East Anglia ONE Offshore Windfarm
April, 2016
28.
Thus, on the basis of the baseline surveys and the power analysis conducted here, a nonbreeding survey with a focus on October and November (2 surveys per month) and single surveys per month in December to March (a total of 8 surveys per winter) will obtain sufficient data to detect displacement of the species of primary concern at East Anglia ONE.
29.
The buffer distance analysis, comparing gannet densities around the wind farm under the assumption that most birds will be displaced with densities obtained around randomly relocated wind farms indicated that this methodology will be expected to identify the distance (to at least the nearest 500m) over which gannets may avoid the wind farm (macro-avoidance). While this was simulated using 500m increments, it may be possible to refine this to narrower distances to obtain a more precise estimate. Furthermore, this approach can also be applied at the scale of individual turbines to estimate within wind farm avoidance of turbines, for those species such as guillemot which are expected to continue to enter the wind farm.
4.2 Proposed survey design 30.
In presenting the results of the power analysis and the proposed survey design this report addresses the requirements set out by the MMO (letter dated 18th December 2015), listed in section 1 of this document.
31.
The power analysis indicated that using a targeted design, with more surveys during periods of peak activity, it will be possible to detect local declines in abundance post-construction in gannet (50% displacement), kittiwake (50%) and guillemot (30%). Consideration of the recorded densities of each of these species in April suggests that surveying in this month is likely to yield little in the way of useful data for gannet or kittiwake (neither species was recorded in the baseline surveys in April) with guillemot also present in much reduced numbers.
32. The proposed survey design is therefore:
Digital aerial surveys giving a coverage of around 17% of the study area; Conducted across eight surveys per winter (2 in each of October and November, 1 in each month December to March); An example of a suitable survey design (as illustrated in Figure 1) indicates this can be achieved with approximately 28 transects, 250m wide, separated by 1.4km (total coverage c. 17%), oriented across turbine rows (bearing c. 81°; NB, this orientation was selected to balance the objective of an east-west direction whilst also ensuring transects crossed turbine rows).
33.
Similar transect designs would also be expected to be suitable, however the timing of surveys and percentage coverage achieved should be no less than that detailed above.
Page 16
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35
