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The DDT-induced effects, eggshell thinning and breeding failure in Peregrine Falcon (Falco peregrinus)populations were reverted with restrictions on the use of the compound from the 1970s, and in most studied populations, the eggshell thickness is back to normal. In Greenland, a previous study of eggshell thinning in Peregrines found that shells had not yet reached pre-DDT levels. In this study, we extend the time series and reinterpret shell thinning data for 196 clutches covering a 45-year time span (1972–2017). There was a significant (P<0.001) increase in the eggshell thickness of 0.23% per year. This corresponds to a change in eggshell thinning from 14.5% to 5.4% in 2017 compared to the pre-DDT mean. With the current rate of change, pre-DDT shell thickness is predicted to be reached around the year 2034. However, a few clutches are still below the critical limit. The relatively slower recovery of the shell thickness in the Greenland population is likely indicative of the slower phasing out of DDT in the Greenlandic Peregrines’ wintering grounds in Latin America. The shell thinning in the Greenlandic population probably never crossed the 17% threshold associated with population declines, contrary to the populations in many other parts of the world.

The methodology and results of Monte Carlo (Tier 2) uncertainty analysis of the Danish Greenhouse Gas (GHG) inventory for base year 1990 and most recent year 2008 are presented. The analysis covers 100% of the total net Danish GHG emissions and removals, excluding LULUCF. Methodological procedures such as random sampling of uncertain parameters and parameter correlation between years are explained. Uncertainties in activity data and emission factors are given for all sectors, Input data are assumed to have log-normal probability distributions, represented by median values and 95% confidence interval uncertainties. The total uncertainty levels for GHG emissions, expressed as 95% confidence intervals, are 4.1 and 5.3% for Tier 1 and Tier 2, respectively. Uncertainties in the trend are 2.4 and 6.9% for Tier 1 and Tier 2, respectively. The most influential sources from the Tier 2 analysis to the total uncertainty are CH4from solid waste disposal on land (4.4%), N2O from leaching (3.0%), N2O from synthetic fertilizer (2.0%), and N2O and CH4from manure management, each with 1.6%. Tier 1 and Tier 2 uncertainties in levels and trends are comparable to seven European countries that have performed a Tier 2 uncertainty analysis.

SummaryPollinating insects form a key component of European biodiversity, and provide a vital ecosystem service to crops and wild plants. There is growing evidence of declines in both wild and domesticated pollinators, and parallel declines in plants relying upon them. The STEP project (Status and Trends of European Pollinators, 2010–2015, www.step-project.net) is documenting critical elements in the nature and extent of these declines, examining key functional traits associated with pollination deficits, and developing a Red List for some European pollinator groups. Together these activities are laying the groundwork for future pollinator monitoring programmes. STEP is also assessing the relative importance of potential drivers of pollinator declines, including climate change, habitat loss and fragmentation, agrochemicals, pathogens, alien species, light pollution, and their interactions. We are measuring the ecological and economic impacts of declining pollinator services and floral resources, including effects on wild plant populations, crop production and human nutrition. STEP is reviewing existing and potential mitigation options, and providing novel tests of their effectiveness across Europe. Our work is building upon existing and newly developed datasets and models, complemented by spatially-replicated campaigns of field research to fill gaps in current knowledge. Findings are being integrated into a policy-relevant framework to create evidence-based decision support tools. STEP is establishing communication links to a wide range of stakeholders across Europe and beyond, including policy makers, beekeepers, farmers, academics and the general public. Taken together, the STEP research programme aims to improve our understanding of the nature, causes, consequences and potential mitigation of declines in pollination services at local, national, continental and global scales.