Ranging behaviour of hen harriers breeding in Special Protection Areas in Scotland

Capsule: Breeding female Hen Harriers hunted mostly within 1 km from the nest and males mostly within 2 km. Aims: To quantify temporal and spatial variation in home-range sizes and hunting distances of breeding male and female Hen Harriers. Methods: We radio-tracked ten breeding harriers (five males and five females) in three Special Protection Areas in Scotland between 2002 and 2004. Results: Male Hen Harriers travelled up to 9 km from nests but had a home-range size that averaged only 8 km2 (90% kernel); average home-range size for females was 4.5 km2. Hunting distances did not vary throughout the season. No significant differences were found among study areas, but there was large individual variability. Conclusion: Our results provide information on foraging harriers to support management: actions within 1 km of nesting sites will favour both sexes, and within 2 km will mostly favour males. Our data also suggest overlap between foraging areas of neighbouring birds. Thus, there is the potential for good foraging areas to be utilized by multiple breeding pairs

Methods to quantify avian airspace use in relation to wind energy development

It is likely that there will continue to be a substantial increase in the number of wind turbines as we aim to meet global energy demands through renewable sources. However, these structures can have adverse impacts on airborne wildlife, such as posing a potential collision risk with the turbine structure. A range of methods and technologies have been applied to the collection of bird flight parameters, such as height and speed, to improve the estimation of potential collision compared with traditional visual methods, but these are currently not applied in a consistent and systematic way. To this end, a systematic literature search was conducted to (1) examine the methods and technologies that can be used to provide bird flight data to assess the impact of wind energy developments and (2) provide an updated framework to guide how they might be most usefully applied within the impact assessment process. Four empirical measurement methods were found that improve the estimation of bird flight parameters: radar, telemetry, ornithodolite and LiDAR. These empirical sensor-based tools were typically more often applied in academic peer-reviewed papers than in report-based environmental statements. Where sensor-based tools have been used in the report-based literature, their inconsistent application has resulted in an uncertain regulatory environment for practitioners. Our framework directly incorporates sensor-based methods, together with their limitations and data requirements, from pre-deployment of infrastructure to post-consent monitoring of impacts. This revised approach will help improve the accuracy of estimation of bird flight parameters for ornithological assessment of wind energy. Sensor-based tools may not be the most cost-effective. However, a precedent has been set for wind energy development consent refusal based on ornithological impact assessment, and therefore the cost of collecting accurate and reliable flight data may be balanced favourably against the cost of development consent refusalacceptedVersio

A review to inform the assessment of the risk of collision and displacement in petrels and shearwaters from offshore wind developments in Scotland

The report presents a review of the published literature to collate and synthesise the existing evidence base for the assessment of the impacts of offshore wind farms and associated activities on three focal species: Manx Shearwater, European Storm-petrel and Leach's Storm-petrel. It identifies critical gaps in existing knowledge, outlines the challenges to filling data gaps, and makes recommendations for possible approaches for improving the existing evidence base. The report includes particular reference to Scotland's Sectoral Marine Plan Options, the specific risks posed to nocturnally active petrels and shearwaters by artificial lighting, and how light attraction may influence assessment of other risks (e.g. collision). Potential mitigation methods are outlined

Resolving issues with environmental impact assessment of marine renewable energy installations

Growing concerns about climate change and energy security have fueled a rapid increase in the development of marine renewable energy installations (MREIs). The potential ecological consequences of increased use of these devices emphasizes the need for high quality environmental impact assessment (EIA). We demonstrate that these processes are hampered severely, primarily because ambiguities in the legislation and lack of clear implementation guidance are such that they do not ensure robust assessment of the significance of impacts and cumulative effects. We highlight why the regulatory framework leads to conceptual ambiguities and propose changes which, for the most part, do not require major adjustments to standard practice. We emphasize the importance of determining the degree of confidence in impacts to permit the likelihood as well as magnitude of impacts to be quantified and propose ways in which assessment of population-level impacts could be incorporated into the EIA process. Overall, however, we argue that, instead of trying to ascertain which particular developments are responsible for tipping an already heavily degraded marine environment into an undesirable state, emphasis should be placed on better strategic assessment.Publisher PDFPeer reviewe

Ranging behaviour of Hen Harriers breeding in special protection areas in Scotland

[Capsule]: Breeding female Hen Harriers hunted mostly within 1km from the nest and males mostly within 2 km. [Aims]: To quantify temporal and spatial variation in home-range sizes and hunting distances of breeding male and female Hen Harriers. [Methods]: We radio-tracked ten breeding harriers (five males and five females) in three Special Protection Areas in Scotland between 2002 and 2004. [Results]: Male Hen Harriers travelled up to 9km from nests but had a home-range size that averaged only 8 km2 (90% kernel); average home-range size for females was 4.5km2. Hunting distances did not vary throughout the season. No significant differences were found among study areas, but there was large individual variability. [Conclusion]: Our results provide information on foraging harriers to support management: actions within 1km of nesting sites will favour both sexes, and within 2km will mostly favour males. Our data also suggest overlap between foraging areas of neighbouring birds. Thus, there is the potential for good foraging areas to be utilized by multiple breeding pairs.This work was a partnership project between Royal Society for the Protection of Birds, Scottish National Heritage, Game Conservancy Trust and Centre for Ecology and Hydrology.Peer Reviewe

Integrated modelling of seabird-habitat associations from multi-platform data: a review

Quantifying current and future overlap between human activities and wildlife is a core and growing aim of ecological study, spurring ever more spatial data collection and diversification of observation techniques (surveys, telemetry, citizen science etc.). To meet this aim, data collected via multiple platforms, across different geographical and temporal regions, may need to be integrated, yet many ecologists remain unclear about the relationships between data types and therefore how they can be combined. In seabird research, these applied questions can be particularly pressing because many human activities (e.g. tidal and wind renewables, fishing, shipping, etc.) are concentrated in coastal waters, where many seabirds also aggregate, especially while breeding. In addition, seabird coloniality and density dependence present unique analytical challenges. We review the relevant literature on data integration and illustrate it with example models and data (in an accompanying R-library and vignette (J Matthiopoulos et al., 2022)), to derive methodological and quantitative guidelines for best practice in conducting joint inference for multi-platform data. We use systematic survey data to motivate the key arguments, but also overview developments in integration with other data (e.g., telemetry tracking, citizen science, mark-recapture). We make recommendations on (1) the use of response and explanatory data, (2) the treatment of survey design and observation errors, (3) exploiting dependencies across space and time, (4) accounting for biological phenomena, such as commuting costs from the colony (i.e., accessibility) and density dependence, and (5) the choice of statistical framework. Synthesis and application: Integrated analysis of multi-platform data turns many of the seabird-specific challenges into opportunities for inferring habitat associations and predicting future distributions. Our review proposes practical recommendations for data collection and analysis that will allow seabird conservation to derive maximal benefits from these opportunities