Population changes of breeding waders on farmland in relation to agri-environment management

Figures & data

Table 1. Agri-environment management options for farmland waders.

Scheme	Years available	Option description	Type for analysis	No. fields
ESA	1993–2000	Water margin grazing control	Grassland	20
ESA	1993–2000	Wetland grazing control	Wetland	3
CPS	1997–2000	Flood plain management	Wetland	8
CPS	1997–2000	‘Grassland for birds’ management	Grassland	27
CPS	1997–2000	Wetland creation and management	Wetland	6
RSS	2001–2006	Flood plain management	Wetland	3
RSS	2001–2006	Grazed grassland for birds	Grassland	38
RSS	2001–2006	Mown grassland for birds	Grassland	36
RSS	2001–2006	Wet grassland for waders	Wetland	36
RSS	2001–2006	Wetland creation and management	Wetland	4
ESA, Environmentally Sensitive Area; CPS, Countryside Premium Scheme; RSS, Rural Stewardship Scheme.

Figure 1. The distribution of sites surveyed for breeding waders in Scotland in 1992 and 2005. Filled squares indicate sites with agri-environment management agreements for breeding waders under one or more options listed in Table 1; open squares indicate sites not under agri-environment management.

Figure 2. Modelled estimates (± se) of numbers of breeding pairs of each wader species on sites with (A) and without (C) agri-environment scheme (AES) management. Numbers refer to years: 1992 (92) and 2005 (05); species for which the change in numbers between 1992 and 2005 differed significantly between AES and Control sites are indicated by asterisks (**P < 0.01; ***P < 0.001).

Table 2. The number of fields in each of the main agri-environment scheme (AES) management categories (grassland and wetland), together with the number within which a breeding territory of each wader species was recorded in at least one of the survey years.

Type	OC	L	SN	CU	RK	Total fields
Grassland	36	29	7	36	9	72
Wetland	30	21	6	24	15	43
Non-AES	445	322	106	304	113	1015
OC, Oystercatcher; L, Lapwing; SN, Snipe; CU, Curlew; RK, Redshank.

Figure 3. Modelled estimates (± se) of numbers of breeding pairs of each wader species on individual fields under ‘grassland’ agri-environment scheme (AES) management (G), ‘wetland’ AES management (W), and not under AES management (C) in 1992 (92) and 2005 (05). Species for which the change in numbers between 1992 and 2005 differs significantly between ‘grassland’, ‘wetland’ and control fields are indicated by asterisks (*P < 0.05; ** P < 0.01; *** P < 0.001).

Figure 4. Relationship between annual population growth under agri-environment scheme management and the proportion of the overall population that must benefit from this management in order to achieve overall population stability. Example plotted is for Lapwings with an assumed constant rate of decline of 2.4% per annum, amounting to 27% over 13 years.