Goose management policy in Scotland: 2010 review

14 Appendix E: National goose monitoring schemes and species surveys

Goose and Swan Monitoring Programme

The WWT/ JNCC/ SNH Goose and Swan Monitoring Programme ( GSMP) monitors the numbers of non-breeding geese and swans in the UK by forming an umbrella under which a range of species-specific surveys are carried out in a coordinated manner, some on an annual basis and the rest on ca a 5-year to 10-year cycle. Much of this work is carried out by a network of volunteers but some is carried out by professional staff.

Population estimates are generated on an annual basis for the following species: Svalbard Barnacle; Greenland White-fronted Goose; Icelandic Greylag Goose; and Icelandic Pink-footed Goose. Less regular updates on population estimates are available for the Greenland Barnacle Goose (5-year), Canada Goose (>10 year), Native Greylag Goose (>10 year) and Naturalised Greylag Goose (>10 year). In addition, sample surveys on age ratios and brood sizes in flocks are carried out for the majority of goose species (see www.wwt.org.uk/our-work/research/waterbird-monitoring/goose-swan-monitoring).

Wetland Bird Survey

The BTO/ RSPB/ JNCC Wetland Bird Survey ( WeBS) in association with WWT is the main scheme for monitoring non-breeding waterbirds in the UK, and includes geese, swans, ducks and waders. Annually around 3,000 volunteers participate in WEBS, which involves synchronised monthly counts of all waterbirds at a range of wetlands (e.g. lochs, ponds, marshes, canals, sections of open coast and all the main estuaries hosting concentrations of waterfowl). The 'core count' period extends from September to March. Additional information is also collected for geese, which tend to disperse to feed on agricultural land during the day necessitating counted at dusk or dawn at the roost sites. Collated data are available from 1947 and include the historical surveys of the WWT National Wildfowl Counts ( NWC) and the BTO Birds of Estuaries Enquiry ( BoEE).

Annual indices and trends at the UK level are derived from WeBS data for all goose species, apart from Greenland Barnacle, the NW Scotland (Native) Greylag, Taiga Bean, Lesser White-fronted Goose and the naturalised goose species (apart from Canada goose for which there is sufficient data). To generate these trends, population data for a number of species are derived from the national goose surveys co-ordinated by WWT as part of the GSMP (for e.g. Icelandic Pink-footed and Icelandic Greylag Goose (October to December); Native Greylag ( NW Scotland, August and February); East Canadian High Arctic Light-bellied Brent (October); and Svalbard Barnacle Goose (October to March). Additional data are also provided for Greenland White-fronted Goose (co-ordinated by the Greenland White-fronted Goose Study Group and the National Parks and Wildlife Service, Ireland) and for the Taiga Bean Goose (as organized by the Bean Goose Action Group).The most recent published estimates are based on information up to and including 2008/2009 (Calbrade et al. 2010).

WeBS data has recently been used to update the 1% thresholds for the designation of sites of national and internal importance for waterfowl species Table E1 ). These are not used by JNCC in terms of designation of potential SPAs however.

Table E1. Revised 1% thresholds for national and international importance for Scottish wintering goose populations (taken from Calbrade et al. 2010)

Species	WEBS (based on Kershaw and Cranswick 2003)	WEBS (based on Kershaw and Cranswick 2003)	JNCC (based on Rose and Scott 1997)
	GB	International	GB
Taiga Bean Goose	4*	800	50
Pink-footed Goose	2,400	2,700	1,900
Greenland White-fronted Goose	209	270	140
Icelandic Greylag Goose	819	870	1000
Native Greylag Goose	90	100	-
Greenland Barnacle Goose	450	560	270
Svalbard Barnacle Goose	220	270	120
Svalbard Light-bellied Brent Goose	30*	-	70

* 50 is the minimum qualifying level for national importance

WeBS data feed into the BTO conservation alerts system, a standardised programme that monitors changes in the numbers of wintering waterbirds and fkags up changes that may be adverse and significant on an annual basis. Trends are generated for the short, medium and long term (5, 10 and 15 years respectively) for the UK and individual country level. The most recent update incorporates data up to and including the winter of 2004/2005 (Maclean and Austin 2007). For Scotland, data were sufficient for 35 species, including only the Svalbard Light-bellied Brent Goose. At the UK scale, data are sufficient for 39 species, of which three are geese: European White-fronted Goose, Dark-bellied Brent Goose and Svalbard Light-bellied Brent Goose.

International Waterbird Census

The International Waterbird Census, which is co-ordinated by Wetlands International, covers 100 countries across five continents and is the most extensive waterbird census in the world. The resulting information is then published in 'Waterbird Estimates' by Wetlands International and AEWA, along with data derived from atlas projects, one surveys off surveys and any other relevant information taken from peer reviewed papers and unpublished reports. Collectively these provide estimates and trends of waterbird populations throughout the world. Moreover they underpin wetland conservation policy at an international level by identifying sites that hold 1% or more of a waterbird populations, thus qualifying as Wetlands of International Importance under the Ramsar Convention.

Single species surveys

Svalbard Barnacle Goose

Data on the numbers and age structure of the wintering Svalbard population have been collected on an annual basis since 1957 and 1959 respectively on the Solway by WWT. Weekly counts of flocks are undertaken during in the arrival and departure period of October and April/May respectively. Outside these periods, counts are carried out fortnightly (Griffin 2009). These counts are carried out separately to those carried out under the Solway Goose Management Scheme.

Greenland Barnacle

A total of twelve international surveys has been conducted for the populations of Greenland Barnacle Goose wintering in Scotland and Ireland between 1959 and 2008, coordinated by WWT. Surveys are carried out using a combination of aerial and ground counts on a single visit in March. In addition, there have been intermittent annual studies since the 1950s on Islay, Coll, Tiree, North Uist and its surrounding isles, South Walls and the North Sutherland coast. Information on age ratios and brood size has been collected systematically on Islay dating back to the 1960s, with data collected only sporadically elsewhere.

Greenland White-fronted Goose

International counts have carried out annually since the winter of 1982/1983 as a joint effort between Great Britain (Greenland White-fronted Goose Study Group) and Ireland (National Parks and Wildlife Service) to survey the global population of wintering Greenland White-fronted goose (excluding Norway). A minimum of two counts (autumn and spring) are carried out. In addition, there are over twenty sites where population counts are collected monthly from September to March (although the frequency of these counts varies from one to site to another). Age assessments are also collated for a number of sites (e.g. in 2008/2009 data were collected at 22 sites in Scotland and Ireland; Fox et al. 2009).

Icelandic Greylag Goose

Counts of wintering Icelandic Greylag Geese have been undertaken annually as part of the Icelandic-breeding Goose Census ( IGC) since 1960. Additional population counts are also available from 1957. The IGC covers Scotland, England and Ireland and accepts additional data from the Faroe Islands, Norway and Iceland. Counts are carried out once a month in October, November and December at roost sites (usually at dawn) or of feeding birds (where information on the location of the roost sites is poor). The timing of the core monthly counts has been adjusted to allow for the later departure of Icelandic Greylag Geese from their wintering grounds that has occurred recently. Additional information on the proportion of young and breeding success is also collected from a sub sample of sites throughout Scotland.

Until relatively recently there was little concern that there was overlap in the ranges of wintering Icelandic and resident populations of Greylag Geese. However since 2000 it has become clear that the wintering range of the Icelandic geese overlaps with that of the resident population on Orkney. Therefore it is important to survey the resident Greylag Geese in autumn prior to the arrival of the Icelandic population in order to be able to provide a reliable estimate of the size of the Icelandic population. To date this has only been possible when the 2008/2009 Scottish Greylag Goose Survey was carried out.

Native Greylag Goose

Complete censuses of the native Greylag population have been carried out on only two occasions: (i) the 1997 survey of Northwest Scotland Greylag Geese organised by WWT; and (II) the 2008/2009 Scottish Greylag Goose Survey in Scotland organised by WWT, which covered both the native and the naturalised population. For the 1997 survey, counts were carried out during the post moult period in the last two weeks of August, when birds tend to concentrated in agricultural fields. The latter 2008/2009 survey had two survey periods designed around the detection probabilities of the two different breeding populations of Greylag Geese. The first survey period was in late June and early June (which targeted the moult period of geese breeding south and east of the Great Glen, the area associated with the naturalised/re-established population). The second was in the last few weeks of August and was carried out in areas north and west of the Great Glen (the traditional areas of the native population). More regular population counts along with productivity estimates and the collation of ringing and resighting data are collected in three areas only: the Uists; Tiree and Coll; and Sutherland.

Naturalised Greylag Goose

To date there have been two complete censuses (across the whole of the UK) of naturalised Greylag Geese, both organised by WWT: (i) The 1991 Survey of Introduced Geese; and (ii) The Naturalised Goose Survey 2000. These involved single counts at the moult sites during the months of June and July. There was lack of coverage in Shetland, Central Region and parts of the Highland Region for the 1991 survey however.

In addition, there have been two Scottish censuses of the naturalised Greylag Goose population: (i) The 1991 survey of re-established Greylag Geese in Scotland, organised by the SOC; and (ii) The 2008/2009 survey of Greylag Geese in Scotland, organised by WWT. The 1991 Scottish survey combined a questionnaire-type approach by region sent out to recorders and collation of information from local bird records as a means of assessing the population size at this time. The more recent survey of 2008/2009 was designed to survey the combined summering range of Native and naturalised Greylag Geese (see under Native Greylag for further details).

Icelandic Pink-footed Goose

Complete population censuses of wintering Pink-footed Geese have been undertaken annually as part of the Icelandic-breeding Goose Census ( IGC), starting in 1960. Additional information is also available from the 1950s. The IGC covers Scotland, England, Ireland and accepts additional data from the Faroe Islands, Norway and Iceland. Pink-footed Geese are counted once a month in October and November at their roost sites, with a few additional counts of feeding birds as well. Additional information on the proportion of young and breeding success is also collected from a sub sample of sites throughout Scotland and England.

Taiga Bean Goose

Wintering Taiga Bean Geese are restricted primarily to one site in Scotland, the Slammanan Plateau, Falkirk. To date monitoring has been carried out annually, since the mid 1980s, by the Bean Goose Action Group as part of the LBAP process for both Falkirk and North Lanarkshire. Survey effort has varied on an annual basis in terms of frequency and coverage (Maciver 2009). It has been suggested that the recent level of monitoring may generate an excess of information and could also possibly be intrusive (Mitchell 2010). Age assessments have not been carried out routinely at Slammanan to date. The monitoring of Bean Goose on the Slammanan Plateau has recently been reviewed (Mitchell 2010). An average of 76 field visits between late September and early March and 33 roost sites counts had taken place between 1997/1998 and 2008/2009. Recommendations for future monitoring included twice weekly field counts in October and in the first half of November followed by a weekly count until the end of February (checking fields along standardised routes). In addition it was also proposed that roost counts should be carried out on a monthly basis from October to February and that, wherever possible, information on the proportion of young should also be collected.

Canada Goose

Complete censuses of Canada Geese have been carried out in 1953, 1967, 1975, 1991 and 2000. The most recent survey was carried out as part of the Naturalised Goose Survey of 2000 (Rowell et al. 2004). Counts are carried out at moult sites in late June and early July and are co-ordinated by WWT with help from WeBS volunteers. Information is also collated on the proportion of young at all sites.

East Atlantic Light-bellied Brent Goose

Within the UK, the population of the East Atlantic Light-bellied Brent Goose is currently monitored through WeBS. Population estimates are available from 1959.

Canadian High Arctic Light-bellied Brent Goose

Within the UK, the population of the Canadian High Arctic Light-bellied Brent Goose is currently monitored by the Irish Brent Goose Research Group (Ireland) and through WeBS.

Naturalised Snow Goose and Bar-headed Goose

To date there have been complete censuses of these naturalised geese: (i) The 1991 Survey of Introduced Geese; and (ii) The Naturalised Goose Survey 2000; both organised by WWT. There was lack of coverage in Shetland, Central Region and parts of the Highland Region in the 1991 survey, so numbers reported then could represent an underestimate.