Scottish Marine and Freshwater Science Volume 5 Number 13: Population consequences of displacement from proposed offshore wind energy developments for seabirds breeding at Scottish SPAs

Report on a project which aimed to develop a model to estimate the population consequences of displacement from proposed offshore wind energy developments for key species of seabirds breeding at SPAs in proximity to proposed Forth/Tay offshore wind farm d


Appendix F. Full model results from exploratory runs with 1000 birds

Mean results are presented in the following pages. Because of the large sizes of tables, uncertainty results (see below for description) are available as Excel spreadsheets.

F.1. Prey availability in good, moderate and poor years

All estimated parameters in the model (not directly derived from data) were fitted assuming moderate prey availability. No direct data were available on prey availability, so we considered situations in which parameters in the birds estimated by the model that are sensitive to prey availability (adult mass change, chick mass growth, chick survival, adult foraging time, adult flight time) showed values that matched moderate values in the empirical data pertained to a moderate year. Similarly, to assess the impact of wind farms in poor and good years, prey availability was altered until model output matched empirical changes in adult body mass and chick survival observed during 'poor' and 'good' years (Table F. 1)

Table F. 1. Observed changes to adult mass and population productivity in good, moderate and poor prey years for all species. These values were used to alter prey levels in good and poor scenarios such that model output matched as closely to observed values as possible. Sources. Freeman, S., Searle, K. Bogdanova, M., Wanless, S. & Daunt, F. (2013) Population dynamics of Forth & Tay breeding seabirds: review of available models and modelling of key breeding populations. Ref MSQ-0006. Draft final report to Marine Scotland Science; Gaston, A.J. & Hipfner, J.M. (2006) Body mass changes in Brunnich's guillemots Uria lomvia with age and breeding stage. Journal of Avian Biology 37: 101-109; Harris MP, Wanless S (1988) Measurement and seasonal changes in weight of guillemots Uria aalge at a breeding colony. Ring and Migr 9: 32-36; Jarvis, M. (1971) Ethology and ecology of the South African Gannet Sula capensis, Unpublished PhD thesis, University of Cape Town; Harris, M.P. (1979) Measurements and weights of British puffins. Bird Study 26: 179-186; Nelson, B. (2013) Early warnings of climate change on ecosystems: hormonally-mediated life-history decisions in seabirds. Unpublished PhD thesis, University of Glasgow; Newell, M., Harris, M., Wanless, S., Burthe, S., Bogdanova, M., Gunn, C., Daunt, F. (2012) The Isle of May Long-Term Study ( IMLOTS) Seabird Annual Breeding Success 1982-2012. NERC-Environmental Information Data Centre. doi: 10.5285/d38b609b-7bc1-4204-86dd-022375208d4f; CEH unpublished data; Seabird Monitoring Programme online database ( http://jncc.defra.gov.uk/smp/)

Kw good moderate poor
mass change start vs end 0% 10% 20%
productivity 100% 50% 10%
Gu good moderate poor
mass change start vs end 0% 7% 14%
productivity 90% 85% 40%
Rz good moderate poor
mass change start vs end 0% 7% 14%
productivity 85% 80% 50%
Pu good moderate poor
mass change start vs end 0% 7% 14%
productivity 95% 85% 75%
Ga good moderate poor
mass change start vs end 0.0% 2.5% 5.0%
productivity 80% 75% 70%

F.2. Black-legged kittiwake Rissa tridactyla

Four SPAs are designated for this species in the region (Buchan Ness to Collieston Coast, Fowlsheugh, Forth Islands and St Abb's Head to Fastcastle). For each SPA, and all SPAs combined, we carried out three sets of scenarios, presented in sections F.2.1, F.2.2 and F.2.3.

F.2.1. The effects of wind farms and prey availability

The following scenarios were explored:

  • Effect of wind farm:
    • No wind farms (the baseline scenario)
    • each of the four individual wind farms separately
    • the combined impact of all four wind farms
  • Overall prey availability
    • Good
    • Moderate
    • Poor

The above scenarios resulted in a total of 18 scenarios (six wind farms scenarios in three prey availabilities). For all scenarios, we assumed a 1km exclusion buffer, and that 100% of birds that were intending to forage in the wind farm were displaced and for 100% of birds that were intending to forage beyond the wind farm, it acted as a barrier such that they flew around it, not through it.

Figure F. 1a shows the distribution of birds from all SPAs in the baseline scenario and Figure F. 1b the distribution of birds from all SPAs in the scenario with all four wind farms under moderate prey availability and homogeneous prey distribution. These two scenarios are shown again in Figure F. 2a and Figure F. 2b based on heterogeneous prey.

The number of birds displaced and for whom the wind farm(s) acted as a barrier is shown for all 18 scenarios in Table F. 2 under homogeneous prey distribution and Table F. 3 with heterogeneous prey.

Mean adult body mass is presented as a histogram plot showing the difference between the baseline and the four wind farm scenario for all SPAs combined under moderate prey availability with homogeneous Figure F. 3 and heterogeneous prey Figure F. 4. Mean adult mass at the end of the breeding season is given for all 18 scenarios is given in Table F. 4 (homogeneous prey) and Table F. 5 (heterogeneous prey). Adult survival change relative to the baseline can be found in Table F. 6 (homogeneous prey) and Table F. 7 (heterogeneous prey). Finally, chick survival change relative to the baseline can be found in Table F. 8 (homogeneous prey) and Table F. 9 (heterogeneous prey).

Figure F. 1: Kittiwake. Distribution of birds from each SPA a) in the absence of wind farms and b) with all four wind farms present, under moderate prey availability and homogeneous prey distribution.

Figure F. 1

Figure F. 2. Kittiwake. Distribution of birds from each SPA a) in the absence of wind farms and b) with all four wind farms present, under moderate prey availability and heterogeneous prey distribution.

Figure F. 2

Table F. 2 Kittiwake. Mean across time steps percentage of the population displaced and for whom the wind farm(s) were a barrier for each wind farm scenario under three prey availabilities for each SPA and all four SPAs combined, based on homogeneous prey distribution.

Prey SPA Baseline NnG Inch Alpha Bravo All 4
Disp Barr Disp Barr Disp Barr Disp Barr Disp Barr Disp Barr
good All 0.0 0.0 0.7 4.3 0.4 1.1 1.2 1.9 1.2 1.6 3.3 4.1
good Buchan Ness 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0
good Fowlsheugh 0.0 0.0 0.0 0.0 0.3 0.3 2.7 4.5 2.1 3.2 4.8 2.9
good Forth 0.0 0.0 3.9 31.8 2.6 7.1 1.9 3.2 2.6 3.2 11.7 22.7
good St Abbs 0.0 0.0 1.1 2.3 0.6 0.6 0.6 0.6 1.1 1.7 2.9 1.7
moderate All 0.0 0.0 0.7 4.3 0.4 1.1 1.2 1.9 1.2 1.6 3.4 4.1
moderate Buchan Ness 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0
moderate Fowlsheugh 0.0 0.0 0.0 0.0 0.3 0.3 2.7 4.5 2.4 3.2 4.8 3.2
moderate Forth 0.0 0.0 4.5 31.8 2.6 7.8 1.9 3.2 3.2 3.2 11.7 22.1
moderate St Abbs 0.0 0.0 1.1 1.7 0.0 0.6 0.6 0.6 1.1 1.1 2.9 1.7
poor All 0.0 0.0 0.7 4.3 0.5 1.0 1.2 1.9 1.2 1.7 3.4 4.0
poor Buchan Ness 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0
poor Fowlsheugh 0.0 0.0 0.0 0.0 0.3 0.3 2.7 4.8 2.1 3.2 4.8 2.9
poor Forth 0.0 0.0 4.5 31.2 2.6 7.1 1.9 3.2 2.6 3.2 11.7 22.1
poor St Abbs 0.0 0.0 0.6 2.3 0.6 0.6 0.6 0.6 1.1 1.1 2.9 1.7

Table F. 3 Kittiwake. Mean across time steps percentage of the population displaced and for whom the wind farm(s) were a barrier for each wind farm scenario under three prey availabilities for each SPA and all four SPAs combined, based on heterogeneous prey distribution.

Prey SPA Baseline NnG Inch Alpha Bravo All 4
Disp Barr Disp Barr Disp Barr Disp Barr Disp Barr Disp Barr
good All 0.0 0.0 0.7 4.3 0.5 1.1 1.2 2.0 1.2 1.7 3.4 4.1
good Buchan Ness 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0
good Fowlsheugh 0.0 0.0 0.0 0.0 0.3 0.3 2.7 4.8 2.1 3.5 5.1 2.9
good Forth 0.0 0.0 3.9 31.8 2.6 7.1 1.9 3.2 3.2 3.2 11.0 22.1
good St Abbs 0.0 0.0 1.1 2.3 0.0 0.6 0.6 0.6 1.1 1.7 2.9 1.7
moderate All 0.0 0.0 0.7 4.2 0.4 1.1 1.2 1.9 1.2 1.6 3.4 4.1
moderate Buchan Ness 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0
moderate Fowlsheugh 0.0 0.0 0.0 0.0 0.3 0.3 2.7 4.5 2.1 2.9 5.1 2.9
moderate Forth 0.0 0.0 3.9 31.2 2.6 7.8 1.9 3.2 2.6 3.2 11.0 22.7
moderate St Abbs 0.0 0.0 1.1 1.7 0.0 0.6 0.6 0.6 1.1 1.7 2.9 1.7
poor All 0.0 0.0 0.7 4.3 0.4 1.1 1.2 1.9 1.2 1.6 3.4 4.1
poor Buchan Ness 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0
poor Fowlsheugh 0.0 0.0 0.0 0.0 0.3 0.3 2.7 4.8 2.1 3.2 5.1 2.9
poor Forth 0.0 0.0 4.5 31.2 2.6 7.1 1.9 3.2 2.6 3.2 11.7 22.7
poor St Abbs 0.0 0.0 0.6 2.3 0.6 0.6 0.6 0.6 1.1 1.7 2.9 1.7

Figure F. 3 Kittiwake. Histogram of distribution of adult body mass at all four SPAs at the end of the chick-rearing period under moderate conditions with homogeneous prey distribution, with purple bars denoting the distribution of masses shared between baseline scenario and scenario with all four wind farms, blue denoting the distribution in the scenario with all four wind farms not the baseline, and pink denoting the distribution in the baseline and not the scenario with all four wind farms.

Figure F. 3

Figure F. 4. Kittiwake. Histogram of distribution of adult body mass at all four SPAs at the end of the chick-rearing period under moderate conditions with heterogeneous prey distribution, with purple bars denoting the distribution of masses shared between baseline scenario and scenario with all four wind farms, blue denoting the distribution in the scenario with all four wind farms not the baseline, and pink denoting the distribution in the baseline and not the scenario with all four wind farms.

Figure F. 4

Table F. 4. Kittiwake. Mean adult body mass at the end of chick-rearing in the baseline and each wind farm scenario for each SPA and all combined for each prey availability, based on homogeneous prey distribution.

Prey SPA Baseline NnG Inch Alpha Bravo All 4
good All 354.4 353.8 354.3 353.5 353.5 352.7
good Buchan Ness 354.4 354.3 354.3 353.9 354.2 354.1
good Fowlsheugh 352.2 351.6 352.2 350.9 350.6 349.8
good Forth 354.9 351.8 353.8 352.9 353.0 349.7
good St Abbs 358.5 358.8 359.0 358.7 358.2 357.6
moderate All 338.3 337.5 337.7 337.5 337.1 335.8
moderate Buchan Ness 336.7 336.7 336.1 336.5 336.0 336.8
moderate Fowlsheugh 334.8 336.3 334.7 333.6 334.2 332.9
moderate Forth 343.8 333.2 339.9 340.1 338.3 331.2
moderate St Abbs 346.1 346.0 346.5 346.5 345.5 343.5
poor All 316.7 314.8 316.2 315.3 315.1 314.3
poor Buchan Ness 313.0 313.0 313.0 313.8 313.7 313.9
poor Fowlsheugh 312.8 313.1 313.4 310.1 310.6 310.9
poor Forth 324.6 311.7 321.0 320.1 318.9 309.2
poor St Abbs 328.4 326.1 327.2 326.6 325.9 327.0

Table F. 5. Kittiwake. Mean adult body mass at the end of chick-rearing in the baseline and each wind farm scenario for each SPA and all combined for each prey availability, based on heterogeneous prey distribution.

Prey SPA Baseline NnG Inch Alpha Bravo All 4
good All 353.1 352.3 352.9 352.2 352.5 351.3
good Buchan Ness 353.3 353.1 353.4 353.1 353.5 353.1
good Fowlsheugh 351.5 351.0 350.9 349.8 349.9 348.9
good Forth 352.0 348.2 351.0 350.2 350.4 346.1
good St Abbs 357.0 356.6 357.2 356.9 356.8 355.7
moderate All 334.9 333.8 334.5 333.7 333.7 331.9
moderate Buchan Ness 335.0 336.1 335.4 335.1 335.4 335.5
moderate Fowlsheugh 331.1 331.5 330.9 328.4 329.5 328.1
moderate Forth 337.1 326.0 334.1 335.6 332.2 322.8
moderate St Abbs 341.0 339.3 340.3 339.4 338.8 337.8
poor All 318.7 317.6 317.9 317.9 317.5 315.5
poor Buchan Ness 317.3 318.7 316.9 318.8 318.2 317.6
poor Fowlsheugh 314.5 315.7 315.1 311.4 312.7 312.2
poor Forth 323.3 309.4 318.4 320.8 317.9 307.9
poor St Abbs 328.0 325.6 326.4 326.7 325.3 323.4

Table F. 6. Kittiwake. Mean change in adult survival (as a percentage point) between each wind farm scenario and the baseline for each SPA and all combined, and for each prey availability, based on homogeneous prey distribution.

Prey SPA NnG Inch Alpha Bravo All 4
good All -0.2 0.0 -0.4 -0.4 -0.7
good Buchan Ness -0.1 0.0 -0.2 -0.1 -0.1
good Fowlsheugh -0.2 0.1 -0.5 -0.7 -0.9
good Forth -1.3 -0.5 -0.9 -0.8 -2.3
good St Abbs 0.1 0.2 0.1 -0.2 -0.4
moderate All -0.6 -0.5 -0.5 -0.8 -1.7
moderate Buchan Ness -0.1 -0.3 -0.1 -0.5 0.1
moderate Fowlsheugh 0.8 -0.3 -0.9 -0.5 -1.4
moderate Forth -7.5 -2.6 -2.4 -3.7 -9.1
moderate St Abbs 0.0 0.3 0.3 -0.4 -1.8
poor All -1.5 -0.4 -1.1 -1.2 -2.0
poor Buchan Ness 0.0 0.1 0.7 0.5 0.7
poor Fowlsheugh 0.2 0.3 -2.3 -1.9 -1.7
poor Forth -10.4 -3.0 -3.7 -4.6 -12.5
poor St Abbs -1.8 -1.1 -1.4 -2.1 -1.2

Table F. 7. Kittiwake. Mean change in adult survival (as a percentage point) between each wind farm scenario and the baseline for each SPA and all combined, and for each prey availability, based on heterogeneous prey distribution.

Prey SPA NnG Inch Alpha Bravo All 4
good All -0.3 -0.1 -0.4 -0.3 -0.8
good Buchan Ness 0.0 0.1 -0.1 0.1 -0.1
good Fowlsheugh -0.3 -0.2 -0.8 -0.7 -1.1
good Forth -1.7 -0.5 -0.8 -0.7 -2.7
good St Abbs -0.1 0.1 0.0 -0.1 -0.5
moderate All -0.7 -0.2 -0.8 -0.8 -2.1
moderate Buchan Ness 0.7 0.3 0.1 0.3 0.4
moderate Fowlsheugh 0.3 -0.1 -1.8 -1.1 -2.1
moderate Forth -7.8 -2.0 -1.2 -3.4 -10.3
moderate St Abbs -1.1 -0.6 -1.2 -1.5 -2.2
poor All -1.0 -0.7 -0.7 -1.0 -2.7
poor Buchan Ness 1.0 -0.3 1.1 0.7 0.2
poor Fowlsheugh 0.8 0.4 -2.5 -1.6 -2.1
poor Forth -11.4 -4.2 -2.2 -4.4 -12.4
poor St Abbs -2.0 -1.3 -1.1 -2.2 -3.8

Table F. 8. Kittiwake. Mean change in chick survival (as a percentage point) between each wind farm scenario and the baseline for each SPA and all combined, and for each prey availability, based on homogeneous prey distribution.

Prey SPA NnG Inch Alpha Bravo All 4
good All -2.0 -1.8 -1.4 -1.9 -3.6
good Buchan Ness -2.6 -1.9 -1.1 -2.1 -2.6
good Fowlsheugh -0.9 -1.1 -1.6 -2.1 -3.5
good Forth -2.3 -2.3 -1.6 -1.8 -5.5
good St Abbs -2.3 -2.3 -1.6 -1.2 -4.8
moderate All -3.3 -2.7 -0.9 -5.3 -6.3
moderate Buchan Ness -0.6 -1.3 0.1 -1.2 -1.8
moderate Fowlsheugh -1.6 -0.1 -2.1 -6.4 -4.9
moderate Forth -15.6 -8.1 -3.6 -14.0 -19.7
moderate St Abbs -3.5 -7.4 1.2 -7.1 -10.3
poor All -2.3 -0.9 -1.5 -0.8 -3.1
poor Buchan Ness -0.3 -0.1 -0.6 -0.5 -1.8
poor Fowlsheugh -1.5 -0.2 -1.7 -0.6 -2.2
poor Forth -9.9 -3.9 -3.1 -1.0 -8.1
poor St Abbs -3.0 -2.1 -2.5 -1.8 -4.4

Table F. 9. Kittiwake. Mean change in chick survival (as a percentage point) between each wind farm scenario and the baseline for each SPA and all combined, and for each prey availability, based on heterogeneous prey distribution.

Prey SPA NnG Inch Alpha Bravo All 4
good All -0.1 0.0 0.4 -1.9 -2.0
good Buchan Ness 0.6 -0.2 0.3 -1.7 -2.0
good Fowlsheugh 1.0 1.1 0.9 -2.5 -1.6
good Forth -2.9 0.5 0.3 -2.3 -1.6
good St Abbs -2.1 -2.1 -0.2 -0.9 -3.5
moderate All -3.8 0.2 -2.0 -1.8 -7.1
moderate Buchan Ness -3.6 2.9 1.0 0.8 -2.9
moderate Fowlsheugh -2.7 -1.9 -6.1 -4.4 -9.9
moderate Forth -10.7 -2.1 -3.6 -3.6 -15.8
moderate St Abbs -0.7 -0.9 0.0 -1.8 -5.5
poor All -3.2 -1.9 -2.1 -2.2 -4.0
poor Buchan Ness 0.6 -0.3 1.4 1.7 -0.9
poor Fowlsheugh -2.0 -0.7 -3.8 -3.5 -3.1
poor Forth -13.5 -7.5 -9.6 -5.2 -14.0
poor St Abbs -7.6 -3.7 -1.8 -7.8 -5.8

F.2.2. The effects of buffer width

The following scenarios were explored:

  • 0km buffer around wind farm
  • 0.5km buffer around wind farm
  • 1km buffer around wind farm

The three scenarios were carried out on all SPAs in three prey availability levels for Neart na Gaoithe wind farm only. The third scenario is a repeat scenario from section F.2.1. For all scenarios, we assumed that 100% of birds that were intending to forage in the wind farm were displaced and for 100% of birds that were intending to forage beyond the wind farm, it acted as a barrier such that they flew around it, not through it.

Adult survival change relative to the baseline can be found in Table F. 10 and Table F. 11 for homogeneous and GPS-derived prey, respectively. Chick survival change relative to the baseline can be found in Table F. 12 and Table F 13 or homogeneous and GPS-derived prey, respectively.

Table F. 10. Kittiwake. Mean change in adult survival (as a percentage point) between Neart na Gaoithe scenario and the baseline at three alternative buffer widths, for each SPA and all combined, and for each prey availability, based on homogeneous prey distribution.

Prey SPA Buffer width
0 km 0.5 km 1 km
good All -0.2 -0.2 -0.2
good Buchan Ness 0.0 0.1 -0.1
good Fowlsheugh -0.2 -0.2 -0.2
good Forth -1.3 -1.5 -1.3
good St Abbs 0.1 0.1 0.1
moderate All -0.7 -0.8 -0.6
moderate Buchan Ness -0.5 -0.1 -0.1
moderate Fowlsheugh 0.5 0.2 0.8
moderate Forth -5.9 -7.4 -7.5
moderate St Abbs 0.5 0.7 0.0
poor All -1.2 -1.7 -1.5
poor Buchan Ness 0.5 0.0 0.0
poor Fowlsheugh 0.3 -0.6 0.2
poor Forth -10.1 -10.4 -10.4
poor St Abbs -1.4 -1.4 -1.8

Table F. 11. Kittiwake. Mean change in adult survival (as a percentage point) between Neart na Gaoithe scenario and the baseline at three alternative buffer widths, for each SPA and all combined, and for each prey availability, based on heterogeneous prey distribution.

Prey SPA Buffer width
0 km 0.5 km 1 km
good All -0.2 -0.3 -0.3
good Buchan Ness 0.2 0.0 0.0
good Fowlsheugh 0.0 0.0 -0.3
good Forth -1.7 -1.5 -1.7
good St Abbs -0.1 -0.4 -0.1
moderate All -0.6 -0.7 -0.7
moderate Buchan Ness 0.5 0.9 0.7
moderate Fowlsheugh -0.1 -0.2 0.3
moderate Forth -6.8 -7.6 -7.8
moderate St Abbs 0.3 -0.4 -1.1
poor All -1.1 -1.2 -1.0
poor Buchan Ness 0.6 0.6 1.0
poor Fowlsheugh 0.3 -0.2 0.8
poor Forth -9.5 -10.2 -11.4
poor St Abbs -1.6 -0.9 -2.0

Table F. 12 Kittiwake. Mean change in chick survival (as a percentage point) between Neart na Gaoithe scenario and the baseline at three alternative buffer widths, for each SPA and all combined, and for each prey availability, based on homogeneous prey distribution.

Prey SPA Buffer width
0 km 0.5 km 1 km
good All -2.2 -1.8 -2.0
good Buchan Ness -3.1 -2.3 -2.6
good Fowlsheugh -0.7 -1.2 -0.9
good Forth -2.6 -1.8 -2.3
good St Abbs -2.1 -1.8 -2.3
moderate All 0.6 -3.2 -3.3
moderate Buchan Ness 2.6 -1.6 -0.6
moderate Fowlsheugh 3.0 -1.8 -1.6
moderate Forth -10.7 -14.6 -15.6
moderate St Abbs -0.2 -0.5 -3.5
poor All -2.0 -1.4 -2.3
poor Buchan Ness -0.9 -0.2 -0.3
poor Fowlsheugh -1.0 -0.6 -1.5
poor Forth -9.4 -8.1 -9.9
poor St Abbs -0.7 -0.2 -3.0

Table F. 13. Kittiwake. Mean change in chick survival (as a percentage point) between Neart na Gaoithe scenario and the baseline at three alternative buffer widths, for each SPA and all combined, and for each prey availability, based on heterogeneous prey distribution.

Prey SPA Buffer width
0 km 0.5 km 1 km
good All -0.1 -0.4 -0.1
good Buchan Ness -0.2 -0.4 0.6
good Fowlsheugh 1.5 0.2 1.0
good Forth -3.4 -2.1 -2.9
good St Abbs 0.0 0.0 -2.1
moderate All -3.5 -4.5 -3.8
moderate Buchan Ness -0.6 -1.9 -3.6
moderate Fowlsheugh -6.1 -4.3 -2.7
moderate Forth -11.7 -14.0 -10.7
moderate St Abbs 0.7 -3.9 -0.7
poor All -3.1 -3.2 -3.2
poor Buchan Ness -0.2 -0.1 0.6
poor Fowlsheugh -1.9 -3.8 -2.0
poor Forth -14.3 -13.3 -13.5
poor St Abbs -4.1 -1.6 -7.6

F.2.3. The effects of percentage of birds displaced

The following scenarios were explored:

  • 50% of birds displaced and 50% for whom the wind farm acted as a barrier
  • 0% of birds displaced and 100% for whom the wind farm acted as a barrier
  • 100% of birds displaced and 0% for whom the wind farm acted as a barrier

The three scenarios were carried out on all SPAs in three prey availability levels for all wind farms combined. The results were compared with equivalent scenarios where level for displacement and barrier effect were both 100% (repeat of scenario presented in Section F.2.1). For all scenarios, we assumed a buffer with of 1km.

Adult survival change relative to the baseline can be found Table F. 14 and Table F. 15 for homogeneous and GPS-derived prey, respectively. Chick survival change relative to the baseline can be found in Table F. 16 and Table F. 17 for homogeneous and GPS-derived prey, respectively.

Table F. 14. Kittiwake. Mean change in adult survival (as a percentage point) between scenario of all four wind farms combined and the baseline in relation to alternative displacement and barrier percentages, for each SPA and all combined, and for each prey availability, based on homogeneous prey distribution.

Prey SPA Displacement/Barrier %
100/100 50/50 0/100 100/0
good All -0.7 -0.3 -0.3 -0.3
good Buchan Ness -0.1 -0.1 0.0 0.0
good Fowlsheugh -0.9 -0.3 -0.4 -0.4
good Forth -2.3 -1.1 -1.5 -0.7
good St Abbs -0.4 -0.1 0.2 -0.5
moderate All -1.7 -0.7 -1.3 -1.0
moderate Buchan Ness 0.1 0.0 -0.3 -0.5
moderate Fowlsheugh -1.4 -0.5 -1.2 -1.0
moderate Forth -9.1 -3.6 -6.9 -3.0
moderate St Abbs -1.8 -0.6 -0.1 -0.9
poor All -2.0 -1.0 -1.6 -1.0
poor Buchan Ness 0.7 0.0 -0.1 0.1
poor Fowlsheugh -1.7 -0.3 -0.4 -1.2
poor Forth -12.5 -5.6 -10.5 -3.6
poor St Abbs -1.2 -1.6 -1.4 -1.3

Table F. 15. Kittiwake. Mean change in adult survival (as a percentage point) between of all four wind farms combined and the baseline in relation to alternative displacement and barrier percentages, for each SPA and all combined, and for each prey availability, based on heterogeneous prey distribution.

Prey SPA Displacement/Barrier %
100/100 50/50 0/100 100/0
good All -0.8 -0.3 -0.5 -0.4
good Buchan Ness -0.1 0.1 -0.2 -0.1
good Fowlsheugh -1.1 -0.5 -0.5 -0.5
good Forth -2.7 -1.4 -1.6 -1.2
good St Abbs -0.5 -0.2 -0.1 -0.4
moderate All -2.1 -0.8 -1.1 -0.5
moderate Buchan Ness 0.4 0.2 0.8 0.5
moderate Fowlsheugh -2.1 -0.5 -1.1 -0.9
moderate Forth -10.3 -4.3 -7.0 -2.9
moderate St Abbs -2.2 -1.0 -1.8 -0.8
poor All -2.7 -0.8 -1.7 -1.1
poor Buchan Ness 0.2 0.9 0.6 0.2
poor Fowlsheugh -2.1 -0.3 -1.0 -1.1
poor Forth -12.4 -5.9 -9.7 -4.3
poor St Abbs -3.8 -2.1 -2.8 -2.2

Table F. 16. Kittiwake. Mean change in chick survival (as a percentage point) between of all four wind farms combined and the baseline in relation to alternative displacement and barrier percentages, for each SPA and all combined, and for each prey availability, based on homogeneous prey distribution.

Prey SPA Displacement/Barrier %
100/100 50/50 0/100 100/0
good All -3.6 -1.6 -2.0 -1.8
good Buchan Ness -2.6 -1.7 -1.7 -1.5
good Fowlsheugh -3.5 -2.0 -1.5 -1.5
good Forth -5.5 -1.0 -3.1 -3.1
good St Abbs -4.8 -1.2 -2.8 -2.1
moderate All -6.3 -3.3 -4.4 -1.3
moderate Buchan Ness -1.8 -2.5 -0.4 0.0
moderate Fowlsheugh -4.9 -1.4 -4.4 -2.3
moderate Forth -19.7 -12.0 -14.3 -1.6
moderate St Abbs -10.3 -2.1 -7.1 -2.8
poor All -3.1 -2.0 -2.0 -2.1
poor Buchan Ness -1.8 -0.5 -0.9 -0.9
poor Fowlsheugh -2.2 -1.3 -1.5 -2.6
poor Forth -8.1 -4.2 -8.3 -2.6
poor St Abbs -4.4 -6.2 -0.5 -4.4

Table F. 17. Kittiwake. Mean change in chick survival (as a percentage point) between of all four wind farms combined and the baseline in relation to alternative displacement and barrier percentages, for each SPA and all combined, and for each prey availability, based on heterogeneous prey distribution.

Prey SPA Displacement/Barrier %
100/100 50/50 0/100 100/0
good All -2.0 -1.3 -1.9 -1.4
good Buchan Ness -2.0 -2.4 -1.4 -1.4
good Fowlsheugh -1.6 1.5 -0.7 -0.9
good Forth -1.6 -1.6 -2.9 -3.1
good St Abbs -3.5 -4.1 -5.1 -1.4
moderate All -7.1 -1.3 -3.2 0.0
moderate Buchan Ness -2.9 0.3 -0.6 2.2
moderate Fowlsheugh -9.9 -4.9 -5.6 -3.5
moderate Forth -15.8 -4.7 -11.7 -1.8
moderate St Abbs -5.5 4.6 2.1 3.0
poor All -4.0 -2.0 -4.2 -2.5
poor Buchan Ness -0.9 0.6 0.1 -0.2
poor Fowlsheugh -3.1 -1.7 -4.3 -2.1
poor Forth -14.0 -10.9 -14.8 -8.6
poor St Abbs -5.8 -2.5 -6.9 -4.6

F.3. Common guillemot Uria aalge

Four SPAs are designated for this species in the region (Buchan Ness to Collieston Coast, Fowlsheugh, Forth Islands and St Abb's Head to Fastcastle). For each SPA, and all SPAs combined, we carried out three sets of scenarios, presented in sections F.3.1, F.3.2 and F.3.3. Models based on heterogeneous prey included birds from all SPAs, but outputs were only recorded for Fowlsheugh, Forth Islands and St Abb's Head to Fastcastle, because of the lack of sufficient GPS data available from Buchan Ness to Collieston Coast.

F.3.1. The effects of wind farms and prey availability

The following scenarios were explored:

  • Effect of wind farm:
    • No wind farms (the baseline scenario)
    • each of the four individual wind farms separately
    • the combined impact of all four wind farms
  • Overall prey availability
    • Good
    • Moderate
    • Poor

The above scenarios resulted in a total of 18 scenarios (six wind farms scenarios in three prey availabilities). For all scenarios, we assumed a 1km exclusion buffer, and that 100% of birds that were intending to forage in the wind farm were displaced and for 100% of birds that were intending to forage beyond the wind farm, it acted as a barrier such that they flew around it, not through it.

Figure F. 5a shows the distribution of birds from all SPAs in the baseline scenario and Figure F. 5b the distribution of birds from all SPAs in the scenario with all four wind farms under moderate prey availability and homogeneous prey distribution. These two scenarios are shown again in Figure F. 6a and Figure F. 6b based on heterogeneous prey.

The number of birds displaced and for whom the wind farm(s) acted as a barrier is shown for all 18 scenarios in Table F. 18 under homogeneous prey distribution and Table F. 19 with heterogeneous prey.

Mean adult body mass is presented as a histogram plot showing the difference between the baseline and the four wind farm scenario for all SPAs combined under moderate prey availability with homogeneous Figure F. 7 and heterogeneous prey Figure F. 8. Mean adult mass at the end of the breeding season is given for all 18 scenarios is given in Table F. 20 (homogeneous prey) and Table F.21 (heterogeneous prey). Adult survival change relative to the baseline can be found in Table F. 22 (homogeneous prey) and Table F. 23 (heterogeneous prey). Finally, chick survival change relative to the baseline can be found in Table F. 24 (homogeneous prey) and Table F25.

Figure F. 5. Guillemot. Distribution of birds from each SPA a) in the absence of wind farms and b) with all four wind farms present, under moderate prey availability and homogeneous prey distribution.

Figure F. 5

Figure F. 6. Guillemot. Distribution of birds from each SPA a) in the absence of wind farms and b) with all four wind farms present, under moderate prey availability and prey distribution derived from seabird GPS data.

Figure F. 6

Table F. 18. Guillemot. Mean across time steps percentage of the population displaced and for whom the wind farm(s) were a barrier for each wind farm scenario under three prey availabilities for each SPA and all four SPAs combined, based on homogeneous prey distribution.

Prey SPA Buffer width
0 km 0.5 km 1 km
good All -0.7 -0.9 -1.0
good Fowlsheugh 0.1 0.1 -0.2
good Forth -4.9 -6.3 -6.1
good St Abbs -0.2 -0.1 -0.1
moderate All -0.7 -0.8 -1.1
moderate Fowlsheugh -0.2 -0.4 -0.3
moderate Forth -2.4 -2.3 -3.3
moderate St Abbs 0.2 0.3 0.3
poor All -0.5 -0.7 -0.9
poor Fowlsheugh 0.3 0.6 0.4
poor Forth -3.2 -3.3 -3.8
poor St Abbs 0.9 -0.4 -0.4

Table F. 19. Guillemot. Mean across time steps percentage of the population displaced and for whom the wind farm(s) were a barrier for each wind farm scenario under three prey availabilities for each SPA and all three SPAs combined, based on heterogeneous prey distribution.

Prey SPA Baseline NnG Inch Alpha Bravo All 4
Disp Barr Disp Barr Disp Barr Disp Barr Disp Barr Disp Barr
good All 0.0 0.0 0.6 3.3 0.5 0.1 0.3 0.3 0.1 0.2 1.5 2.3
good Fowlsheugh 0.0 0.0 0.0 0.0 0.3 0.0 0.8 0.8 0.3 0.5 1.3 0.5
good Forth 0.0 0.0 2.6 14.4 1.5 0.5 0.0 0.0 0.0 0.0 4.1 9.3
good St Abbs 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0
moderate All 0.0 0.0 0.6 3.3 0.5 0.1 0.3 0.3 0.1 0.2 1.5 2.2
moderate Fowlsheugh 0.0 0.0 0.0 0.0 0.3 0.0 0.8 0.8 0.3 0.5 1.3 0.5
moderate Forth 0.0 0.0 2.6 14.4 1.5 0.5 0.0 0.0 0.0 0.0 4.1 8.8
moderate St Abbs 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0
poor All 0.0 0.0 0.6 3.3 0.5 0.1 0.3 0.3 0.1 0.2 1.5 2.3
poor Fowlsheugh 0.0 0.0 0.0 0.0 0.3 0.0 0.8 0.8 0.3 0.5 1.3 0.5
poor Forth 0.0 0.0 2.6 14.4 1.5 0.5 0.0 0.0 0.0 0.0 4.1 9.3
poor St Abbs 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0

Figure F. 7. Guillemot. Histogram of distribution of adult body mass at Forth Islands SPA at the end of the chick-rearing period under moderate conditions with homogeneous prey distribution, with purple bars denoting the distribution of masses shared between baseline scenario and scenario with all four wind farms, blue denoting the distribution in the scenario with all four wind farms not the baseline, and pink denoting the distribution in the baseline and not the scenario with all four wind farms.

Figure F. 7

Figure F. 8. Guillemot. Histogram of distribution of adult body mass at Forth Islands SPA at the end of the chick-rearing period under moderate conditions with heterogeneous prey distribution, with purple bars denoting the distribution of masses shared between baseline scenario and scenario with all four wind farms, blue denoting the distribution in the scenario with all four wind farms not the baseline, and pink denoting the distribution in the baseline and not the scenario with all four wind farms.

Figure F. 8

Table F. 20. Guillemot. Mean adult body mass at the end of chick-rearing in the baseline and each wind farm scenario for each SPA and all combined for each prey availability, based on homogeneous prey distribution.

Prey SPA Baseline NnG Inch Alpha Bravo All 4
good All 885.0 883.7 885.2 885.5 885.8 884.2
good Buchan Ness 895.3 894.4 895.2 894.8 894.8 895.2
good Fowlsheugh 881.8 881.6 881.2 881.3 882.2 880.3
good Forth 901.5 893.6 901.3 902.4 902.5 896.2
good St Abbs 871.8 873.4 873.4 873.8 873.8 874.4
moderate All 849.9 847.4 849.8 849.2 849.3 847.9
moderate Buchan Ness 851.2 850.0 850.7 849.7 850.6 849.8
moderate Fowlsheugh 853.4 853.2 853.4 853.4 851.2 852.2
moderate Forth 862.7 849.9 861.0 860.9 862.9 852.6
moderate St Abbs 836.0 836.8 837.2 835.9 836.9 837.9
poor All 792.9 790.6 792.3 792.7 793.2 791.0
poor Buchan Ness 813.2 813.6 813.9 811.9 813.1 814.5
poor Fowlsheugh 797.8 796.5 795.1 795.7 796.8 795.0
poor Forth 786.6 773.1 785.0 787.8 787.9 776.8
poor St Abbs 778.4 780.6 780.5 780.4 780.1 780.9

Table F. 21. Guillemot. Mean adult body mass at the end of chick-rearing in the baseline and each wind farm scenario for each SPA and all combined for each prey availability, based on heterogeneous prey distribution.

Prey SPA Baseline NnG Inch Alpha Bravo All 4
good All 891.9 889.0 890.8 891.6 891.6 889.6
good Fowlsheugh 880.6 880.2 879.4 880.1 880.7 880.4
good Forth 899.7 888.2 896.8 900.2 899.3 889.2
good St Abbs 901.0 900.8 901.3 900.6 900.5 901.6
moderate All 860.7 858.3 861.2 860.1 860.4 859.2
moderate Fowlsheugh 859.2 859.3 860.6 858.2 859.4 859.3
moderate Forth 854.7 842.9 854.4 854.5 854.1 847.0
moderate St Abbs 866.7 867.3 866.4 866.2 865.9 867.2
poor All 786.2 784.2 786.5 785.6 786.8 785.2
poor Fowlsheugh 782.0 782.8 783.0 781.2 782.9 782.8
poor Forth 769.4 760.4 769.8 769.3 770.5 764.8
poor St Abbs 802.7 802.0 802.2 801.9 802.7 801.8

Table F. 22. Guillemot. Mean change in adult survival (as a percentage point) between each wind farm scenario and the baseline for each SPA and all combined, and for each prey availability, based on homogeneous prey distribution.

Prey SPA NnG Inch Alpha Bravo All 4
good All -0.3 0.0 0.2 0.4 -0.2
good Buchan Ness -0.3 0.2 -0.1 0.2 0.1
good Fowlsheugh -0.4 -0.6 -0.5 0.0 -0.7
good Forth -4.8 -0.3 0.4 0.4 -3.1
good St Abbs 0.5 0.5 0.6 0.8 0.8
moderate All -0.6 0.1 -0.2 -0.1 -0.5
moderate Buchan Ness -0.5 -0.4 -0.8 -0.3 -0.7
moderate Fowlsheugh 0.1 0.1 0.0 -0.8 -0.4
moderate Forth -4.2 -0.4 -0.5 0.2 -3.4
moderate St Abbs 0.2 0.4 0.0 0.2 0.6
poor All -0.9 -0.1 0.0 0.2 -0.8
poor Buchan Ness 0.1 0.2 -0.7 -0.3 0.5
poor Fowlsheugh -0.4 -1.1 -0.9 -0.3 -1.3
poor Forth -6.0 -1.0 0.1 0.0 -4.4
poor St Abbs 1.1 1.1 0.9 1.1 1.2

Table F. 23. Guillemot. Mean change in adult survival (as a percentage point) between each wind farm scenario and the baseline for each SPA and all combined, and for each prey availability, based on heterogeneous prey distribution.

Prey SPA NnG Inch Alpha Bravo All 4
good All -1.0 -0.4 -0.1 -0.1 -0.8
good Fowlsheugh -0.2 -0.3 -0.3 0.0 -0.1
good Forth -6.1 -1.5 0.4 -0.1 -5.3
good St Abbs -0.1 0.3 -0.2 -0.3 0.3
moderate All -1.1 0.1 -0.3 0.0 -0.7
moderate Fowlsheugh -0.3 0.3 -0.7 -0.1 -0.2
moderate Forth -3.3 0.0 0.1 0.1 -2.3
moderate St Abbs 0.3 0.0 0.0 0.0 0.3
poor All -0.9 0.3 -0.2 0.3 -0.4
poor Fowlsheugh 0.4 0.4 -0.2 0.5 0.5
poor Forth -3.8 0.2 0.0 0.4 -2.1
poor St Abbs -0.4 0.1 -0.4 0.0 -0.3

Table F. 24. Guillemot. Mean change in chick survival (as a percentage point) between each wind farm scenario and the baseline for each SPA and all combined, and for each prey availability, based on homogeneous prey distribution.

Prey SPA NnG Inch Alpha Bravo All 4
good All -0.7 -0.7 0.4 -0.3 0.3
good Buchan Ness 0.7 0.2 0.2 0.0 0.2
good Fowlsheugh -1.6 -1.4 1.5 -0.1 0.5
good Forth -0.4 0.2 -1.7 0.2 -0.8
good St Abbs -0.6 -1.0 0.3 -1.1 0.7
moderate All -1.2 0.8 -0.5 -0.5 0.2
moderate Buchan Ness -1.8 1.4 -0.9 -2.5 2.3
moderate Fowlsheugh -1.1 -0.1 -1.5 0.4 -0.1
moderate Forth -3.5 -0.8 -0.2 1.0 -0.8
moderate St Abbs 0.7 2.6 0.7 -1.6 -0.1
poor All -2.7 -0.7 -1.9 -0.2 -4.0
poor Buchan Ness -2.7 -1.6 -1.1 -3.2 -1.8
poor Fowlsheugh -1.9 -0.9 -4.1 -1.6 -6.7
poor Forth -8.3 -1.0 -1.9 2.3 -8.9
poor St Abbs 0.1 0.4 0.4 1.8 1.4

Table F. 25. Guillemot. Mean change in chick survival (as a percentage point) between each wind farm scenario and the baseline for each SPA and all combined, and for each prey availability, based on heterogeneous prey distribution.

Prey SPA NnG Inch Alpha Bravo All 4
good All -0.1 0.7 0.4 0.1 -0.1
good Fowlsheugh -0.2 0.0 -1.2 0.4 -0.9
good Forth -2.7 -0.6 0.8 -0.8 -2.1
good St Abbs 1.8 2.6 2.2 0.1 2.1
moderate All -0.3 -0.4 0.2 0.1 -2.4
moderate Fowlsheugh 0.2 0.3 1.7 -0.8 -3.2
moderate Forth -0.2 0.4 0.0 0.0 -0.4
moderate St Abbs -1.1 -1.8 -1.5 1.4 -2.6
poor All -3.8 -0.2 -0.8 -1.1 -2.1
poor Fowlsheugh -1.1 0.0 -1.8 -0.6 -3.4
poor Forth -12.0 -0.4 0.6 -2.5 -5.4
poor St Abbs -1.8 -0.4 -0.6 -0.8 1.6

F.3.2. The effects of buffer width

The following scenarios were explored:

  • 0km buffer around wind farm
  • 0.5km buffer around wind farm
  • 1km buffer around wind farm

The three scenarios were carried out on all SPAs in three prey availability levels for Neart na Gaoithe wind farm only. The third scenario is a repeat scenario from section F.3.1. For all scenarios, we assumed that 100% of birds that were intending to forage in the wind farm were displaced and for 100% of birds that were intending to forage beyond the wind farm, it acted as a barrier such that they flew around it, not through it.

Adult survival change relative to the baseline can be found in Table F. 26 and Table F. 27 for homogeneous and GPS-derived prey, respectively. Chick survival change relative to the baseline can be found in Table F. 28 and Table F 29 or homogeneous and GPS-derived prey, respectively.

Table F. 26. Guillemot. Mean change in adult survival (as a percentage point) between Neart na Gaoithe scenario and the baseline at three alternative buffer widths, for each SPA and all combined, and for each prey availability, based on homogeneous prey distribution.

Prey SPA Buffer width
0 km 0.5 km 1 km
good All -0.2 -0.2 -0.3
good Buchan Ness -0.6 0.5 -0.3
good Fowlsheugh -0.3 -0.3 -0.4
good Forth -4.0 -4.5 -4.8
good St Abbs 0.6 0.6 0.5
moderate All -0.6 -0.6 -0.6
moderate Buchan Ness -0.9 -1.0 -0.5
moderate Fowlsheugh -0.4 0.3 0.1
moderate Forth -3.2 -3.9 -4.2
moderate St Abbs 0.3 0.1 0.2
poor All -0.9 -0.9 -0.9
poor Buchan Ness 0.4 -0.6 0.1
poor Fowlsheugh -0.2 0.0 -0.4
poor Forth -5.9 -5.5 -6.0
poor St Abbs 0.9 0.7 1.1

Table F. 27. Guillemot. Mean change in adult survival (as a percentage point) between Neart na Gaoithe scenario and the baseline at three alternative buffer widths, for each SPA and all combined, and for each prey availability, based on heterogeneous prey distribution.

Prey SPA Buffer width
0 km 0.5 km 1 km
good All -0.7 -0.9 -1.0
good Fowlsheugh 0.1 0.1 -0.2
good Forth -4.9 -6.3 -6.1
good St Abbs -0.2 -0.1 -0.1
moderate All -0.7 -0.8 -1.1
moderate Fowlsheugh -0.2 -0.4 -0.3
moderate Forth -2.4 -2.3 -3.3
moderate St Abbs 0.2 0.3 0.3
poor All -0.5 -0.7 -0.9
poor Fowlsheugh 0.3 0.6 0.4
poor Forth -3.2 -3.3 -3.8
poor St Abbs 0.9 -0.4 -0.4

Table F. 28. Guillemot. Mean change in chick survival (as a percentage point) between Neart na Gaoithe scenario and the baseline at three alternative buffer widths, for each SPA and all combined, and for each prey availability, based on homogeneous prey distribution.

Prey SPA Buffer width
0 km 0.5 km 1 km
good All -0.1 -0.9 -0.7
good Buchan Ness 0.9 0.9 0.7
good Fowlsheugh 0.4 0.0 -1.6
good Forth -0.6 -1.2 -0.4
good St Abbs -1.0 -2.7 -0.6
moderate All 0.3 -1.2 -1.2
moderate Buchan Ness 1.6 -0.7 -1.8
moderate Fowlsheugh -0.3 -1.4 -1.1
moderate Forth -1.4 -3.1 -3.5
moderate St Abbs 1.5 0.0 0.7
poor All -4.1 -3.2 -2.7
poor Buchan Ness -1.8 -4.0 -2.7
poor Fowlsheugh -4.7 -3.3 -1.9
poor Forth -8.7 -6.4 -8.3
poor St Abbs -1.8 -0.6 0.1

Table F. 29 Guillemot. Mean change in chick survival (as a percentage point) between Neart na Gaoithe scenario and the baseline at three alternative buffer widths, for each SPA and all combined, and for each prey availability, based on heterogeneous prey distribution.

Prey SPA Buffer width
0 km 0.5 km 1 km
good All -0.8 -0.1 -0.1
good Fowlsheugh -1.4 -0.3 -0.2
good Forth -2.5 -1.2 -2.7
good St Abbs 1.0 1.0 1.8
moderate All -1.8 -1.4 -0.3
moderate Fowlsheugh -0.2 -2.8 0.2
moderate Forth -2.3 0.0 -0.2
moderate St Abbs -3.4 -0.6 -1.1
poor All -3.7 -2.6 -3.8
poor Fowlsheugh -3.5 -0.9 -1.1
poor Forth -9.1 -7.6 -12.0
poor St Abbs -0.4 -1.5 -1.8

F.3.3. The effects of percentage of birds displaced

The following scenarios were explored:

  • 50% of birds displaced and 50% for whom the wind farm acted as a barrier
  • 0% of birds displaced and 100% for whom the wind farm acted as a barrier
  • 100% of birds displaced and 0% for whom the wind farm acted as a barrier

The three scenarios were carried out on all SPAs in three prey availability levels for all wind farms combined. The results were compared with equivalent scenarios where level for displacement and barrier effect were both 100% (repeat of scenario presented in Section F.3.1). For all scenarios, we assumed a buffer with of 1km.

Adult survival change relative to the baseline can be found Table F. 30 and Table F. 31 for homogeneous and GPS-derived prey, respectively. Chick survival change relative to the baseline can be found in Table F. 32 and Table F. 33 for homogeneous and GPS-derived prey, respectively.

Table F. 30. Guillemot. Mean change in adult survival (as a percentage point) between scenario of all four wind farms combined and the baseline in relation to alternative displacement and barrier percentages, for each SPA and all combined, and for each prey availability, based on homogeneous prey distribution.

Prey SPA Displacement/Barrier %
100/100 50/50 0/100 100/0
good All -0.2 0.1 -0.2 0.2
good Buchan Ness 0.1 0.2 -0.2 0.1
good Fowlsheugh -0.7 -0.3 -0.4 -0.1
good Forth -3.1 -1.0 -3.3 -0.1
good St Abbs 0.8 0.6 0.4 0.6
moderate All -0.5 -0.2 -0.7 0.1
moderate Buchan Ness -0.7 -0.6 -0.3 -0.6
moderate Fowlsheugh -0.4 0.0 -0.6 -0.3
moderate Forth -3.4 -1.3 -3.0 -0.4
moderate St Abbs 0.6 0.1 -0.2 0.9
poor All -0.8 -0.7 -0.8 0.2
poor Buchan Ness 0.5 0.1 1.1 0.6
poor Fowlsheugh -1.3 -1.2 -0.8 -0.6
poor Forth -4.4 -2.1 -5.6 -0.8
poor St Abbs 1.2 0.0 1.1 1.3

Table F. 31 Guillemot. Mean change in adult survival (as a percentage point) between of all four wind farms combined and the baseline in relation to alternative displacement and barrier percentages, for each SPA and all combined, and for each prey availability, based on heterogeneous prey distribution.

Prey SPA Displacement/Barrier %
100/100 50/50 0/100 100/0
good All -0.8 -0.7 -1.0 -0.1
good Fowlsheugh -0.1 -0.3 -0.4 0.1
good Forth -5.3 -3.3 -5.8 -0.6
good St Abbs 0.3 -0.2 -0.1 -0.2
moderate All -0.7 -0.3 -0.8 0.0
moderate Fowlsheugh -0.2 -0.4 -0.2 -0.2
moderate Forth -2.3 -0.8 -2.4 -0.1
moderate St Abbs 0.3 0.4 0.2 0.2
poor All -0.4 -0.3 -0.6 0.6
poor Fowlsheugh 0.5 0.1 -0.2 1.0
poor Forth -2.1 -0.7 -2.7 0.4
poor St Abbs -0.3 -0.6 0.5 0.1

Table F. 32. Guillemot. Mean change in chick survival (as a percentage point) between of all four wind farms combined and the baseline in relation to alternative displacement and barrier percentages, for each SPA and all combined, and for each prey availability, based on homogeneous prey distribution.

Prey SPA Displacement/Barrier %
100/100 50/50 0/100 100/0
good All 0.3 -0.8 -0.7 -0.2
good Buchan Ness 0.2 -0.9 0.2 0.9
good Fowlsheugh 0.5 -0.1 -1.3 -1.2
good Forth -0.8 -1.2 -1.4 -1.2
good St Abbs 0.7 -1.4 0.0 1.2
moderate All 0.2 -0.7 -1.8 0.9
moderate Buchan Ness 2.3 -2.9 -0.2 2.3
moderate Fowlsheugh -0.1 -0.6 -1.2 -0.5
moderate Forth -0.8 -2.7 -3.7 1.2
moderate St Abbs -0.1 2.1 -2.3 1.5
poor All -4.0 -1.7 -2.4 -1.1
poor Buchan Ness -1.8 -0.7 -0.9 2.3
poor Fowlsheugh -6.7 -2.0 -1.6 -3.2
poor Forth -8.9 -5.2 -10.5 -3.1
poor St Abbs 1.4 0.3 1.2 0.8

Table F. 33. Guillemot. Mean change in chick survival (as a percentage point) between of all four wind farms combined and the baseline in relation to alternative displacement and barrier percentages, for each SPA and all combined, and for each prey availability, based on heterogeneous prey distribution.

Prey SPA Displacement/Barrier %
100/100 50/50 0/100 100/0
good All -0.1 -0.2 -0.5 0.5
good Fowlsheugh -0.9 -0.4 -0.1 0.5
good Forth -2.1 -1.7 -0.8 -1.4
good St Abbs 2.1 1.0 -0.7 1.6
moderate All -2.4 -1.3 -2.5 -0.1
moderate Fowlsheugh -3.2 -0.4 -1.3 -0.1
moderate Forth -0.4 0.2 -4.3 1.0
moderate St Abbs -2.6 -3.3 -2.7 -1.0
poor All -2.1 -1.6 -1.3 -0.2
poor Fowlsheugh -3.4 -0.4 -3.3 -1.8
poor Forth -5.4 -2.5 -4.5 -0.6
poor St Abbs 1.6 -2.6 3.4 2.2

F.4. Razorbill Alca torda

Three SPAs are designated for this species in the region (Fowlsheugh, Forth Islands and St Abb's Head to Fastcastle). For each SPA, and all SPAs combined, we carried out three sets of scenarios, presented in sections F.4.1, F.4.2 and F.4.3. Models based on heterogeneous prey included birds from all SPAs, but outputs were only recorded for Forth Islands, because of the lack of GPS data available from Fowlsheugh at St Abb's Head to Fastcastle.

F.4.1. The effects of wind farms and prey availability

The following scenarios were explored:

  • Effect of wind farm:
    • No wind farms (the baseline scenario)
    • each of the four individual wind farms separately
    • the combined impact of all four wind farms
  • Overall prey availability
    • Good
    • Moderate
    • Poor

The above scenarios resulted in a total of 18 scenarios (six wind farms scenarios in three prey availabilities). For all scenarios, we assumed a 1km exclusion buffer, and that 100% of birds that were intending to forage in the wind farm were displaced and for 100% of birds that were intending to forage beyond the wind farm, it acted as a barrier such that they flew around it, not through it.

Figure F. 9a shows the distribution of birds from all SPAs in the baseline scenario and Figure F. 9b the distribution of birds from all SPAs in the scenario with all four wind farms under moderate prey availability and homogeneous prey distribution. These two scenarios are shown again in Figure F. 10a and Figure F. 10b based on heterogeneous prey.

The number of birds displaced and for whom the wind farm(s) acted as a barrier is shown for all 18 scenarios in Table F. 34 under homogeneous prey distribution and Table F. 35 with heterogeneous prey.

Mean adult body mass is presented as a histogram plot showing the difference between the baseline and the four wind farm scenario for all SPAs combined under moderate prey availability with homogeneous Figure F. 11 and heterogeneous prey Figure F.12. Mean adult mass at the end of the breeding season is given for all 18 scenarios is given in Table F. 36 (homogeneous prey) and Table F.37 (heterogeneous prey). Adult survival change relative to the baseline can be found in Table F. 38 (homogeneous prey) and Table F. 39 (heterogeneous prey). Finally, chick survival change relative to the baseline can be found in Table F. 40 (homogeneous prey) and Table F41.

Figure F. 9. Razorbill. Distribution of birds from each SPA a) in the absence of wind farms and b) with all four wind farms present, under moderate prey availability and homogeneous prey distribution.

Figure F. 9

Figure F. 10 Razorbill. Distribution of birds from each SPA a) in the absence of wind farms and b) with all four wind farms present, under moderate prey availability and heterogeneous prey distribution.

Figure F. 10

Table F. 34. Razorbill. Mean across time steps percentage of the population displaced and for whom the wind farm(s) were a barrier for each wind farm scenario under three prey availabilities for each SPA and all four SPAs combined, based on homogeneous prey distribution.

Prey SPA Baseline NnG Inch Alpha Bravo All 4
Disp Barr Disp Barr Disp Barr Disp Barr Disp Barr Disp Barr
good All 0.0 0.0 0.3 5.1 0.6 2.0 1.2 0.8 0.4 0.7 2.4 5.4
good Fowlsheugh 0.0 0.0 0.0 0.0 0.4 0.2 1.2 1.4 0.6 1.0 2.0 1.0
good Forth 0.0 0.0 0.6 13.4 1.1 4.8 2.0 0.3 0.3 0.6 3.4 13.1
good St Abbs 0.0 0.0 0.8 1.6 0.0 0.0 0.0 0.0 0.0 0.0 0.8 0.8
moderate All 0.0 0.0 0.3 5.1 0.5 2.0 1.2 0.9 0.4 0.7 2.3 5.6
moderate Fowlsheugh 0.0 0.0 0.0 0.0 0.4 0.2 1.2 1.4 0.6 1.0 1.8 1.2
moderate Forth 0.0 0.0 0.9 13.6 0.9 4.8 1.7 0.3 0.3 0.6 3.4 13.6
moderate St Abbs 0.0 0.0 0.8 1.6 0.0 0.0 0.0 0.0 0.0 0.0 0.8 0.0
poor All 0.0 0.0 0.3 5.1 0.6 2.0 1.2 0.9 0.5 0.7 2.5 5.6
poor Fowlsheugh 0.0 0.0 0.0 0.0 0.4 0.4 1.0 1.6 0.8 1.0 2.0 1.0
poor Forth 0.0 0.0 0.9 13.4 1.1 4.8 2.0 0.3 0.3 0.6 3.7 13.6
poor St Abbs 0.0 0.0 0.8 1.6 0.0 0.0 0.0 0.0 0.0 0.0 0.8 0.8

Table F. 35. Razorbill. Mean across time steps percentage of the population displaced and for whom the wind farm(s) were a barrier for each wind farm scenario under three prey availabilities for Forth Islands SPA, based on heterogeneous prey distribution.

Prey SPA Baseline NnG Inch Alpha Bravo All 4
Disp Barr Disp Barr Disp Barr Disp Barr Disp Barr Disp Barr
good Forth 0.0 0.0 0.6 13.4 1.1 4.8 1.7 0.3 0.3 0.6 3.4 13.4
moderate Forth 0.0 0.0 0.9 13.9 1.1 4.8 2.0 0.3 0.3 0.6 3.7 13.6
poor Forth 0.0 0.0 0.9 13.4 1.1 4.8 1.7 0.3 0.3 0.6 3.7 13.9

Figure F. 11. Razorbill. Histogram of distribution of adult body mass at Forth Islands SPA at the end of the chick-rearing period under moderate conditions with homogeneous prey distribution, with purple bars denoting the distribution of masses shared between baseline scenario and scenario with all four wind farms, blue denoting the distribution in the scenario with all four wind farms not the baseline, and pink denoting the distribution in the baseline and not the scenario with all four wind farms.

Figure F. 11

Figure F. 12. Razorbill. Histogram of distribution of adult body mass at Forth Islands SPA at the end of the chick-rearing period under moderate conditions with heterogeneous prey distribution, with purple bars denoting the distribution of masses shared between baseline scenario and scenario with all four wind farms, blue denoting the distribution in the scenario with all four wind farms not the baseline, and pink denoting the distribution in the baseline and not the scenario with all four wind farms.

Figure F. 12

Table F. 36. Razorbill. Mean adult body mass at the end of chick-rearing in the baseline and each wind farm scenario for each SPA and all combined for each prey availability, based on homogeneous prey distribution.

Prey SPA Baseline NnG Inch Alpha Bravo All 4
good All 577.2 577.0 577.6 577.3 577.3 575.6
good Fowlsheugh 575.8 576.4 576.7 576.4 575.7 574.6
good Forth 573.8 572.8 573.7 573.6 574.4 571.6
good St Abbs 591.7 591.2 592.0 591.3 591.1 591.0
moderate All 553.9 552.7 553.3 553.4 553.5 552.6
moderate Fowlsheugh 558.4 558.3 559.0 558.7 558.4 558.5
moderate Forth 543.8 541.4 542.0 542.3 542.6 540.2
moderate St Abbs 564.6 562.5 562.8 564.0 564.6 564.3
poor All 535.4 534.4 534.4 533.8 534.9 533.5
poor Fowlsheugh 543.6 542.4 542.8 540.9 542.5 540.9
poor Forth 525.5 524.7 524.3 524.8 525.7 524.2
poor St Abbs 531.2 530.2 529.8 531.6 531.0 530.5

Table F. 37 Razorbill. Mean adult body mass at the end of chick-rearing in the baseline and each wind farm scenario, for Forth Islands SPA and for each prey availability, based on heterogeneous prey distribution.

Prey SPA Baseline NnG Inch Alpha Bravo All 4
good Forth 595.5 595.7 595.6 595.8 595.8 595.9
moderate Forth 551.5 548.3 551.4 551.0 552.1 549.0
poor Forth 525.4 524.7 525.9 526.0 526.2 524.1

Table F. 38. Razorbill. Mean change in adult survival (as a percentage point) between each wind farm scenario and the baseline for each SPA and all combined, and for each prey availability, based on homogeneous prey distribution.

Prey SPA NnG Inch Alpha Bravo All 4
good All -0.2 0.3 0.2 0.1 -0.9
good Fowlsheugh 0.4 0.6 0.5 0.1 -0.6
good Forth -0.9 0.0 -0.1 0.4 -1.5
good St Abbs -0.5 0.4 -0.3 -0.9 -0.4
moderate All -0.7 -0.3 -0.3 -0.3 -0.8
moderate Fowlsheugh 0.1 0.6 0.3 0.0 0.2
moderate Forth -1.5 -0.8 -0.9 -0.8 -2.0
moderate St Abbs -1.4 -1.5 -0.8 0.0 -0.5
poor All -0.8 -0.8 -1.0 -0.3 -1.4
poor Fowlsheugh -1.0 -0.6 -2.4 -0.9 -2.2
poor Forth -0.9 -1.1 -0.6 0.0 -1.5
poor St Abbs -0.8 -1.2 0.5 0.1 -0.5

Table F. 39. Razorbill. Mean change in adult survival (as a percentage point) between each wind farm scenario and the baseline for Forth Islands SPA and for each prey availability, based on heterogeneous prey distribution.

Prey SPA NnG Inch Alpha Bravo All 4
good Forth 0.2 -0.1 0.4 0.5 0.5
moderate Forth -2.1 -0.4 -0.6 0.3 -1.9
poor Forth -0.9 0.2 0.4 0.4 -1.4

Table F. 40. Razorbill. Mean change in chick survival (as a percentage point) between each wind farm scenario and the baseline for each SPA and all combined, and for each prey availability, based on homogeneous prey distribution.

Prey SPA NnG Inch Alpha Bravo All 4
good All 0.3 0.3 -0.8 0.6 -2.4
good Fowlsheugh -0.2 -0.3 -2.5 0.4 -3.9
good Forth 0.3 0.5 0.8 0.0 -2.7
good St Abbs 1.9 2.5 1.6 2.9 4.1
moderate All -3.2 -1.3 -1.0 -2.5 -4.1
moderate Fowlsheugh -1.6 0.7 0.2 -1.1 -2.1
moderate Forth -5.7 -4.1 -3.3 -4.6 -7.5
moderate St Abbs -1.9 -1.3 1.0 -2.2 -1.9
poor All -1.2 -0.4 -0.6 -1.8 -0.8
poor Fowlsheugh 0.2 0.6 -0.6 -2.4 0.7
poor Forth -3.3 -1.4 -1.9 -1.6 -3.8
poor St Abbs -1.0 -1.3 3.2 0.0 1.3

Table F. 41. Razorbill. Mean change in chick survival (as a percentage point) between each wind farm scenario and the baseline for Forth Islands SPA and all combined, for each prey availability, based on heterogeneous prey distribution.

Prey SPA NnG Inch Alpha Bravo All 4
good Forth -0.1 -0.2 0.6 -0.1 0.0
moderate Forth -1.6 0.9 -0.2 2.4 -3.0
poor Forth -2.3 2.6 1.7 0.2 -0.6

F.4.2. The effects of buffer width

The following scenarios were explored:

  • 0km buffer around wind farm
  • 0.5km buffer around wind farm
  • 1km buffer around wind farm

The three scenarios were carried out on all SPAs in three prey availability levels for Neart na Gaoithe wind farm only. The third scenario is a repeat scenario from section F.4.1. For all scenarios, we assumed that 100% of birds that were intending to forage in the wind farm were displaced and for 100% of birds that were intending to forage beyond the wind farm, it acted as a barrier such that they flew around it, not through it.

Adult survival change relative to the baseline can be found in Table F. 42 and Table F. 43 for homogeneous and GPS-derived prey, respectively. Chick survival change relative to the baseline can be found in Table F. 44 and Table F 45 or homogeneous and GPS-derived prey, respectively.

Table F. 42. Razorbill. Mean change in adult survival (as a percentage point) between Neart na Gaoithe scenario and the baseline at three alternative buffer widths, for each SPA and all combined, and for each prey availability, based on homogeneous prey distribution.

Prey SPA Buffer width
0 km 0.5 km 1 km
good All -0.1 -0.3 -0.2
good Fowlsheugh 0.5 0.3 0.4
good Forth -0.8 -0.9 -0.9
good St Abbs -0.5 -1.2 -0.5
moderate All -0.5 -0.6 -0.7
moderate Fowlsheugh -0.2 0.4 0.1
moderate Forth -0.8 -1.3 -1.5
moderate St Abbs -0.9 -1.7 -1.4
poor All -0.9 -0.3 -0.8
poor Fowlsheugh -0.9 0.3 -1.0
poor Forth -1.2 -0.5 -0.9
poor St Abbs -1.2 -1.3 -0.8

Table F. 43. Razorbill. Mean change in adult survival (as a percentage point) between Neart na Gaoithe scenario and the baseline at three alternative buffer widths, for Forth Islands SPA for each prey availability, based on heterogeneous prey distribution.

Prey SPA Buffer width
0 km 0.5 km 1 km
good Forth 0.2 0.2 0.2
moderate Forth -1.5 -1.3 -2.1
poor Forth -1.3 -0.5 -0.9

Table F. 44 . Razorbill. Mean change in chick survival (as a percentage point) between Neart na Gaoithe scenario and the baseline at three alternative buffer widths, for each SPA and all combined, and for each prey availability, based on homogeneous prey distribution.

Prey SPA Buffer width
0 km 0.5 km 1 km
good All 1.1 0.0 0.3
good Fowlsheugh 0.5 -0.8 -0.2
good Forth 1.7 0.0 0.3
good St Abbs 1.6 3.5 1.9
moderate All -0.6 -0.7 -3.2
moderate Fowlsheugh -0.7 1.3 -1.6
moderate Forth -1.4 -3.2 -5.7
moderate St Abbs 1.6 -1.6 -1.9
poor All 1.8 3.1 -1.2
poor Fowlsheugh 3.7 7.2 0.2
poor Forth -0.8 -1.0 -3.3
poor St Abbs 1.9 -1.3 -1.0

Table F. 45. Razorbill. Mean change in chick survival (as a percentage point) between Neart na Gaoithe scenario and the baseline at three alternative buffer widths, for Forth Islands SPA for each prey availability, based on heterogeneous prey distribution.

Prey SPA Buffer width
0 km 0.5 km 1 km
good Forth -0.1 0.1 -0.1
moderate Forth -1.6 0.7 -1.6
poor Forth -1.7 0.0 -2.3

F.4.3. The effects of percentage of birds displaced

The following scenarios were explored:

  • 50% of birds displaced and 50% for whom the wind farm acted as a barrier
  • 0% of birds displaced and 100% for whom the wind farm acted as a barrier
  • 100% of birds displaced and 0% for whom the wind farm acted as a barrier

The three scenarios were carried out on all SPAs in three prey availability levels for all wind farms combined. The results were compared with equivalent scenarios where level for displacement and barrier effect were both 100% (repeat of scenario presented in Section F.4.1). For all scenarios, we assumed a buffer with of 1km.

Adult survival change relative to the baseline can be found Table F. 46 and Table F. 47 for homogeneous and GPS-derived prey, respectively. Chick survival change relative to the baseline can be found in Table F. 48 and Table F. 49 for homogeneous and GPS-derived prey, respectively.

Table F. 46. Razorbill. Mean change in adult survival (as a percentage point) between scenario of all four wind farms combined and the baseline in relation to alternative displacement and barrier percentages, for each SPA and all combined, and for each prey availability, based on homogeneous prey distribution.

Prey SPA Displacement/Barrier %
100/100 50/50 0/100 100/0
good All -0.9 0.1 -0.3 0.2
good Fowlsheugh -0.6 0.1 0.7 0.1
good Forth -1.5 0.3 -1.6 0.6
good St Abbs -0.4 -1.3 -0.5 -0.9
moderate All -0.8 -0.1 -0.5 -0.2
moderate Fowlsheugh 0.2 0.4 0.0 -0.2
moderate Forth -2.0 -0.8 -1.0 -0.3
moderate St Abbs -0.5 0.4 0.0 -0.7
poor All -1.4 -0.7 -1.4 -0.3
poor Fowlsheugh -2.2 -0.8 -2.0 -0.8
poor Forth -1.5 -0.2 -1.6 -0.6
poor St Abbs -0.5 -2.5 -0.1 1.0

Table F. 47. Razorbill. Mean change in adult survival (as a percentage point) between of all four wind farms combined and the baseline in relation to alternative displacement and barrier percentages, for Forth Islands SPA for each prey availability, based on heterogeneous prey distribution.

Prey SPA Displacement/Barrier %
100/100 50/50 0/100 100/0
good Forth 0.5 -0.2 -0.1 0.9
moderate Forth -1.9 -0.3 -2.1 0.1
poor Forth -1.4 0.5 -0.2 -0.2

Table F. 48. Razorbill. Mean change in chick survival (as a percentage point) between of all four wind farms combined and the baseline in relation to alternative displacement and barrier percentages, for each SPA and all combined, and for each prey availability, based on homogeneous prey distribution.

Prey SPA Displacement/Barrier %
100/100 50/50 0/100 100/0
good All -2.4 -1.3 -1.3 -0.1
good Fowlsheugh -3.9 -3.4 -3.4 -1.1
good Forth -2.7 0.5 1.0 0.5
good St Abbs 4.1 1.9 0.0 1.9
moderate All -4.1 -1.2 -1.1 -1.6
moderate Fowlsheugh -2.1 0.2 1.4 -2.1
moderate Forth -7.5 -4.7 -4.6 -2.3
moderate St Abbs -1.9 3.5 -1.3 2.2
poor All -0.8 -2.4 -0.7 1.4
poor Fowlsheugh 0.7 0.0 -0.8 1.9
poor Forth -3.8 -3.5 -0.6 0.8
poor St Abbs 1.3 -8.6 -0.6 1.0

Table F. 49. Razorbill. Mean change in chick survival (as a percentage point) between of all four wind farms combined and the baseline in relation to alternative displacement and barrier percentages for Forth Islands SPA for each prey availability, based on heterogeneous prey distribution.

Prey SPA Displacement/Barrier %
100/100 50/50 0/100 100/0
good Forth 0.0 -0.5 -0.2 -0.2
moderate Forth -3.0 0.9 -1.9 0.5
poor Forth -0.6 0.0 2.4 -0.1

F.5. Atlantic puffin Fratercula arctica

One SPA is designated for this species in the region (Forth Islands). We carried out three sets of scenarios, presented in sections F.5.1, F.5.2 and F.5.3.

F.5.1. The effects of wind farms and prey availability

The following scenarios were explored:

  • Effect of wind farm:
    • No wind farms (the baseline scenario)
    • each of the four individual wind farms separately
    • the combined impact of all four wind farms
  • Overall prey availability
    • Good
    • Moderate
    • Poor

The above scenarios resulted in a total of 18 scenarios (six wind farms scenarios in three prey availabilities). For all scenarios, we assumed a 1km exclusion buffer, and that 100% of birds that were intending to forage in the wind farm were displaced and for 100% of birds that were intending to forage beyond the wind farm, it acted as a barrier such that they flew around it, not through it.

Figure F. 13a shows the distribution of birds from all SPAs in the baseline scenario and Figure F. 13b the distribution of birds from all SPAs in the scenario with all four wind farms under moderate prey availability and homogeneous prey distribution. These two scenarios are shown again in Figure F. 14a and Figure F. 14b based on heterogeneous prey.

The number of birds displaced and for whom the wind farm(s) acted as a barrier is shown for all 18 scenarios in Table F. 50 under homogeneous prey distribution and Table F. 51 with heterogeneous prey.

Mean adult body mass is presented as a histogram plot showing the difference between the baseline and the four wind farm scenario for all SPAs combined under moderate prey availability with homogeneous Figure F. 15 and heterogeneous prey Figure F.16. Mean adult mass at the end of the breeding season is given for all 18 scenarios is given in Table F. 52 (homogeneous prey) and Table F.53 (heterogeneous prey). Adult survival change relative to the baseline can be found in Table F. 54 (homogeneous prey) and Table F. 55 (heterogeneous prey). Finally, chick survival change relative to the baseline can be found in Table F. 56 (homogeneous prey) and Table F57.

Figure F. 13. Puffin. Distribution of birds from Forth Islands SPA a) in the absence of wind farms and b) with all four wind farms present, under moderate prey availability and homogeneous prey distribution.

Figure F. 13

Figure F. 14. Puffin.Distribution of birds from Forth Islands SPA a) in the absence of wind farms and b) with all four wind farms present, under moderate prey availability and heterogeneous prey distribution.

Figure F. 14

Table F. 50. Puffin. Mean across time steps percentage of the population displaced and for whom the wind farm(s) were a barrier for each wind farm scenario under three prey availabilities for Forth Islands SPA, based on homogeneous prey distribution.

Prey SPA Baseline NnG Inch Alpha Bravo All 4
Disp Barr Disp Barr Disp Barr Disp Barr Disp Barr Disp Barr
goo Forth 0.0 0.0 0.5 38.8 5.8 19.3 2.4 0.2 0.3 0.6 8.7 32.6
modedrate Forth 0.0 0.0 0.4 38.8 5.8 19.3 2.5 0.2 0.3 0.7 8.7 32.6
poor Forth 0.0 0.0 0.5 38.9 5.9 19.3 2.5 0.2 0.3 0.6 8.6 32.6

Table F. 51. Puffin. Mean across time steps percentage of the population displaced and for whom the wind farm(s) were a barrier for each wind farm scenario under three prey availabilities for Forth Islands SPA, based on heterogeneous prey distribution.

Prey SPA Baseline NnG Inch Alpha Bravo All 4
Disp Barr Disp Barr Disp Barr Disp Barr Disp Barr Disp Barr
good Forth 0.0 0.0 0.4 38.9 5.8 19.3 2.5 0.2 0.3 0.6 8.7 32.6
moderate Forth 0.0 0.0 0.5 38.9 5.8 19.3 2.4 0.2 0.3 0.6 8.6 32.6
poor Forth 0.0 0.0 0.5 38.9 5.8 19.3 2.5 0.2 0.3 0.6 8.6 32.6

Figure F. 15. Puffin. Histogram of distribution of adult body mass at Forth Islands SPA at the end of the chick-rearing period under moderate conditions with homogeneous prey distribution, with purple bars denoting the distribution of masses shared between baseline scenario and scenario with all four wind farms, blue denoting the distribution in the scenario with all four wind farms not the baseline, and pink denoting the distribution in the baseline and not the scenario with all four wind farms.

Figure F. 15

Figure F. 16. Puffin. Histogram of distribution of adult body mass at Forth Islands SPA at the end of the chick-rearing period under moderate conditions with heterogeneous prey distribution, with purple bars denoting the distribution of masses shared between baseline scenario and scenario with all four wind farms, blue denoting the distribution in the scenario with all four wind farms not the baseline, and pink denoting the distribution in the baseline and not the scenario with all four wind farms.

Figure F. 16

Table F. 52: Mean adult body mass at the end of chick-rearing in the baseline and each wind farm scenario for Forth Islands SPA and for each prey availability, based on homogeneous prey distribution.

Prey SPA Baseline NnG Inch Alpha Bravo All 4
good Forth 370.6 365.1 368.3 370.4 371.7 364.6
moderate Forth 359.7 351.4 355.1 357.3 360.3 350.5
poor Forth 341.9 332.3 336.5 340.7 341.8 331.7

Table F. 53: Mean adult body mass at the end of chick-rearing in the baseline and each wind farm scenario, for Forth Islands SPA and for each prey availability, based on heterogeneous prey distribution.

Prey SPA Baseline NnG Inch Alpha Bravo All 4
good Forth 390.7 390.2 390.2 390.5 390.8 390.1
moderate Forth 357.6 348.4 355.2 355.9 357.2 348.3
poor Forth 348.1 339.2 344.5 346.7 349.0 338.4

Table F. 54. Puffin. Mean change in adult survival (as a percentage point) between each wind farm scenario and the baseline for Forth Islands SPA and for each prey availability, based on homogeneous prey distribution.

Prey SPA NnG Inch Alpha Bravo All 4
good Forth -3.1 -1.3 -0.2 0.4 -3.4
moderate Forth -5.2 -2.8 -1.3 0.5 -5.8
poor Forth -6.4 -3.5 -1.0 -0.3 -6.8

Table F. 55. Puffin. Mean change in adult survival (as a percentage point) between each wind farm scenario and the baseline for Forth Islands SPA and for each prey availability, based on heterogeneous prey distribution.

Prey SPA NnG Inch Alpha Bravo All 4
good Forth -2.9 -2.7 -1.4 0.0 -3.4
moderate Forth -5.8 -1.4 -0.8 -0.2 -6.0
poor Forth -6.2 -2.5 -0.9 0.5 -6.9

Table F. 56. Puffin. Mean change in chick survival (as a percentage point) between each wind farm scenario and the baseline for Forth Islands SPA and for each prey availability, based on homogeneous prey distribution.

Prey SPA NnG Inch Alpha Bravo All 4
good Forth -1.9 -0.5 0.3 0.1 -1.5
moderate Forth -9.4 -4.2 -1.3 1.9 -10.0
poor Forth -22.5 -11.4 -5.0 -1.5 -24.7

Table F. 57. Puffin.: Mean change in chick survival (as a percentage point) between each wind farm scenario and the baseline for Forth Islands SPA and for each prey availability, based on heterogeneous prey distribution.

Prey SPA NnG Inch Alpha Bravo All 4
good Forth -0.4 -0.4 -0.1 -0.2 -0.2
moderate Forth -11.7 -1.2 -1.0 -0.8 -12.3
poor Forth -16.9 -5.6 -2.0 1.6 -19.3

F.5.2. The effects of buffer width

The following scenarios were explored:

  • 0km buffer around wind farm
  • 0.5km buffer around wind farm
  • 1km buffer around wind farm

The three scenarios were carried out on all SPAs in three prey availability levels for Neart na Gaoithe wind farm only. The third scenario is a repeat scenario from section F.5.1. For all scenarios, we assumed that 100% of birds that were intending to forage in the wind farm were displaced and for 100% of birds that were intending to forage beyond the wind farm, it acted as a barrier such that they flew around it, not through it.

Adult survival change relative to the baseline can be found in Table F. 58 and Table F. 59 for homogeneous and GPS-derived prey, respectively. Chick survival change relative to the baseline can be found in Table F. 60 and Table F 61 or homogeneous and GPS-derived prey, respectively.

Table F. 58. Puffin.: Mean change in adult survival (as a percentage point) between Neart na Gaoithe scenario and the baseline at three alternative buffer widths, for Forth Islands SPA for each prey availability, based on homogeneous prey distribution.

Prey SPA Buffer width
0 km 0.5 km 1 km
good Forth -2.5 -2.2 -3.1
moderate Forth -4.1 -3.5 -5.2
poor Forth -4.2 -4.8 -6.4

Table F. 59. Puffin.: Mean change in adult survival (as a percentage point) between Neart na Gaoithe scenario and the baseline at three alternative buffer widths, for Forth Islands SPA for each prey availability, based on heterogeneous prey distribution.

Prey SPA Buffer width
0 km 0.5 km 1 km
good Forth -2.0 -1.1 -2.9
moderate Forth -4.7 -4.1 -5.8
poor Forth -4.0 -5.0 -6.2

Table F. 60. Puffin. Mean change in chick survival (as a percentage point) between Neart na Gaoithe scenario and the baseline at three alternative buffer widths, for Forth Islands SPA for each prey availability, based on homogeneous prey distribution.

Prey SPA Buffer width
0 km 0.5 km 1 km
good Forth -1.8 -1.4 -1.9
moderate Forth -6.8 -5.5 -9.4
poor Forth -16.2 -18.2 -22.5

Table F. 61. Puffin. Mean change in chick survival (as a percentage point) between Neart na Gaoithe scenario and the baseline at three alternative buffer widths, for Forth Islands SPA for each prey availability, based on heterogeneous prey distribution.

Prey SPA Buffer width
0 km 0.5 km 1 km
good Forth -0.2 -0.4 -0.4
moderate Forth -8.9 -7.7 -11.7
poor Forth -10.9 -13.4 -16.9

F.5.3. The effects of percentage of birds displaced

The following scenarios were explored:

  • 50% of birds displaced and 50% for whom the wind farm acted as a barrier
  • 0% of birds displaced and 100% for whom the wind farm acted as a barrier
  • 100% of birds displaced and 0% for whom the wind farm acted as a barrier

The three scenarios were carried out on all SPAs in three prey availability levels for all wind farms combined. The results were compared with equivalent scenarios where level for displacement and barrier effect were both 100% (repeat of scenario presented in Section F.5.1). For all scenarios, we assumed a buffer with of 1km.

Adult survival change relative to the baseline can be found Table F. 62 and Table F. 63 for homogeneous and GPS-derived prey, respectively. Chick survival change relative to the baseline can be found in Table F. 64 and Table F. 65 for homogeneous and GPS-derived prey, respectively.

Table F. 62. Puffin. Mean change in adult survival (as a percentage point) between scenario of all four wind farms combined and the baseline in relation to alternative displacement and barrier percentages, for Forth Islands SPA for each prey availability, based on homogeneous prey distribution.

Prey SPA Displacement/Barrier %
100/100 50/50 0/100 100/0
good Forth -3.4 -2.1 -3.7 0.3
moderate Forth -5.8 -3.5 -5.9 -0.6
poor Forth -6.8 -3.5 -6.5 -0.9

Table F. 63. Puffin. Mean change in adult survival (as a percentage point) between of all four wind farms combined and the baseline in relation to alternative displacement and barrier percentages, for Forth Islands SPA for each prey availability, based on heterogeneous prey distribution.

Prey SPA Displacement/Barrier %
100/100 50/50 0/100 100/0
good Forth -3.4 -2.3 -4.0 -0.6
moderate Forth -6.0 -3.6 -5.3 -0.3
poor Forth -6.9 -4.1 -6.8 -0.5

Table F. 64. Puffin. Mean change in chick survival (as a percentage point) between of all four wind farms combined and the baseline in relation to alternative displacement and barrier percentages, for Forth Islands SPA and for each prey availability, based on homogeneous prey distribution.

Prey SPA Displacement/Barrier %
100/100 50/50 0/100 100/0
good Forth -1.5 -0.2 -2.7 0.4
moderate Forth -10.0 -4.4 -9.6 0.6
poor Forth -24.7 -12.4 -23.2 -5.0

Table F. 65. Puffin. Mean change in chick survival (as a percentage point) between of all four wind farms combined and the baseline in relation to alternative displacement and barrier percentages for Forth Islands SPA for each prey availability, based on heterogeneous prey distribution.

Prey SPA Displacement/Barrier %
100/100 50/50 0/100 100/0
good Forth -0.2 0.3 -0.3 -0.2
moderate Forth -12.3 -7.4 -9.8 -0.9
poor Forth -19.3 -12.0 -20.2 -2.1

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