Novel code for: Synchrony in adult survival is remarkably strong among common temperate songbirds across France

Synchronous variation in demographic parameters across species
destabilizes populations, metapopulations and metacommunities and
increases extinction risks. Revealing the processes that synchronize
population dynamics across species allows us to identify trans-specific
demographic processes that are subject to environmental forcing of
overarching importance. Using a Bayesian, hierarchical multi-site,
multi-species mark-recapture model, we investigated temporal interspecific
synchrony in annual adult local survival across 16 common songbird species
across France for the period 2001–2016. Adult annual survival was largely
synchronous among species (73% [47–94] of the variation among years was
common to all species), despite species differing in ecological niche and
life-histories. This result was robust to differences in migratory
strategy among species, uneven species sample sizes, and time de-trending.
Shared synchrony across migratory strategy suggests that environmental
forcing during the 4-month temperate breeding season has large-scale,
cross-specific, impacts among songbirds. At a scale ~1000 km, a likely
proximate mechanism of synchronization is forcing by weather-driven
variation in resources, which, in particular, determines the cost of
reproduction. However, the strong interspecific synchrony was not easily
explained by a set of a priori defined candidate weather variables, with
spring weather variables explaining only 1.4% [0.01–5.5] of synchrony,
while the contribution of large-scale winter weather indices may be
stronger, but uncertain (12% [0.3–37]). Future research may up-scale these
results to community dynamics, to understand compensatory intra- and
inter-specific demographic processes that preserve meta-communities from
synchronization.

物种种群统计参数的同步变异，会降低种群、集合种群（metapopulation）与集合群落（metacommunity）的稳定性，并提升灭绝风险。阐明驱动物种种群动态同步化的机制，有助于我们识别受关键环境因子调控的跨物种种群统计过程。本研究采用贝叶斯（Bayesian）分层多站点多物种种群标记重捕模型（mark-recapture model），针对2001–2016年法国境内16种常见鸣禽，分析了其年度成体局部存活率的种间时间同步性。尽管各物种种群的生态位与生活史存在差异，但物种间的年度成体存活率整体呈现显著同步性——年度间的变异中有73%[47–94]为所有物种共有。该研究结果在物种迁徙策略差异、物种样本量不均以及时间序列去趋势化的情况下均保持稳健。不同迁徙策略的物种均表现出同步性，这表明温带地区为期4个月的繁殖季内的环境驱动作用，对鸣禽种群产生了大范围的跨物种影响。在约1000公里的空间尺度下，种群同步化的潜在近因机制可能是：资源的天气驱动变异对种群产生的调控作用——这类变异尤其会影响繁殖成本。然而，先验预设的候选天气变量难以完全解释这一强烈的种间同步性：春季天气变量仅能解释1.4%[0.01–5.5]的同步性变异，而大范围冬季天气指数的贡献可能更高，但置信区间跨度较大（12%[0.3–37]）。未来研究可将该结果尺度上推至群落动态层面，以解析维持集合群落免于同步化的种内与种间补偿性种群统计过程。