Summary1. Invasive alien plants have serious economic and ecological impacts, for example, by displacing native plants and invertebrates, and their management is often costly and ineffective in the long term. Classical biological control using specialized, coevolved natural enemies from the native region of the invader is often advocated as a preferred alternative to chemical and mechanical control, but there is a lack of quantitative assessment of control of the target species and subsequent establishment of native vegetation and invertebrates. 2. Meta-analyses were carried out combining the results of 61 published studies (2000)(2001)(2002)(2003)(2004)(2005)(2006)(2007)(2008)(2009)(2010)(2011) that quantified the impact of classical biocontrol at the level of individual target plants, target populations or non-target vegetation. Factors associated with the control programmes (invasive region, native region, plant growth form, target longevity, control agent guild, taxonomy and study duration) were analysed to identify patterns in control success. 3. On average, biocontrol agents significantly reduced plant size (28 ± 4%), plant mass (37 ± 4%), flower and seed production (35 ± 13% and 42 ± 9%, respectively) and target plant density (56 ± 7%). Beetles in the Chrysomelidae and Curculionidae families were more effective at reducing plant size than other groups. 4. Non-target plant diversity significantly increased by 88 ± 31% at sites where biocontrol agents were released, but it was largely unclear whether the replacement plant species were native or invasive. 5. Synthesis and applications. The number of studies that provide quantitative indications of the effectiveness of biocontrol and the response of non-target taxa has increased over the past decade, but remains small compared to the total number of publications on the classical biocontrol of invasive plants. Nonetheless, this study demonstrates the positive impacts of classical biocontrol and the re-establishment of native plants in a broad range of systems and establishes the value of classical biocontrol for the control of invasive alien plants. The Chrysomelidae and Curculionidae families were the most effective agents and we recommend these be prioritized in cases where potential agents of different taxa have also been identified. In addition, data on the recovery of native plant species and the invertebrate community remain sparse and it is recommended that future studies report the identity of plant species that replace target species as well as invertebrate community responses.

Each year, billions of songbirds cross large ecological barriers during their migration. Understanding how they perform this incredible task is crucial to predict how global change may threaten the safety of such journeys. Earlier studies based on radar suggested that most songbirds cross deserts in intermittent flights at high altitude, stopping in the desert during the day, while recent tracking with light loggers suggested diurnal prolongation of nocturnal flights and common non-stop flights for some species. We analyzed light intensity and temperature data obtained from geolocation loggers deployed on 130 individuals of ten migratory songbird species, and show that a large variety of strategies for crossing deserts exists between, but also sometimes within species. Diurnal stopover in the desert is a common strategy in autumn, while most species prolonged some nocturnal flights into the day. Non-stop flights over the desert occurred more frequently in spring than in autumn, and more frequently in foliage gleaners. Temperature recordings suggest that songbirds crossed deserts with flight bouts performed at various altitudes according to species and season, along a gradient ranging from low above ground in autumn to probably >2000 m above ground level, and possibly at higher altitude in spring. High-altitude flights are therefore not the general rule for crossing deserts in migrant songbirds. We conclude that a diversity of migration strategies exists for desert crossing among songbirds, with variations between but also within species.

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Background Landfills are a major subsidy for some animals, with implications for their life history and demography. Gulls feed extensively on food from landfills and closures are expected to have ecological consequences, but how this influences movement ecology is virtually unknown. Methods We used GPS-tracking to quantify foraging behaviour and habitat choice of lesser black-backed gulls (Larus fuscus) breeding at two colonies before and after closure of two nearby landfills. Results Following closure, gulls from both colonies travelled further and for longer to forage. Gulls also changed habitat selection, although this differed by colony - birds from one colony shifted to agricultural habitats, while at the other, increased their use of urban areas. These behavioural responses had no effect on adult body condition but hint at potential direct effects of higher foraging costs and indirect impacts by shifting to new habitats. Conclusions Our results demonstrate how landfill availability influences gull foraging movements and habitat selection. We also emphasize the value of biologging to detect rapid behavioural responses in contrast to more conventional demographic approaches, which is especially important for animals that spend the majority of their lives away from direct observation.

1. Wind energy generation has become an important means to reduce reliance on fossil fuels and mitigate against human-induced climate change, but could also represent a significant human-wildlife conflict. Airborne taxa such as birds may be particularly sensitive to collision mortality with wind turbines, yet the relative vulnerability of species' populations across their annual life cycles has not been evaluated.2. Using GPS telemetry, we studied the movements of lesser black-backed gulls Larus fuscus from three UK breeding colonies through their annual cycle. We modelled the distance travelled by birds at altitudes between the minimum and maximum rotor sweep zone of turbines, combined with the probability of collision, to estimate sensitivity to collision. Sensitivity was then combined with turbine density (exposure) to evaluate spatio-temporal vulnerability.3. Sensitivity was highest near to colonies during the breeding season, where a greater distance travelled by birds was in concentrated areas where they were exposed to turbines. 4. Consequently, vulnerability was high near to colonies but was also high at some migration bottlenecks and wintering sites where, despite a reduced sensitivity, exposure to turbines was greatest. Synthesis and applications.Our framework combines bird-borne telemetry and spatial data on the location of wind turbines to identify potential areas of conflict for migratory populations throughout their annual cycle. This approach can aid the wind farm planning process by: (a) providing sensitivity maps to inform wind farm placement, helping minimize impacts; (b) identifying areas of high vulnerability where mitigation warrants exploration; (c) highlighting potential cumulative impacts of developments over international boundaries and (d) informing the conservation status of species at protected sites. Our methods can identify pressures and linkages for populations using effect-specific metrics that are transferable and could help resolve other human-wildlife conflicts.