United Kingdom Butterfly Monitoring Scheme: collated indices 2022

Collated indices are a relative measure of butterfly abundance across sites monitored as part of the UK Butterfly Monitoring Scheme. Data from all survey sites (standard UKBMS transects, Wider Countryside Survey transects and targeted species surveys such as timed, larval web and egg counts) are used in the calculation of these indices. The statistics are presented as log10 values. These values are centred round an arbitrary value of 2 as a mean for the time series in order to help show which years are below or above average. Collated indices are calculated annually for each individual butterfly species that has been recorded on five or more sites in that year. Indices are calculated at UK level and at individual country level for England, Scotland, Wales and Northern Ireland where sufficient data are available. Based on this criterion, collated indices have been calculated for the entire time series from 1976 (UK, England and Wales), 1979 (Scotland) and 2004 (Northern Ireland) to the current year for the majority of species, but for some rarer species this has not been possible in some years, particular those in the first part of the time series. Collated indices are calculated using a log-linear model incorporating individual site indices from all monitored sites across the UK or country for a given species in a given year. The number of sites for each species ranges from 5 to several hundred or more and fluctuates from year to year. By 2010 almost 2,000 sites were monitored in total across the UK, with this number rising to more than 3,000 over the next decade. Collated indices are calculated so that we can determine how butterfly populations are changing over time across the UK. This data can be used, for example, to determine where to target conservation efforts and more generally the condition of the UK countryside. Butterflies are recognised as important indicators of biodiversity and environmental change, for example in UK and country Biodiversity Indicators, and have been used in numerous studies of the impacts of climate and habitat change on biodiversity. The UK Butterfly Monitoring Scheme is organized and funded by Butterfly Conservation (BC), the UK Centre for Ecology & Hydrology (UKCEH), the British Trust for Ornithology (BTO), and the Joint Nature Conservation Committee (JNCC). The UKBMS is indebted to all volunteers who contribute data to the scheme. This work was supported by the Natural Environment Research Council award number NE/R016429/1 as part of the UK-SCAPE programme delivering National Capability.

汇编的指数是对英国蝴蝶监测计划所监测地点蝴蝶丰富度的相对度量。计算这些指数所用的数据涵盖了所有调查地点（标准英国蝴蝶监测计划样带、更广泛乡村调查样带以及针对特定物种的调查，如定时调查、幼虫网和卵计数等）。统计数据以常用对数（log10）形式呈现。这些数值以2作为时间序列的平均值进行标准化，以便展示哪些年份低于或高于平均水平。汇编的指数是针对当年在五个或更多地点记录的每一个蝴蝶物种按年度计算的。指数在英国层面及英格兰、苏格兰、威尔士和北爱尔兰等国家层面进行计算，前提是有足够的数据。基于这一标准，汇编的指数已经计算了从1976年（英国、英格兰和威尔士）、1979年（苏格兰）至2004年（北爱尔兰）至今的整个时间序列，对于大多数物种而言，但对于一些稀有物种，在时间序列的前期某些年份并未实现，尤其是在时间序列的开端。汇编的指数通过整合来自英国或特定国家在特定年份所有监测地点的个别地点指数，使用对数线性模型进行计算。每个物种的地点数量从5个到数百个甚至更多，并逐年波动。到2010年，英国共监测了总计近2000个地点，而在接下来的十年中，这一数字上升至超过3000个。汇编的指数的计算旨在确定英国蝴蝶种群随时间的变化情况。这些数据可用于确定保护努力的靶向地点，以及更广泛地了解英国乡村的状况。蝴蝶被认为是生物多样性和环境变化的敏感指标，例如在英国和国家生物多样性指标中，以及被广泛应用于气候和栖息地变化对生物多样性影响的研究中。英国蝴蝶监测计划由蝴蝶保护协会（BC）、英国生态与水文学中心（UKCEH）、英国鸟类信托基金会（BTO）和联合自然保护委员会（JNCC）组织并资助。英国蝴蝶监测计划对为该计划提供数据的所有志愿者表示衷心的感谢。本研究得到自然环境研究委员会（NERC）项目资助，资助编号为NE/R016429/1，作为英国-SCAPE项目的一部分，旨在提升国家能力。