative that such impacts are understood and incorporated into population models used to inform currently ongoing policy decisions. The UK's recent severe winter weather has created an urgent and valuable opportunity to quantify the demographic effects of this severe perturbation, using a partially migratory meta-population of European shags Phalacrocorax aristotelis that is already the focus of a long-term, year-round demographic study led by the applicants. Shags are long-lived, partially migratory coastal seabirds that experience high mortality during extreme winter weather. The north-east UK meta-population has declined by 50% during the last 20 years, and we have received numerous reports of dead shags and absences from typical winter locations following recent storms, meaning that a severe perturbation to the meta-population has doubtless occurred. Due to our recent work, we possess comprehensive data on meta-population demography (breeding success, survival, dispersal, migration) and distribution both before the recent severe weather and also throughout the storms to date. We therefore have a unique and extremely powerful baseline dataset. What is now urgently required is targeted data collection during the 2014 breeding season and post-breeding migration to quantify the degree to which cross-season demographic responses to perturbation are driven by spatial heterogeneity in survival, breeding success, dispersal or migration. We will answer three specific questions a) How did the spatial pattern of weather-induced mortality affect meta-population structure?; b) What are the downstream effects on breeding success of surviving individuals?; c) What are the downstream effects on dispersal and migration? Since shags are protected under EU law and potentially at risk from marine renewables developments, there is also a specific urgent need to provide updated evidence to inform currently ongoing policy decisions. Meta-population size, distribution and demography have doubtless been majorly reshaped, meaning that existing knowledge and population models are obsolete. Our fourth project objective is therefore to undertake immediate data analysis and provide the updated population models that are imminently required to inform effective marine spatial planning.