2023 census dates

for the Icelandic-breeding Goose Census:

14–15 October
18–19 November

Goose and Swan Monitoring Programme Logo

Project partners

British Trust for Ornithology logo
JNCC logo
NatureScot Logo

Project partners

British Trust for Ornithology logo
JNCC logo

Taking part in GSMP

The GSMP monitors the numbers and distribution of wintering goose and swan populations, as well as breeding success. There are various volunteer surveys to take part in, all of which contribute valuable data to our understanding of the sites which support internationally important populations of geese and swans, and of the birds' distribution, demography and breeding success. 
Counting geese. Teresa Frost
Counting geese. Teresa Frost 

Monitoring population size and distribution

There are a variety of GSMP surveys that are designed to monitor the size and distribution of the UK’s swan and goose populations; some are undertaken annually, whilst others are carried out periodically.

These surveys require varying levels of expertise, but for the most part, you will need to be confident in your identification of the relevant goose or swan species for the census that you are carrying out. You will also need to have some experience in counting birds, and be confident in your ability to estimate potentially large numbers of birds accurately.

Monitoring breeding success

The annual reproductive success of each of the UK’s migratory swan and native goose populations is assessed through the GSMP, and involves observers recording the number of young birds present amongst flocks. In addition to experience in counting and recording large numbers of birds, you also need to be confident identifying first-winter birds to take part in surveys involving age assessments.

How to get involved

If you are interested in becoming a GSMP volunteer, please contact the GSMP office at gsmp [at] bto.org. You can also contact the GSMP Organiser for more information about taking part in the GSMP. 

Icelandic-Breeding Goose Census (IGC)

To find and request to count vacant IGC sites, you can use our interactive map.

Age Assessments

Age Assessments can be carried out on any site, to take part please sign up to GSMP Online via the homepage.

For other GSMP surveys, see the Guide to the Surveys below.


Health and Safety

BTO provides Health and Safety information for volunteers, which we recommend you read before starting your surveys.

Guide to the surveys

A comprehensive overview of each GSMP survey, including methodology and how to get involved. 

Recording forms

Recording forms are available to download for the following surveys:

  • Icelandic-breeding Goose Census (IGC)

Two coordinated IGC counts are made in autumn: sites supporting Pink-footed Geese are surveyed during October and November, whilst those supporting Greylag Geese are counted in November. At sites where both species occur, counts take place in both months. 

  • National goose and swan age assessments

These assessments aim to record the age and brood size of all wintering swan and goose species, where age can be determined in the field.

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