ATLANTIC GREY SEAL (HALICHOERUS GRYPUS)
ATLANTIC GREY SEAL (HALICHOERUS GRYPUS)
LOCAL BIODIVERSITY ACTION PLAN
Atlantic grey seals reach up to 2.3m in length and weigh between 150-315kg. The coat colour is often blotchy and can vary from grey or silver to brown. Males have a continuous dark coloured background whereas the females have a lighter background. Juveniles are born with a creamy white natal coat. The nostrils are parallel and the 'Roman nose' is characteristic especially in male seals.
Grey seals usually haul out on uninhabited offshore islands, but will occasionally be found on quiet mainland beaches.
Grey seals dive up to depths of 70m to feed on a wide range of fish species however they also feed on crustaceans, cephalopods and the occasional sea bird.
Grey seals live for 30-40 years. In autumn females congregate at traditional pupping sites, known as rookeries. Males then come ashore to compete for sole access to a group of females (a dominant male can secure access to up to 10 females). After mating the seals disperse. The pups stay at the rookery surviving on their blubber reserves until the moult has occurred and then they too disperse.
A baseline study placed the number of grey seal in the UK and Northern Ireland in 1988 at 110,000. (International Fund for Animal Welfare). The current figure is likely to be considerably higher.
On Wirral, grey seal occupy the east side of the West Hoyle sand bank, near to the Hilbre islands. The Hilbre population do not breed in the Dee. They use the Liverpool Bay area to haul out, feed and moult. Small numbers of seals venture into the Mersey Estuary.
It has been generally accepted that they breed on rocky islands on or around Ramsey Island in West Wales, though recently this idea has been challenged. It was noted that the north end of Hilbre was used by a small number of grey seals during the war years. Occasionally 1 or 2 Grey seals still haul out here. The West Hoyle gathering is composed entirely of grey seal, though occasional Common seal are also present in the area.
The earliest positive identification of a grey seal in the Hilbre area is that quoted by Coward (1910): '28 October, 1909, - a young (3 feet 3 inches) Grey Seal was stranded on a bank off Hoylake, captured by fishermen ... secured alive for the Liverpool Museums.' The seals were first known to use the West Hoyle bank as a haul out during 1928. Craggs and Ellison reviewed the situation and documented the dramatic increase in numbers using the haul out between 1951 and 1957. The maximum count for August 2000 was 579.
The grey seal is on the Biodiversity UK Steering Group Report long list of globally threatened/declining species. It is currently listed as a protected species under Annex II and Annex V of the European Community's Habitats Directive and several important sites for grey seal have been proposed in EC member countries as Special Areas of Conservation under the Directive. The grey seal is also listed as an Appendix III species under the Bern Convention.
The Dee Estuary SSSI cites seals as a species of regional interest under reasons for notification. Further protection for the seal's habitat is given by SPA, RAMSAR and cSAC designations.
* Pollution - plastic litter and toxic chemicals including oil spills
* Disease - eg. Phocine distemper virus (PDV)
* The threat of large scale culls due to interaction with fisheries
* Fisheries by-catch
* Poaching of baby seals for fur
* Licensed shooting of seals by fisheries
* Human disturbance from boats, jet skis, seal watching trips and aircraft
* Collision with boats and fishing nets.
How are we helping to conserve Atlantic Grey Seals in the Cheshire region?
* Wirral Rangers provide information to schools, colleges, other groups and general public about seals. Information is conveyed in a variety of forms, for example in Hilbre walks, leaflets, slide talks about the coast, and in notice boards. Visitors to Hilbre are encouraged to look at the seals through telescopes.
* The Countryside Council for Wales carried out a research project to establish the distribution of grey seal and census of pups in North Wales during 2001. The study is to be repeated for 2002. Guidance and protocols for monitoring are being developed as part of the project. Photo identification is also being tried out as a method of establishing breeding locations and interplay between sites.
* Hilbre Bird Observatory also inform the public about the seals. They have conducted counts on a daily basis (when personnel are available) since 1957. Also recorded are weather, disturbance and comments. Maximum monthly figures are published in their annual report and some of the data is available in electronic form from the Records Secretary. The annual report is available for sale direct from the Bird Observatory or via the internet.
* An MSc research project was carried out in 2002, on behalf of the Mersey Strategy to investigate the feasibility of using marine mammals (including grey seals) as indicators of the environmental health of estuaries.
Objectives, Targets and Actions
The objectives, targets and actions to help conserve the Atlantic Grey Seals in the Cheshire region can be found on the Biodiversity Action Reporting System (BARS) along with full details of our progress so far.
How to find out more about Atlantic Grey Seals?
Hilbre Bird Observatory - www.hilbrebirdobs.blogspot.com
International Fund for Animal Welfare - www.ifact.org/Seals
Grey Seal Conservation Society - www.greyseal.net
How can you get involved?
If you see a seal in need of rescue, please phone:
Dave Cavanagh, Hilbre Ranger (0151 632 4455),
Dave Holden, WMBC Dog Warden (0151 647 8799)
References & Glossary
Anderson S., The Grey Seal, 1988, no 26 in the Shire Natural History series. Shire Publications Ltd. ISBN 085263 947 3.
Anderson S., Seals, Whittet Books, London.
Craggs J.D., Hilbre the Cheshire Island, Liverpool University Press, 1982.
Hilbre Bird Observatory Annual Reports.
Westcot Steven, The Distribution of Grey Seals (Halichoerus grypus) and Census of Pup Production on North Wales. Countryside Council for Wales Science Report No.499. 2002.
Mammal Society fact sheet. (January 2002):