Skip to Content

Resource hub

Census of grey seals (Halichoerus grypus) around the Southwest England Seal Monitoring Unit by aerial survey during August 2023 2025

Abstract

This report provides a census of grey seal populations around the Southwest England Seal Monitoring Unit (SMU), during August 2023.

For the majority (approximately 95%) of the UK, grey seal (Halichoerus grypus) population, abundance is monitored using a combination of pup production estimates and August haul out counts (surveyed during the harbour seal moult). Grey seals in the UK are part of a single metapopulation, exhibiting large scale inter-seasonal movements. As such, August counts provide the required indicator of the foraging distribution of grey seals.

This study demonstrates both the appropriateness of an aerial survey methodology to complete an SMU-wide aerial August census of grey seals, and also the added value of an integrated approach, combining aerial methods with citizen science ground count methods.

This report may not be fully accessible for all users. If you need a copy in a different or more accessible format, please contact Communications@jncc.gov.uk.

Resource type Publication

Topic category Environment

Reference date 2025·01·01

Citation
Thompson, D. 2024. Census of grey seals (Halichoerus grypus) around the Southwest England Seal Monitoring Unit by aerial survey during August 2023. JNCC Report 778 (Survey Report). JNCC, Aberdeen, ISSN 0963-8091.

Lineage
The surveys undertaken for this research were carried out as part of a collaborative study funded by JNCC, Natural Resources Wales, and the Natural Environment Research Council.

Responsible organisation
Communications, JNCC publisher

Limitations on public access No limitations

Use constraints Available under the Open Government Licence 3.0

Metadata date 2025·01·27

Metadata point of contact
Communications, JNCC

Back to top