2.7.5 Lesser black-backed gull

Table 2.15: Demographic rates for the Lesser Black-backed Gull PVA models

SPA		Survivals						Productivity
SPA		S0->1	S1->2	S2->3	S3->4	S4->5	SA	PA
Forth Islands	Mean	0.820	0.913	0.913	0.913	0.913	0.913	0.846
Forth Islands	SD	0.000	0.022	0.022	0.022	0.022	0.022	0.303
Farne Islands	Mean	0.820	0.913	0.913	0.913	0.913	0.913	0.846
Farne Islands	SD	0.000	0.022	0.022	0.022	0.022	0.022	0.303
Coquet Island	Mean	0.820	0.913	0.913	0.913	0.913	0.913	0.358
Coquet Island	SD	0.000	0.022	0.022	0.022	0.022	0.022	0.527
Eggs/pair: 3 (Snow and Perrins, 1998)
Age at first breeding: 5 (Horswill and Robinson, 2015)

Table 2.16: References and comments on demographic rates specified for Lesser Black-backed 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	Harris (1970)	SPA-specific survival estimates not available. Used Mean based on data from Skomer, Skokholm and Grassholm Islands (Wales, time-series: 1968 - 1969) as per H&R. Furthermore, no SD estimate available for s0_1, thus assumed fixed over time (i.e., SD = 0).
	S1->2, …, SA	Wanless et al. (1996)	Isle of May adult survival estimates (time-series: 1989 - 1992).
Farne Islands	PA	SMP (2022)	SPA-specific estimates not available. Used the same parameter values as Lesser Black-backed Gull in Forth Islands.
	S0->1	Harris (1970)	SPA-specific survival estimates not available. Adopted the same parameter values as Lesser Black-backed Gull in Forth Islands.
	S1->2, …, SA	Wanless et al. (1996)
Coquet Island	PA	SMP (2022)	Annual breeding success data from Coquet Island RSPB (2008 - 2019). Extremely small colony, with annual breeding success estimates based on low number of AOT counts (<30 per year). Still, estimates considered to be representative of the level and variability of annual productivity in the colony.
	S0->1	Harris (1970)	SPA-specific survival estimates not available. Adopted the same parameter values as Lesser Black-backed Gull in Forth Islands.
	S1->2, …, SA	Wanless et al. (1996)

2.7.6 Puffin

Table 2.17: Demographic rates for the puffin PVA models

SPA		Survivals												Productivity
			S0->1		S1->2		S2->3		S3->4		S4->5		SA		PA
Forth Islands	Mean	0.892		0.892		0.892		0.76		0.805		0.901		0.648
Forth Islands	SD	0.046		0.046		0.046		0.093		0.083		0.091		0.157
Farne Islands	Mean	0.892		0.892		0.892		0.76		0.805		0.901		0.77
Farne Islands	SD	0.046		0.046		0.046		0.093		0.083		0.091		0.176
North Caithness Cliffs	Mean	0.892		0.892		0.892		0.76		0.805		0.915		0.415
North Caithness Cliffs	SD	0.046		0.046		0.046		0.093		0.083		0.11		0.212
Eggs/pair: 1 (Snow and Perrins, 1998)
Age at first breeding: 5 (Horswill and Robinson, 2015)

Table 2.18: References and comments on demographic rates specified for Puffin PVA models. 'SE' and 'SD' refer to standard error and standard deviation, respectively; “H&R” refers to Horswill and Robinson (2015)

SPA		Source	Comments
Forth Islands	PA	CEH (2018)	Annual breeding success data from Isle of May (2007 - 2016). Historically low productivity in 2007 attributed to difficult feeding conditions and severe weather. Despite being extreme, observation was deemed accurate and thus included in the calculations.
	S0->1, …, S2->3	Horswill and Robinson (2015)	SPA-specific survival estimates not available. Adopted estimates from colonies in New Brewick, Canada, as suggested by H&R. Following the original study (Breton et al., 2006), H&R provides a single mean (0.709) and SE (0.022, converted to SD = 0.108) for the first 3 age-classes. Corresponding annual mean rate computed as 0.709(1/3) = 0.892. Approximate annual SD (0.048) derived from 1000 draws from a beta distribution with mean = 0.709 and SD = 0.108
	S3->4, …, S4->5	Horswill and Robinson (2015)	SEs reported in H&R converted to SDs to express inter-annual variability, following the same approach as Mobbs et al. (2020).
	S->A	Lahoz-Monfort et al. (2011)	Isle of May adult survival estimates.
Farne Islands	PA	SMP (2022)	Annual breeding success data from Farne Islands (1994 - 2015).
	S0->1, …, S2->3	Horswill and Robinson (2015)	SPA-specific survival estimates not available. Adopted the same parameter values as Puffin in Forth Islands
	S3->4, …, S4->5	Horswill and Robinson (2015)
	S->A	Lahoz-Monfort et al. (2011)
	S3->4, …, S4->5	Horswill and Robinson (2015)
	S->A	Lahoz-Monfort et al. (2011)
	S3->4, …, S4->5	Horswill and Robinson (2015)
	S->A	Lahoz-Monfort et al. (2011)
North Caithness Cliffs	PA	Cook and Robinson (2010)	SPA-specific estimates not available. Adopted figures based on data gathered from NW Scotland (Orkney and Shetland), as provided by the NEPVA Tool (Mobbs et al., 2020)
	S0->1, …, S4->5	Horswill and Robinson (2015)	SPA-specific survival estimates not available. Adopted the same parameter values as Puffin in Forth Islands
	S->A	Harris et al. (2005)	SPA-specific survival estimates not available. Parameters based on estimates from the Fair Isle colony (Shetland, time-series: 1990 - 2002)

2.7.7 Razorbill

SPA		Survivals						Productivity
		S0->1	S1->2	S2->3	S3->4	S4->5	SA	PA
Forth Islands	Mean	0.794	0.794	0.910	0.910	0.910	0.910	0.564
Forth Islands	SD	0.134	0.134	0.058	0.058	0.058	0.058	0.070
Farne Islands	Mean	0.794	0.794	0.910	0.910	0.910	0.910	0.679
Farne Islands	SD	0.134	0.134	0.058	0.058	0.058	0.058	0.108
Flamborough and Filey Coast	Mean	0.794	0.794	0.910	0.910	0.910	0.910	0.630
Flamborough and Filey Coast	SD	0.134	0.134	0.058	0.058	0.058	0.058	0.074
St Abb's Head to Fast Castle	Mean	0.794	0.794	0.910	0.910	0.910	0.910	0.679
St Abb's Head to Fast Castle	SD	0.134	0.134	0.058	0.058	0.058	0.058	0.108
Fowlsheugh	Mean	0.794	0.794	0.910	0.910	0.910	0.910	0.459
Fowlsheugh	SD	0.134	0.134	0.058	0.058	0.058	0.058	0.236
Troup, Pennan and Lion's Heads	Mean	0.794	0.794	0.910	0.910	0.910	0.910	0.459
Troup, Pennan and Lion's Heads	SD	0.134	0.134	0.058	0.058	0.058	0.058	0.236
East Caithness Cliffs	Mean	0.794	0.794	0.910	0.910	0.910	0.910	0.459
East Caithness Cliffs	SD	0.134	0.134	0.058	0.058	0.058	0.058	0.236
Eggs/pair: 1 (Snow and Perrins, 1998)
Age at first breeding: 5 (Horswill and Robinson, 2015)

Table 2.19: Demographic rates for the razorbill PVA models

Table 2.20: References and comments on demographic rates specified for Razorbill PVA models. 'SE' and 'SD' refer to standard error and standard deviation, respectively; “H&R” refers to Horswill and Robinson (2015)

SPA		Source	Comments
Forth Islands	PA	CEH (2018)	Annual breeding success data from Isle of May (2007 - 2016).
	S0->1, S1->2	Horswill and Robinson (2015)	SPA-specific survival estimates not available. Using figures from colonies in Machias Seal Island and Gannet Islands, Canada, as suggested by H&R (time-series: 1995 - 2006). H&R provides a single mean (0.630) and SD (0.209) for the first 2 age-classes. Corresponding annual mean rate computed as 0.63(1/2) = 0.794. Approximate annual SD (0.134) derived from 1000 draws from a beta distribution with mean = 0.63 and SD = 0.209.
	S2->3, …, SA	Jitlal et al. (2017)	Isle of May adult survival estimates (based on Lahoz-Monfort et al (2011, 2014).
Farne Islands	PA	SMP (2022)	Annual breeding success data from Farne Islands (1996 - 2015).
	S0->1, S1->2	Horswill and Robinson (2015)	SPA-specific survival estimates not available. Adopted the same parameter values as Razorbill in Forth Islands
	S2->3, …, SA	Jitlal et al. (2017)
Flamborough and Filey Coast	PA	SMP (2022)	Annual breeding success data from Flamborough Head and Bempton Cliffs (2009 - 2019).
	S0->1, S1->2	Horswill and Robinson (2015)	SPA-specific survival estimates not available. Adopted the same parameter values as Razorbill in Forth Islands.
	S2->3, …, SA	Jitlal et al. (2017)
St Abb’s Head to Fast Castle	PA	SMP (2022)	Used the same parameter values as Razorbill in Farne Islands. SPA-specific breeding success data available on the SMP database, but for a very sparse time-series (1992, 2008 & 2014). Preference given to the longer time-series available from the neighbouring Farne Islands colony.
	S0->1, S1->2	Horswill and Robinson (2015)	SPA-specific survival estimates not available. Adopted the same parameter values as Razorbill in Forth Islands
	S2->3, …, SA	Jitlal et al. (2017)
Fowlsheugh	PA	Horswill and Robinson (2015)	SPA-specific estimates not available. Northern UK figures used.
	S0->1, S1->2	Horswill and Robinson (2015)	SPA-specific survival estimates not available. Adopted the same parameter values as Razorbill in Forth Islands
	S2->3, …, SA	Jitlal et al. (2017)
	S2->3, …, SA	Jitlal et al. (2017)
Troup, Pennan and Lion’s Heads	PA	Horswill and Robinson (2015)	SPA-specific estimates not available. Northern UK figures used instead
	S0->1, S1->2	Horswill and Robinson (2015)	SPA-specific survival estimates not available. Adopted the same parameter values as Razorbill in Forth Islands
	S2->3, …, SA	Jitlal et al. (2017)
East Caithness Cliffs	PA	Horswill and Robinson (2015)	SPA-specific estimates not available. Northern UK figures used instead
	S0->1, S1->2	Horswill and Robinson (2015)	SPA-specific survival estimates not available. Adopted the same parameter values as Razorbill in Forth Islands
	S2->3, …, SA	Jitlal et al. (2017)

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