Evaluating the effectiveness of conservation funding is crucial for correct allocation of limited resources. Here we used bird monitoring data to assess the effects of long-term conservation investment in a Natura 2000 (N2000) bird protection area (PA), which during two decades benefited from protection regulations, conservation projects, and agri-environment schemes. Variation between
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a b s t r a c tAfforestation of agricultural land is increasingly used to deliver environmental benefits, but their effects on biodiversity remain poorly understood. This paper tests the hypothesis that afforestation changes predation processes in surrounding farmland, examining how the characteristics and landscape context of forest plantations affect predator (birds and mammalian carnivores) and key prey (rabbits and hares) abundances, and bird nest predation rates in Iberian cereal-steppes. Lagomorphs and predators were surveyed in fallow fields around 50 forest plantations, where predation rates were estimated using artificial nests set at 0, 100, 200 and 300 m from the forest edge. Recent plantations structurally similar to sparse (oak) or dense (pine) shrublands were associated with the highest hare and rabbit abundances, respectively, whereas both species avoided landscapes with high eucalyptus cover. In contrast, mature eucalyptus plantations showed strong positive effects on typical nest predators such as corvids and carnivores. Open farmland fragmentation favoured the abundance of lagomorphs and carnivores. Despite these effects and the high predation rate on artificial nests (49%), there was neither evidence for increased predation near plantation edges nor higher predation in fields with more lagomorphs and predators. However, predation tended to increase with cover by young oak plantations and overall forest plantation cover, to decrease with eucalyptus cover at both the local and landscape scales, and to peak in landscapes with intermediate edge densities. These results suggest that afforestation may have strong effects on bird nest predation rates by changing landscape composition and configuration, rather than by inducing local increases in predator and prey populations. Nevertheless, increased abundances of generalist predators associated with forest plantations may still be considered of conservation concern, thus supporting the recommendation for strongly restricting afforestation in areas important for open grassland birds. Where this is unavoidable, monitoring should be undertaken to provide early signals for bird population declines associated with predator increases, eventually triggering conservation action such as predator exclusion or removal.
In Iberian cereal-steppes, decoupling of payments from current production levels through the Single Farm Payment raised concerns regarding the potential for land abandonment and replacement of sheep by cattle, with eventual negative consequences for declining grassland birds. This study addressed this issue by analysing the responses of five grassland bird species of conservation concern to spatial land use gradients, which are expected to reflect changes potentially associated with the CAP reform. Our results show that both habitat fragmentation and grazing regimes were major drivers of breeding bird densities, though responses to these factors were species-specific. Thekla larks were most abundant in landscapes with small grassland patches and high edge density, whereas calandra larks were abundant only in large expanses of continuous open farmland habitat. Little bustard and short-toed lark densities declined in highly fragmented landscapes, but they appeared to tolerate or even benefit from low to moderate levels of open habitat fragmentation. Corn buntings were little affected by landscape patterns. At the field scale, little bustard and corn bunting densities were highest in fields grazed by cattle, whereas short-toed larks were mostly associated with sheep pastures. Short-toed larks and Thekla larks were most abundant in old fallow fields where cattle was largely absent, whereas corn buntings showed the inverse pattern. These results confirm the view that the same agricultural policies may be favourable for some species of conservation concern but detrimental to others, and so they cannot be assumed to bring uniform conservation benefits.
Aim: Power lines can represent an important source of bird mortality through collision. The identification of more susceptible species, in terms of expected populationlevel impacts, requires detailed biological and mortality information that is often difficult to obtain. Here, we propose a species prioritization method based on relatively easily accessed information, aimed to identify both species and areas with the potentially highest extinction risk due to collision with power lines.Location: As a case study, we applied this method to the communities of resident breeding birds of Spain and Portugal.Methods: For each considered species, the method takes into account the morphobehavioural susceptibility to collision with power lines, the susceptibility to extinction and the spatial exposure to collision with power lines. Results:Our method highlighted that the most susceptible species were large, longlived and slow-reproducing birds, often habitat specialists with hazardous behavioural traits (especially flight height and flocking flight), with high spatial exposure to collision risk with power lines and unfavourable conservation status. Based on the distribution ranges of these species, we produced a map of hotspots for extinction risk due to collision of such priority species for each country. These areas should be considered a priority for the implementation of mitigation measures including route planning and wire marking. Main conclusions:Overall, the proposed method can be applied to any bird community in any geographic area of the world where information on power-line distribution and published information on species traits, distribution and conservation status is available, generating valuable lists of both priority species and areas in which collision risk with power lines can potentially produce local or even global extinctions. K E Y W O R D S collision, exposure, extinction risk, life-history traits, power lines, susceptibility B I OS K E TCH This research was conducted by REN Biodiversity Chair (MD, RCM and FM), a research lab at CIBIO-InBIO and CEABN-InBIO, with the support of JMAM, MP and RB. REN Biodiversity Chair addresses several topics related to the impact of power lines on biodiversity, including bird mortality by collision. Author contributions: F.M. conceived the idea; M.D., R.C.M., J.M.A.M., M.P. and R.B. collected the data; M.D., R.C.M., M.P. and F.M. analysed the data; M.D. and F.M. led the writing; R.C.M., J.M.A.M., M.P. and R.B. contributed to writing and revisions. SUPPORTING INFORMATION Additional supporting information may be found online in the Supporting Information section at the end of the article. How to cite this article: D'Amico M, Martins RC, Álvarez-Martínez JM, Porto M, Barrientos R, Moreira F. Bird collisions with power lines: Prioritizing species and areas by estimating potential population-level impacts. Divers Distrib. 2019;25:975-982. https://doi.
Background Lack of suitable analytical software and computational power constrains the comprehension of animal movement. In particular, we are aware of no tools allowing simulating spatially-explicit multistate Markovian movements constrained to linear features or conditioned by landscape heterogeneity, which hinders movement ecology research in linear/dendritic (e.g. river networks) and heterogeneous landscapes. SiMRiv is a novel, fast and intuitive R package we designed to fill such gap. It does so by allowing continuous-space mechanistic spatially-explicit simulation of multistate Markovian individual movements incorporating landscape bias on local behavior. Results We present SiMRiv and its main functionalities, illustrate its simulation capabilities and easy-of-use, and discuss its limitations and potential improvements. We further provide examples of use and a preliminary evaluation, using real and simulated data, of a parameter approximation experimental method. SiMRiv allowed us to generate increasingly complex movements of three theoretical species (aquatic, semiaquatic and terrestrial), showing the effects of input parameters and water-dependence on emerging movement patterns, and to parameterize a high-frequency simulation model from real, low-frequency movement (telemetry) data. Typical running times for conducting 1000 simulations with 10,000 steps each, of two-state movement trajectories in a river network, were of ca. 3 min in an Intel Core i7 CPU X990 @ 3.47 GHz. Conclusions SiMRiv allows simulation of movements constrained to linear habitats or conditioned by landscape heterogeneity, therefore enhancing the application of movement ecology to linear/dendritic and heterogeneous landscapes. Importantly, the software is flexible enough to be used in linear, heterogeneous, as well as homogeneous landscapes. Using the same software, algorithm and approach, one can therefore use SiMRiv to study the movement of different organisms in a variety of landscapes, facilitating comparative research. SiMRiv balances ease and speed with high realism of the movement models obtainable, constituting a fast, powerful, yet intuitive tool, which should contribute exploring several movement-related questions. Its applications depart from the generation of mechanistic null movement models, up to population level (e.g. landscape connectivity) analyses, holding potential for all fields requiring the simulation of random trajectories. Electronic supplementary material The online version of this article (10.1186/s40462-019-0154-8) contains supplementary material, which is available to authorized users.
Mechanical clearing of understory vegetation is increasingly used in EuroMediterranean forests to reduce fire hazard, yet its long-term consequences for biodiversity remain poorly understood. This study analysed the influence of time since understory management and management frequency, on herbaceous species richness, cover and composition, functional richness and composition, and richness and cover within functional groups (life and growth forms, dispersal strategy, clonality, and plant height), using a chronosequence of cork oak (Quercus suber) stands spanning about 70 years. Overall species richness was virtually constant over time, but the richness of species with annual life form and plasticity in height was much higher in recently and recurrently treated stands; the opposite was found for perennial (mainly hemicryptophytes and chamaephytes), tussock-forming and clonal species richness, and functional richness. Overall herbaceous cover and that of annual, semi-basal, non-clonal and plastic species (in height) were favoured by recent and recurrent fuel treatments; cover by perennial (hemicryptophytes and chamaephytes), short basal, tussock-forming, and clonal species tended to increase for [10-20 years after management, and declined with management frequency. There was a marked shift in species and functional composition associated with time since understory management and management frequency. These findings suggest that widespread fuel management at \10 year intervals may shift understory herb communities to early-successional stages, impairing the persistence of species and functional groups recovering slowly after disturbance. Fuel management needs to balance the dual goals of Electronic supplementary material The online version of this article (
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