Articulating citizen science, semi-automatic identification and free web services for long-term acoustic monitoring: examples from France and UK

Monitoring biodiversity over large spatial and temporal scales is crucial for assessing the impact of global changes and environmental mitigation measures. Bats often have high conservation prioritisation owing to their trophic position, habitat associations and threat level, and many have dedicated management plans. However, poor knowledge of species' ecology, identification issues and surveying challenges mean that large-scale monitoring to produce required distribution and abundance information is less developed than for some other taxa. Exciting possibilities applicable to professional and citizen science are offered by new recording techniques and methods of semi-automated species recognition based on sound detection. Static detectors deployed to record bats throughout whole nights have been recommended for standardised acoustic monitoring but until recently cost and lack of software to support the analyses of such data has prohibited wide uptake. Such monitoring schemes have recently been deployed in both Britain and France allowing the fast and standardized collection of millions of bat records together with very interesting data on non-targeted taxa such as bush-crickets. Such data management led us to develop generic and open tools: (1) the Tadarida software toolbox providing a generic detection and classification of sound events, and (2) an open dedicated web portal (www.vigiechiro.herokuapp.com) to allow participants to manage and upload their data, then being processed trough Tadarida to get a quick feedback on the content of the data. We demonstrate how such data can accurately describe pronounced ecological patterns for numerous species at different scales: spatial variation in activity as a proxy for relative abundance, habitat selection and phenology of seasonal and nocturnal activity. If maintained in the long term, such schemes will also greatly improve estimates of species temporal trends and hence the assessment of conservation priorities. The feedback produced by these two monitoring schemes allows us the opportunity to provide recommendations for the sustainability of long-term acoustic monitoring of bats. These include a database that is adaptively managed to allow all raw data to be re-analysed every time automatic identification makes significant progress, while keeping the link with expert validation to ensure consistency in the semi-automated process. More importantly, there are real benefits of developing long-term acoustic monitoring within a collaborative framework. Specifically, (1) for collaboration among bat scientists for the collection of reference sound data, because diversity and quantity of the reference library remains a limiting factor for automatic identification, and (2) for work on bats to consider the wider acoustic monitoring of other species groups by working with other zoologists to share resources and costs

Accounting for automated identification errors in acoustic surveys

R scripts and datset used in the pape

Weed control method drives conservation tillage efficiency on farmland breeding birds

International audienceCrops management is known to influence biodiversity, especially conservation tillage (CT, no-till) often found as a positive method compared to conventional tillage (T, inversion of soil) but without controlling for underlying farming practices. There are many ways to perform CT, in particular concerning the control of weeds, but few studies have taken into account these methods, which could explain the lack of consensus about the effect of CT compared to T. We tested differences in breeding birds abundance between CT and T while accounting for weed control methods in oilseed rape and wheat CT fields. During the intercrop period, one CT system used a cover crop to control weeds (CTcc), the other used herbicides (CTh) and the control (T) system only used a tillage. We made CTcc/T and CTh/T comparisons by sampling bird abundance (respectively 49 CTcc/51 T and 30 CTh/33 T point counts). We show substantial differences between CTcc/T and CTh/T comparisons as we detected greater bird abundances in CTcc than T for 5 species (2.3–4.1 times more individuals) and a lower abundance in CTh than T for 2 species (2.1–2.2 times less individuals). Our results demonstrate the importance to account for system features to ensure the CT efficiency for farmland birds, declining strongly in Europe since 1980 (−55 to −67%). Results also highlight an even more negative impact of herbicides than tillage, showing that stopping tillage to intensify herbicide use is not a promising way

Data from: Tillage and herbicide reduction mitigate the gap between conventional and organic farming effects on foraging activity of insectivorous bats

The increased use of pesticides and tillage intensification is known to negatively affect biodiversity. Changes in these agricultural practices such as herbicide and tillage reduction have variable effects among taxa, especially at the top of the trophic network including insectivorous bats. Very few studies compared the effects of agricultural practices on such taxa, and overall, only as a comparison of conventional versus organic farming without accurately accounting for underlying practices, especially in conventional where many alternatives exist. Divergent results founded in these previous studies could be driven by this lack of clarification about some unconsidered practices inside both conventional and organic systems. We simultaneously compared, over whole nights, bat activity on contiguous wheat fields of one organic and three conventional farming systems located in an intensive agricultural landscape. The studied organic fields (OT) used tillage (i.e., inversion of soil) without chemical inputs. In studied conventional fields, differences consisted of the following: tillage using few herbicides (T), conservation tillage (i.e., no inversion of soil) using few herbicides (CT), and conservation tillage using more herbicide (CTH), to control weeds. Using 64 recording sites (OT = 12; T = 21; CT = 13; CTH = 18), we sampled several sites per system placed inside the fields each night. We showed that bat activity was always higher in OT than in T systems for two (Pipistrellus kuhlii and Pipistrellus pipistrellus) of three species and for one (Pipistrellus spp.) of two genera, as well as greater species richness. The same results were found for the CT versus T system comparison. CTH system showed higher activity than T for only one genus (Pipistrellus spp.). We did not detect any differences between OT and CT systems, and CT showed higher activity than CTH system for only one species (Pipistrellus kuhlii). Activity in OT of Pipistrellus spp. was overall 3.6 and 9.3 times higher than CTH and T systems, respectively, and 6.9 times higher in CT than T systems. Our results highlight an important benefit of organic farming and contrasted effects in conventional farming. That there were no differences detected between the organic and one conventional system is a major result. This demonstrates that even if organic farming is presently difficult to implement and requires a change of economic context for farmers, considerable and easy improvements in conventional farming are attainable, while maintaining yields and approaching the ecological benefits of organic methods

Tillage and herbicide reduction mitigate the gap between conventional and organic farming effects on foraging activity of insectivorous bats

The increased use of pesticides and tillage intensification is known to negatively affect biodiversity. Changes in these agricultural practices such as herbicide and tillage reduction have variable effects among taxa, especially at the top of the trophic network including insectivorous bats. Very few studies compared the effects of agricultural practices on such taxa, and overall, only as a comparison of conventional versus organic farming without accurately accounting for underlying practices, especially in conventional where many alternatives exist. Divergent results founded in these previous studies could be driven by this lack of clarification about some unconsidered practices inside both conventional and organic systems. We simultaneously compared, over whole nights, bat activity on contiguous wheat fields of one organic and three conventional farming systems located in an intensive agricultural landscape. The studied organic fields (OT) used tillage (i.e., inversion of soil) without chemical inputs. In studied conventional fields, differences consisted of the following: tillage using few herbicides (T), conservation tillage (i.e., no inversion of soil) using few herbicides (CT), and conservation tillage using more herbicide (CTH), to control weeds. Using 64 recording sites (OT = 12; T = 21; CT = 13; CTH = 18), we sampled several sites per system placed inside the fields each night. We showed that bat activity was always higher in OT than in T systems for two (Pipistrellus kuhlii and Pipistrellus pipistrellus) of three species and for one (Pipistrellus spp.) of two genera, as well as greater species richness. The same results were found for the CT versus T system comparison. CTH system showed higher activity than T for only one genus (Pipistrellus spp.). We did not detect any differences between OT and CT systems, and CT showed higher activity than CTH system for only one species (Pipistrellus kuhlii). Activity in OT of Pipistrellus spp. was overall 3.6 and 9.3 times higher than CTH and T systems, respectively, and 6.9 times higher in CT than T systems. Our results highlight an important benefit of organic farming and contrasted effects in conventional farming. That there were no differences detected between the organic and one conventional system is a major result. This demonstrates that even if organic farming is presently difficult to implement and requires a change of economic context for farmers, considerable and easy improvements in conventional farming are attainable, while maintaining yields and approaching the ecological benefits of organic methods

Estimating habitat loss due to wind turbine avoidance by bats: Implications for European siting guidance

International audienceWind energy is rapidly growing as a renewable source of energy but is not neutral for wildlife, especially bats. Whereas most studies have focused on bat mortality through collision, very few have quantified the loss of habitat use resulting from the potential negative impact of wind turbines, and none of them for hub heights higher than 55 m. Such impacts could durably affect populations, creating a need for improvement of knowledge to integrate this concern in implementation strategies. We quantified the impact of wind turbines at different distances on the activity of 11 bat taxa and 2 guilds. We compared bat activity at hedgerows (207 sites) located at a distance of 0–1000 m from wind turbines (n = 151) of 29 wind farms in an agricultural region in the autumn (overall 193,980 bat passes) using GLMMs. We found a significant negative effect of proximity to turbines on activity for 3 species (Barbastella barbastellus, Nyctalus leisleiri, Pipistrellus pipistrellus), 2 species-groups (Myotis spp., Plecotus spp.) and 2 guilds (fast-flying and gleaner). Bat activity within 1000 m of wind turbines by gleaners and fast-flying bats is reduced by 53.8% and 19.6%, respectively. Our study highlighted that European recommendations (at least 200 m from any wooded edge) to limit mortality events likely strongly underestimate the loss of bat activity. The current situation is particularly worrying, with 89% of 909 turbines established in a region that does not comply with recommendations, which themselves are far from sufficient to limit the loss of habitat use

Dataset for "Disentangling mechanisms responsible for wind energy effects on European bats"

Data used in the study "Disentangling mechanisms responsible for wind energy effects on European bats". site = ID attributed to the studied site ; ID_Parc = ID attributed to the studied wind farm ; night = date of the sampling ; SM4 = ID attributed to the recorder ; NbWT_1500m = number of wind turbines in a 1500m buffer ; Dist_WT = distance to the nearest wind turbine ; Dist_water = distance to the nearest water body or water course ; Dist_forest = distance to the nearest forest ; avg_temp = average temperature of the night ; Prev_wind_mod1 = prevailing wind direction of the night ; count_prev_wind22.5 = number of hours during which the wind direction was close (± 22.5°) to the prevailing wind direction (mode) of the night ; angle = angle between the axis wind-turbine - detector and the north direction ; MES_year = year of commissioning of the nearest wind turbines ; Model = model of the nearest wind turbine ; Rotor_diameter = diameter of the rotor of the nearest wind turbine ; Hub_height = height of the hub of the nearest wind turbine ; ID_WT = ID attributed to the nearest wind turbin

Drivers of bat activity at wind turbines advocate for mitigating bat exposure using multicriteria algorithm-based curtailment

Wind turbine development is growing exponentially and faster than other sources of renewable energy worldwide. While multi-turbine facilities have small physical footprint, they are not free from negative impacts on wildlife. This is particularly true for bats, whose population viability can be threatened by wind turbines through mortality events due to collisions. Wind turbine curtailment (hereafter referred to as “blanket curtailment”) in non-winter periods at low wind speeds and mild temperatures (i.e. when bats are active and wind energy production is low) can reduce fatalities, but show variable and incomplete effectiveness because other factors affect fatality risks including landscape features, rain, turbine functioning, and seasonality. The combined effects of these drivers, and their potential as criteria in algorithm-based curtailment, have so far received little attention. We compiled bat acoustic data recorded over four years at 34 wind turbine nacelles in France from post-construction regulatory studies, including 8619 entire nights (251 ± 58 nights per wind turbine on average). We modelled nightly bat activity in relation to its multiple drivers for three bat guilds, and assessed whether curtailment based on algorithm would be more efficient to limit bat exposure than blanket curtailment based on various combinations of unique wind speed and temperature thresholds. We found that landscape features, weather conditions, seasonality, and turbine functioning determine bat activity at nacelles. Algorithm-based curtailment is more efficient than blanket curtailment, and has the potential to drastically reduce bat exposure while sustaining the same energy production. Compared to blanket curtailment, the algorithm curtailment reduces average exposure by 20 to 29 % and 7 to 12 % for the high-risk guilds of long- and mid-range echolocators, and by 24 to 31 % for the low-risk guild of short-range echolocators. These findings call for the use of algorithm curtailment as both power production and biodiversity benefits will be higher in most situations

Projet MITI· PLUM : Mitigation de la pression Lumineuse : vers l’adaptation en temps réel de l’éclairage public aux enjeux écologiques transitoires du PNR de Brière

La fragmentation des habitats par la lumière artificielle nocturne est une préoccupation centrale parmi les effets de la lumière artificielle sur la biodiversité, créant notamment des modifications dans l’utilisation spatiale des habitats qui peuvent compromettre à terme la réalisation du cycle de vie des espèces — par exemple l’accès aux sites de repos (haltes migratoires), aux partenaires ou aux sites de reproduction. À l’heure actuelle, les outils dont se dotent les territoires pour juguler les effets écologiques de la pollution lumineuse sont construits sur une connaissance figée de la pression lumineuse et sur des inventaires d’espèces réputées nocturnes, sans considération des temporalités de leur cycle de vie. Pourtant, de nouveaux possibles sont ouverts par l’utilisation de plus en plus massive des luminaires LED en éclairage public : gradation ou extinction, voire adaptation en temps réel — par alertes ou par télégestion – lorsque des conditions météorologiques spécifiques amplifiant largement la pression lumineuse rencontrent, dans l’espace et dans le temps, des enjeux écologiques transitoires majeurs. Ce sont ces possibles que le projet MITI·PLUM propose d’explorer, dans un territoire de première importance au regard de l’enjeu “oiseaux migrateurs” : le Parc naturel régional de Brière. Du point de vue méthodologique, un réseau de photomètres permettra le suivi en temps réel de la pression lumineuse et sa mise en lien avec les paramètres météorologiques. Le couplage de ces données avec (i) les connaissances spatio-temporellespréexistantes sur les enjeux écologiques transitoires propres au territoire et (ii) les connaissances socio-spatiales quant à l’acceptation de mesures de réduction de la pression lumineuse permettra la définition interdisciplinaire de règles d’alerte sur les “moments et zones à enjeux lumière artificielle”. Enfin, la production d’un dashboard permettra de relayer ces alertes auprès du PNR de Brière — partenaire de ce projet — et des maires, décisionnaires finaux en matière de gestion de l’éclairage public

Projet MITI· PLUM : Mitigation de la pression Lumineuse : vers l’adaptation en temps réel de l’éclairage public aux enjeux écologiques transitoires du PNR de Brière

La fragmentation des habitats par la lumière artificielle nocturne est une préoccupation centrale parmi les effets de la lumière artificielle sur la biodiversité, créant notamment des modifications dans l’utilisation spatiale des habitats qui peuvent compromettre à terme la réalisation du cycle de vie des espèces — par exemple l’accès aux sites de repos (haltes migratoires), aux partenaires ou aux sites de reproduction. À l’heure actuelle, les outils dont se dotent les territoires pour juguler les effets écologiques de la pollution lumineuse sont construits sur une connaissance figée de la pression lumineuse et sur des inventaires d’espèces réputées nocturnes, sans considération des temporalités de leur cycle de vie. Pourtant, de nouveaux possibles sont ouverts par l’utilisation de plus en plus massive des luminaires LED en éclairage public : gradation ou extinction, voire adaptation en temps réel — par alertes ou par télégestion – lorsque des conditions météorologiques spécifiques amplifiant largement la pression lumineuse rencontrent, dans l’espace et dans le temps, des enjeux écologiques transitoires majeurs. Ce sont ces possibles que le projet MITI·PLUM propose d’explorer, dans un territoire de première importance au regard de l’enjeu “oiseaux migrateurs” : le Parc naturel régional de Brière. Du point de vue méthodologique, un réseau de photomètres permettra le suivi en temps réel de la pression lumineuse et sa mise en lien avec les paramètres météorologiques. Le couplage de ces données avec (i) les connaissances spatio-temporellespréexistantes sur les enjeux écologiques transitoires propres au territoire et (ii) les connaissances socio-spatiales quant à l’acceptation de mesures de réduction de la pression lumineuse permettra la définition interdisciplinaire de règles d’alerte sur les “moments et zones à enjeux lumière artificielle”. Enfin, la production d’un dashboard permettra de relayer ces alertes auprès du PNR de Brière — partenaire de ce projet — et des maires, décisionnaires finaux en matière de gestion de l’éclairage public