# 4 Conclusions

- Below, we summarise the worst case, in terms of reduction in population growth rate and median population size for each species for the expected life-span of the project (25 years). In all cases, modelling of Scoping Approach mortality estimates resulted in greatest effects for project alone and in-combination. It is important to note that density dependent effects on growth rate are not included in these models.
- For gannet, project alone impacts were greatest at Forth Islands SPA for Scoping Approach B at the end of 35 years of impact (2062) resulting in a 4.3% and 0.1% reduction in population growth rate and median population size, respectively. With regards incombination impacts, the North Sea consented Scoping B was the worst case for the Flamborough and Filey Coast SPA resulting in a 39% and 14% reduction in population growth rate and median population size, respectively
- For guillemot, project alone impacts were greatest at St Abb’s Head to Fast Castle SPA for Scoping Approach B at the end of 35 years of impact (2062) resulting in a 33% and 11% reduction in population growth rate and median population size, respectively. With regards incombination impacts on this SPA, the North Sea consented Scoping B was the worst case for resulting in a 38% and 13% reduction in population growth rate and median population size, respectively. The incombination totals compares with the equivalent Developer Approach scenario of 8.6% and 0.02% reduction in population growth rate and median population size, respectively.
- For herring gull, project alone impacts were greatest at St Abb’s Head to Fast Castle SPA for Scoping Approach at the end of 35 years of impact (2062) resulting in a 2.9% and 0.01% reduction in population growth rate and median population size, respectively. With regards incombination impacts on this SPA, the North Sea consented Scoping was the worst case resulting in a 5.3% and 0.01% reduction in population growth rate and median population size, respectively.
- For kittiwake, project alone impacts were greatest at St Abb’s Head to Fast Castle SPA for Scoping Approach B at the end of 35 years of impact (2062) resulting in a 62.5% and 2.7% reduction in population growth rate and median population size, respectively. With regards incombination impacts on this SPA, the North Sea consented Scoping B was the worst case for resulting in a 65.9% and 29.9% reduction in population growth rate and median population size, respectively. The incombination totals compares with the equivalent Developer Approach scenario of 52.1% and 2% reduction in population growth rate and median population size, respectively.
- For lesser black-back gull, project alone impacts were greatest at Forth Islands SPA for Scoping Approach at the end of 35 years of impact (2062) resulting in a 1.8% and 0.01% reduction in population growth rate and median population size, respectively.
- For puffin, project alone impacts were greatest at Forth Islands SPA for Scoping Approach B at the end of 35 years of impact (2062) resulting in a 1.4% reduction in population growth rate but no change in median population size, respectively. With regards incombination impacts on this SPA, the North Sea consented Scoping B was the worst case for resulting in a 12% and 0.04% reduction in population growth rate and median population size, respectively.
- For razorbill, project alone impacts were greatest at St Abb’s Head to Fast Castle SPA for Scoping Approach B at the end of 35 years of impact (2062) resulting in a 14.1% reduction in population growth rate and 0.04% reduction in median population size. With regards incombination impacts on this SPA, the North Sea consented Scoping B was the worst case for resulting in a 20.6% and 0.06% reduction in population growth rate and median population size, respectively.

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