2.7.3 Herring gull

Table 2.11: Demographic rates for the guillemot PVA models

SPA		Survivals						Productivity
		S0->1	S1->2	S2->3	S3->4	S4->5	SA	PA
Forth Islands	Mean	0.777	0.878	0.878	0.878	0.878	0.878	0.978
Forth Islands	SD	0.092	0.034	0.034	0.034	0.034	0.034	0.307
Farne Islands	Mean	0.777	0.878	0.878	0.878	0.878	0.878	0.978
	SD	0.092	0.034	0.034	0.034	0.034	0.034	0.307
St Abb's Head to Fast Castle	Mean	0.777	0.878	0.878	0.878	0.878	0.878	0.978
	SD	0.092	0.034	0.034	0.034	0.034	0.034	0.307
Fowlsheugh	Mean	0.777	0.878	0.878	0.878	0.878	0.878	0.978
Fowlsheugh	SD	0.092	0.034	0.034	0.034	0.034	0.034	0.307
Eggs/pair: 3 (Snow and Perrins, 1998)
Age at first breeding: 5 (Horswill and Robinson, 2015)

Table 2.12: References and comments on demographic rates specified for Herring Gull PVA models. 'SE' and 'SD' refer to standard error and standard deviation, respectively; “H&R” refers to Horswill and Robinson (2015)

SPA	Demographic parameter	Source	Comments
Forth Islands	PA	SMP (2022)	Annual breeding success data from Isle of May (1989 - 2007).
	S0->1	Chabrzyk and Coulson (1976)	Isle of May immature survival estimates (time-series: 1966 - 1968).
	S1->2, …, SA	Wanless et al. (1996)	Isle of May adult survival estimates (time-series: 1989 - 1992).
Farne Islands	PA	SMP (2022)	Used the same parameter values as Herring Gull in Forth Islands. No breeding success data available on the SMP database for Farne Islands. H&R provides productivity estimates for Farne Islands, but the study reference points to an analysis on Canna .
	S0->1	Chabrzyk and Coulson (1976)	SPA-specific survival estimates not available. Used the same parameter values as Herring Gull in Forth Islands.
	S1->2, …, SA	Wanless et al. (1996)
St Abb’s Head to Fast Castle	PA	SMP (2022)	SPA-specific estimates not available. Used the same parameter values as Herring Gull in Forth Islands.
	S0->1	Chabrzyk and Coulson (1976)	SPA-specific survival estimates not available. Used the same parameter values as Herring Gull in Forth Islands.
	S1->2, …, SA	Wanless et al. (1996)
Fowlsheugh	PA	SMP (2022)	Used the same parameter values as Herring Gull in Forth Islands. SPA-specific breeding success data available on SMP database, but for a very short time-series (2013-2016) and therefore likely to misrepresent inter-annual variability in colony. Preference given to longer time-series from the Isle of May.
	S0->1	Chabrzyk and Coulson (1976)	SPA-specific survival estimates not available. Used the same parameter values as Herring Gull in Forth Islands.
	S1->2, …, SA	Wanless et al. (1996)

2.7.4 Kittiwake

Table 2.13: Demographic rates for kittiwake PVA models

SPA		Survivals					Productivity
SPA		S0->1	S1->2	S2->3	S3->4	SA	PA
Forth Islands	Mean	0.79	0.855	0.855	0.855	0.855	0.674
Forth Islands	SD	0	0.067	0.067	0.067	0.067	0.357
Farne Islands	Mean	0.79	0.855	0.855	0.855	0.855	0.824
Farne Islands	SD	0	0.067	0.067	0.067	0.067	0.316
Flamborough and Filey Coast	Mean	0.79	0.854	0.854	0.854	0.854	0.855
Flamborough and Filey Coast	SD	0	0.077	0.077	0.077	0.077	0.331
Coquet Island	Mean	0.79	0.855	0.855	0.855	0.855	1.121
Coquet Island	SD	0	0.067	0.067	0.067	0.067	0.277
St Abb's Head to Fast Castle	Mean	0.79	0.855	0.855	0.855	0.855	0.667
St Abb's Head to Fast Castle	SD	0	0.067	0.067	0.067	0.067	0.334
Fowlsheugh	Mean	0.79	0.855	0.855	0.855	0.855	0.813
Fowlsheugh	SD	0	0.067	0.067	0.067	0.067	0.336
Buchan Ness to Collieston Coast	Mean	0.79	0.855	0.855	0.855	0.855	0.632
Buchan Ness to Collieston Coast	SD	0	0.067	0.067	0.067	0.067	0.333
Troup, Pennan and Lion's Heads	Mean	0.79	0.855	0.855	0.855	0.855	1.068
Troup, Pennan and Lion's Heads	SD	0	0.067	0.067	0.067	0.067	0.228
East Caithness Cliffs	Mean	0.79	0.854	0.854	0.854	0.854	1.043
East Caithness Cliffs	SD	0	0.077	0.077	0.077	0.077	0.41
North Caithness Cliffs	Mean	0.79	0.854	0.854	0.854	0.854	0.89
North Caithness Cliffs	SD	0	0.077	0.077	0.077	0.077	0.412
West Westray	Mean	0.79	0.812	0.812	0.812	0.812	0.537
West Westray	SD	0	0.131	0.131	0.131	0.131	0.468
Eggs/pair: 2 (Snow and Perrins, 1998)
Age at first breeding: 4 (Horswill and Robinson, 2015)

Table 2.14: References and comments on demographic rates specified for Kittiwake PVA models. 'SE' and 'SD' refer to standard error and standard deviation, respectively; “H&R” refers to Horswill and Robinson (2015)

SPA	Demographic parameter	Source	Comments
Forth Islands	PA	CEH (2018)	Annual breeding success data from Isle of May (2007 - 2016).
	S0->1	Horswill and Robinson (2015)	SPA-specific survival estimates not available. National-level figure used (with SD fixed over time).
	S1->2, …, SA	Jitlal et al. (2017)	Isle of May colony adult survival estimates (updated from Frederiksen et al 2004 - time-series: 1986 - 2002).
Farne Islands	PA	SMP (2022)	Annual breeding success data from Farne Islands (1987 - 2015).
	S0->1	Horswill and Robinson (2015)	SPA-specific survival estimates not available. Adopted the same parameters as Kittiwake in Forth Islands.
	S1->2, …, SA	Jitlal et al. (2017)
Flamborough and Filey Coast	PA	SMP (2022)	Annual breeding success data from Flamborough Head and Bempton Cliffs (1986 - 2019).
	S0->1	Horswill and Robinson (2015)	SPA-specific survival estimates not available. Adopted the same parameters as Kittiwake in Forth Islands.
	S1->2, …, SA	Jitlal et al. (2017)
Coquet Island	PA	SMP (2022)	Annual breeding success data from Coquet Island RSPB (1993 - 2019).
	S0->1	Horswill and Robinson (2015)	SPA-specific survival estimates not available. Adopted the same parameters as Kittiwake in Forth Islands.
	S1->2, …, SA	Jitlal et al. (2017)
St Abb’s Head to Fast Castle	PA	SMP (2022)	Annual breeding success data from St Abb’s Head NNR (1987 - 2019).
	S0->1	Horswill and Robinson (2015)	SPA-specific survival estimates not available. Adopted the same parameters as Kittiwake in Forth Islands.
	S1->2, …, SA	Jitlal et al. (2017)
Fowlsheugh	PA	SMP (2022)	Annual breeding success data from Fowlsheugh RSPB (1986 - 2021).
	S0->1	Horswill and Robinson (2015)	SPA-specific survival estimates not available. Adopted the same parameters as Kittiwake in Forth Islands.
	S1->2, …, SA	Jitlal et al. (2017)
Buchan Ness to Collieston Coast	PA	SMP (2022)	Annual breeding success data from Buchan Ness to Collieston (1989 - 2019).
	S0->1	Horswill and Robinson (2015)	SPA-specific survival estimates not available. Adopted the same parameters as Kittiwake in Forth Islands.
	S1->2, …, SA	Jitlal et al. (2017)
Troup, Pennan and Lion’s Heads	PA	SMP (2022)	Annual breeding success data from Troup & Lion’s Head RSPB (Coast & Reserve) (2011 - 2019).
	S0->1	Horswill and Robinson (2015)	SPA-specific survival estimates not available. Adopted the same parameters as Kittiwake in Forth Islands.
	S1->2, …, SA	Jitlal et al. (2017)
East Caithness Cliffs	PA	SMP (2022)	Annual breeding success data from Ires Geo, Rockhead, Creag na Cuinge 1 & Inver Hill (1986 - 1993; 2013). IMPORTANT NOTE: there is a 20-year gap in the time series, with the 2013 estimate being substantially lower than the average in earlier years. For now, assuming 2013 estimates are accurate and expressing breeding volatility in the region.
	S0->1	Horswill and Robinson (2015)	SPA-specific survival estimates not available. National-level figure used (with SD fixed over time).
	S1->2, …, SA	Mobbs et al. (2020)	SPA-specific survival estimates not available. National level figures used.
North Caithness Cliffs	PA	SMP (2022)	Annual breeding success data from Skirza Head & Sandside Head 1 (1986 - 1993; 2013). IMPORTANT NOTE: there is a 20-year gap in the time series, with the 2013 estimate being 0. For now, assuming 2013 figure is accurate and expressing breeding volatility in the region.!
	S0->1	Horswill and Robinson (2015)	SPA-specific survival estimates not available. National-level figure used (with SD fixed over time).
	S1->2, …, SA	Mobbs et al. (2020)	SPA-specific survival estimates not available. National level figures used.
West Westray	PA	SMP (2022)	Annual breeding success data from West Westray SPA (2010 - 2021).
	S0->1	Horswill and Robinson (2015)	SPA-specific survival estimates not available. National-level figure used (with SD fixed over time).
	S1->2, …, SA	Oro and Furness (2002)	SPA-specific survival estimates not available - Foula Island (Shetland) adult survival estimates adopted (time-series: 1987 - 1997).

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