Harbour Porpoise

Although smaller and less showy than its relative the dolphin, the harbour porpoise is of no less importance in conservation terms. It is significant in its own right, being the smallest cetacean in UK and Irish waters. Cetaceans are the group of mammals made up of whales, dolphins and porpoises.

Also known as the ‘puffing pig’ (or ‘sea pig’ as the Irish, muc mhara, translates), the harbour porpoise has a blunt rounded snout, measures on average 1.5m in length and weighs 45-85 kg. The animal appears dark grey/black in the water with a paler underside.You’re unlikely to see its belly as it rarely breaches or bow-rides, and will probably only see its small triangular dorsal fin as it surfaces and then ducks underwater in a smooth, rolling motion. It is the most widespread and commonly seen of the six species of porpoise worldwide.

Porpoises feed mostly on non-spiny fish like herring and mackerel, with sand eels also making up a large part of the diet, and need to consume approximately 10% of their body weight each day.

There is some evidence of a decline in numbers of harbour porpoise in UK waters since the 1940s, especially in the southern North Sea and English Channel, but the exact conservation status of the species is poorly understood.

Like all cetaceans, the harbour porpoise is protected under Appendix II of CITES (Convention on International Trade in Endangered Species), Appendix II of the Bern Convention and Annexes II and IV of the EC Habitats Directive. It is also listed as protected on Appendix 2 of the Bonn Convention and is covered by the terms of the Agreement on the Conservation of Small Cetaceans of the Baltic and North Seas (ASCOBANS), a regional agreement under the Bonn Convention. In Northern Ireland it receives specific protection under Schedule 5 of the Wildlife (NI) Order 1985.

Whilst the outlook for harbour porpoises in our waters appears positive, we need to observe population trends to ensure we can react swiftly to negative impacts. At present monitoring is undertaken mainly by volunteers through the Irish Whale and Dolphin Group. To fulfil obligations under the Habitats Directive, important harbour porpoise sites must be identified, designated and managed effectively. In the Republic of Ireland, two Special Areas of Conservation (SACs) have been designated for the harbour porpoise, but in Northern Ireland no such areas have been established. We are lagging behind not only in terms of policy relating to Marine Protected Areas, but in development of comprehensive marine legislation via a Marine Bill for Northern Ireland.

• By-catch (the accidental catching and killing associated with commercial fishing equipment).
• Pollution (e.g. from tiny plastic particles originating from marine debris)
• Over-fishing of prey
• Climate Change
• Noise pollution (e.g. from shipping, underwater construction and operation of equipment)
• Habitat loss

• Report sightings of live and stranded (washed up) harbour porpoises to the Irish Whale and Dolphin Group (IWDG)
• Volunteer with IWDG to undertake regular, dedicated whale watches from a good local vantage point
• Commercial boat operators, particularly those offering wildlife watching experiences, can take part in the WiSE scheme – an accreditation scheme covering codes of practice to ensure safe and unintrusive observation of marine wildlife
• All sea users can help minimise disturbance by behaving responsibly when marine mammals, such as the porpoise, are encountered
• Litter can kill marine wildlife – reduce, re-use and recycle to help cut down on waste, always dispose of litter responsibly and think twice about celebrating events with balloon releases – fragments often end up in the sea and can have deadly consequences for marine animals that ingest them. You can also get involved in a UK wide Beachwatch scheme to carry out local clean ups as well as helping monitor marine litter and its impacts.
• Write to your local MP and/ or MLA about the need for an effective Marine Bill. Click here for a template letter.

Links to more information

www.iwdg.ie

www.habitas.org.uk/priority/species

http://www.ni-environment.gov.uk/