Summary1. Estimating how much long-distance migrant populations spread out and mix during the non-breeding season (migratory connectivity) is essential for understanding and predicting population dynamics in the face of global change. 2. We quantify variation in population spread and inter-population mixing in long-distance, terrestrial migrant land-bird populations (712 individuals from 98 populations of 45 species, from tagging studies in the Neotropic and Afro-Palearctic flyways). We evaluate the Mantel test as a metric of migratory connectivity, and explore the extent to which variance in population spread can be explained simply by geography. 3. The mean distance between two individuals from the same population during the nonbreeding season was 743 km, covering 10-20% of the maximum width of Africa/South America. Individuals from different breeding populations tended to mix during the non-breeding season, although spatial segregation was maintained in species with relatively large non-breeding ranges (and, to a lesser extent, those with low population-level spread). A substantial amount of between-population variation in population spread was predicted simply by geography, with populations using non-breeding zones with limited land availability (e.g. Central America compared to South America) showing lower population spread. 4. The high levels of population spread suggest that deterministic migration tactics are not generally adaptive; this makes sense in the context of the recent evolution of the systems, and the spatial and temporal unpredictability of non-breeding habitat. 5. The conservation implications of generally low connectivity are that the loss (or protection) of any non-breeding site will have a diffuse but widespread effect on many breeding populations. Although low connectivity should engender population resilience to shifts in habitat (e.g. due to climate change), we suggest it may increase susceptibility to habitat loss. We hypothesize that, because a migrant species cannot adapt to both simultaneously, migrants generally may be more susceptible to population declines in the face of concurrent anthropogenic habitat and climate change.

How we manage farming and food systems to meet rising demand is pivotal to the future of biodiversity. Extensive field data suggest impacts on wild populations would be greatly reduced through boosting yields on existing farmland so as to spare remaining natural habitats. High-yield farming raises other concerns because expressed per unit area it can generate high levels of externalities such as greenhouse gas (GHG) emissions and nutrient losses. However, such metrics underestimate the overall impacts of lower-yield systems, so here we develop a framework that instead compares externality and land costs per unit production. Applying this to diverse datasets describing the externalities of four major farm sectors reveals that, rather than involving tradeoffs, the externality and land costs of alternative production systems can co-vary positively: per

Interviews are a widely used methodology in conservation research. They are flexible, allowing in‐depth analysis from a relatively small sample size and place the focus of research on the views of participants. While interviews are a popular method, several critiques have been raised in response to their use, including the lack of transparency in sampling strategy, choice of questions and mode of analysis. In this paper, we analyse the use of interviews in research aimed at making decisions for conservation. Through a structured review of 227 papers, we explore where, why and how interviews were used in the context of conservation decision making The review suggests that interviews are a widely used method for a broad range of purposes. These include gaining ecological and/or socio‐economic information on specific conservation issues, understanding knowledge, values, beliefs or decision‐making processes of stakeholders, and strengthening research design and output. The review, however, identifies a number of concerns. Researchers are not reporting fully on their interview methodology. Specifically, results indicate that researchers are: failing to provide a rationale as to why interviews are the most suitable method, not piloting the interviews (thus questions may be poorly designed), not outlining ethical considerations, not providing clear guides to analysis and not critically reviewing their use of interviews. Based on the results of the review, we provide a detailed checklist aimed at conservation researchers who wish to use interviews in their research (whether experienced in using the methodology or not), and journal editors and reviewers to ensure the robustness of interview methodology use.

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A recent paper claiming evidence of global insect declines achieved huge media attention, including claims of “insectaggedon” and a “collapse of nature.” Here, we argue that while many insects are declining in many places around the world, the study has important limitations that should be highlighted. We emphasise the robust evidence of large and rapid insect declines present in the literature, while also highlighting the limitations of the original study.

Aim The extent to which individuals from different breeding populations mix throughout the non‐breeding season (i.e. ‘migratory connectivity’) has important consequences for population dynamics and conservation. Given recent declines of long‐distance migrant birds, multipopulation tracking studies are crucial in order to assess the strength of migratory connectivity and to identify key sites en route. Here, we present the first large‐scale analysis of migration patterns and migratory connectivity in the globally near‐threatened European roller Coracias garrulus. Location Breeding area: Europe; passage area: Mediterranean, sub‐Saharan Africa, Arabian Peninsula; wintering area: southern Africa. Methods We synthesize new geolocator data with existing geolocator, satellite tag and ring recovery data from eight countries across Europe. We describe routes and stopover sites, analyse the spatial pattern of winter sites with respect to breeding origin and quantify the strength of connectivity between breeding and winter sites. Results We demonstrate the importance of the northern savanna zone as a stopover region and reveal the easterly spring loop (via Arabia) and leapfrog migration of rollers from eastern populations. Whilst there was some overlap between individuals from different populations over winter, their distribution was non‐random, with positive correlations between breeding and autumn/winter longitude as well as between pairwise distance matrices of breeding and winter sites. Connectivity was stronger for eastern populations than western ones. Main conclusions The moderate levels of connectivity detected here may increase the resilience of breeding populations to localized habitat loss on the winter quarters. We also highlight the passage regions crucial for the successful conservation of roller populations, including the Sahel/Sudan savanna for all populations, and the Horn of Africa/Arabian Peninsula for north‐eastern rollers.

Long-distance migratory bird populations are likely to be declining because of climate change shifting habitats or anthropogenic habitat loss [1], but this may be mediated by the size of the non-breeding area over which a population spreads (migratory spread), and migration distance (or number of stop-over sites). High migratory spread may make populations more resilient to climate change because they already encompass shifting habitats, but less resilient to uneven habitat loss that may not affect populations with low migratory spread [2] (Figure 1C). As migration distance increases so the probability of encountering a stop-over site with negative environmental change increases [3] (Figure 1D). Consequently, if habitat shift through climate change is the main driver of declines we predict more positive population trends for high spread migrants, but the reverse for outright habitat loss (Figure 1E); we also predict negative population trends for longer distance migrants (Figure 1F). But these relationships may vary between flyways, which differ profoundly in their climate variation, human population change and geography. Here we show that climate change may be more important in Neotropic migrant population declines whereas habitat loss may be more important in the Afro-Palearctic.

The rapid growth of online tools to communicate scientific research raises the important question of whether online attention is associated with citations in the scholarly literature. The Altmetric Attention Score (AAS) quantifies the attention received by a scientific publication on various online platforms including news, blogs and social media. It has been advanced as a rapid way of gauging the impact of a piece of research, both in terms of potential future scholarly citations and wider online engagement. Here, we explore variation in the AAS of 2677 research articles published in 10 ornithological journals between 2012 and 2016. On average, AAS increased sevenfold in just five years, primarily due to increased activity on Twitter which contributed 75% of the total score. For a subset of 878 articles published in 2014, including an additional 323 ornithology articles from non-specialist journals, an increase in AAS from 1 to 20 resulted in a predicted 112% increase in citation count from 2.6 to 5.5 citations per article. This effect interacted with journal impact factor, with weaker effects of AAS in higher impact factor journals. Our results suggest that altmetrics (or the online activity they measure), as well as complementing traditional measures of scholarly impact in ornithology such as citations, may also anticipate or even drive them.