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Review of data used to calculate avoidance rates for collision risk modelling of seabirds 2023


The use of wind energy will be vital to reduce CO2 emissions and achieve UK government targets. However, the use of wind farms can have negative ecological impacts, such as the direct mortality of birds and bats, that need to be assessed (Barthelmie & Pryor 2021). Direct mortality of seabirds is especially pertinent due to the increase in offshore wind farms (Higgins & Foley 2014) and the need to ensure the long-term viability of seabird populations whilst switching to renewable energy sources.

Collision risk modelling is an integral tool used to assess the impact of wind farms on seabird populations (Masden & Cook 2016). These models are sensitive to some key parameters including flight heights, flight speeds, bird densities and the avoidance rate (Black et al. 2019). The avoidance rate is typically thought of as quantifying active avoidance behaviour in response to wind farms. There is therefore a need to ensure that the avoidance rate is as accurate as possible and that it reflects the true behaviour of seabirds.

The purpose of this report was to conduct a review of the avoidance rates recommended in Cook (2021). The instigation for this review was a jackknife analysis, carried out by MacArthur Green (Trinder 2021), which found a single site (Kleine Pathoweg) was highly influential on the avoidance rates recommended by Cook (2021). Each data-set used by Cook (2021) was reviewed and the suitability of each data-set for calculation of avoidance rates was assessed.

Accompanying the report are three annexes (annexes 1, 2 and 3).

  • Annex 1: Changes made to dataset in Cook (2021) (spreadsheet)
  • Annex 2: Ozsanlav-Harris et al. (2022) Collision Data (csv file)
  • Annex 3: Ozsanlav-Harris et al. (2022) markdown code (Rmd file)

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Resource type Publication

Topic category Environment

Reference date 2023·03·01

Ozsanlav-Harris, L., Inger, R. & Sherley, R. 2023. Review of data used to calculate avoidance rates for collision risk modelling of seabirds. JNCC Report 732, JNCC, Peterborough, ISSN 0963-8091.

This report was produced for JNCC under an external contract by University of Exeter, for/under the Framework Agreement F21-0708-1581(14).

Responsible organisation
Communications, JNCC publisher

Limitations on public access No limitations

Use constraints Available under the Open Government Licence 3.0

Metadata date 2023·03·30

Metadata point of contact
Communications, JNCC

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