Harbour porpoise - Phocoena phocoena

 

Background

The harbour porpoise (Phocoena phocoena) is a small, highly mobile species of cetacean that is common to all UK waters. However, because of the threat from pressures such as incidental fisheries by-catch, the species has been assessed as under threat/in decline in the Greater North Sea and Celtic Sea, resulting in its recognition as a species of conservation importance under several directives and conventions. This includes Annexes II and IV of the Habitats Directive, Appendix II of the Bonn Convention and the UK Biodiversity Action Plan.

 

Harbour porpoise (Phocoena phocoena) © Peter Evans, Seawatch FoundationHarbour porpoise (Phocoena phocoena) © Colin SpeedieHarbour porpoise (Phocoena phocoena) © M Reichel, Seawatch Foundation

 

An assessment of harbour porpoise conservation status

The Habitat Regulations (HR) for England and Wales (as amended) and the Offshore Marine Conservation (Natural Habitats, &c.) Regulations 2007 (as amended) make it an offence to kill, injure or disturb European marine protected species (e.g. all cetaceans).Similar legislation exists for Scottish and Northern Irish inshore waters.

 

Between the only two wide-scale surveys in the UK and adjacent waters in 1994 and 2005 (Hammond et al., 2002; SCANS II, 2008) there was no evidence of change in the overall abundance of harbour porpoise, but there was evidence of a distributional shift. The largest single threat to small cetaceans - fisheries by-catch - was reported to be diminishing in response to a UK-wide Small Cetacean Bycatch Response Strategy and subsequent long-term monitoring programme, the UK By-catch Monitoring Scheme, to which JNCC contribute.

 

Other threats, such as underwater noise, are also being addressed through the production of good practice guidelines and protocols for marine industries on how to assess the likelihood of committing a disturbance offence to cetaceans such as harbour porpoise, how to avoid it and whether a licence to carry out activity might be required or not. This has resulted in the production of several sets of detailed guidelines covering seismic surveys, pile driving operations and the use of explosives.

 

In the second UK report on implementation of the Habitats Directive, the conservation status of harbour porpoise in UK waters was assessed as favourable with medium confidence, and the species is expected to survive and prosper under the current conservation approach. Continued international collaborative effort to develop appropriate management plans for harbour porpoise has been key to ensuring continued protection of the species. An example is the Conservation Plan for Harbour Porpoises in the North Sea developed between the Parties to ASCOBANS (Agreement on the Conservation of Small Cetaceans of the Baltic and North Seas).

 

Conservation measures to protect harbour porpoise

Conservation efforts that focus on threat/impact reduction, such as fisheries by-catch and underwater noise, coupled with wider surveillance as a mechanism to assess progress and effectiveness, are most likely to achieve effective conservation of harbour porpoise. Cetacean surveillance is being undertaken on a regular basis by a wide variety of agencies, research bodies and voluntary organisations. To enable the results of this surveillance to be used in future assessments of the conservation status of cetaceans, a web-based portal for effort-related sightings data (the Joint Cetacean Protocol) is being developed by JNCC and partners. This will enable our knowledge of the distribution and relative abundance of cetaceans to remain current, thereby ensuring that up-to-date information is available when required and enabling us to assess our approach to harbour porpoise conservation and its effectiveness. Further information on the appropriateness of site based management of harbour porpoise is available.

 

Useful references

DETR, 2003. UK small cetacean bycatch response strategy. Department for the Environment Transport and the Regions

Hammond, P. S., Berggren, P., Benke, H., Borchers, D. L., Collet, A., Heide-Jorgensen, M. P., Heimlich, S., Hiby, A. R., Leopold, M. F. and Øien, N. 2002. Abundance of harbour porpoise and other cetaceans in the North Sea and adjacent waters. Journal of Applied Ecology, 39, pp. 361-376.

Pinn, E., Tasker. M., Mendes., and Goold, J. 2009. Maintaining favourable conservation status of harbour porpoise in UK waters. Available from http://www.jncc.gov.uk/page-5077. Please note that the 2009 paper has been superseeded by a version updated in 2010. Please follow the links on the page link provided.

SCANS II, 2008. Small Cetaceans in the European Atlantic and North Sea. Final Report submitted to the European Commission under project LIFE04NAT/GB/000245. Available from http://biology.st-and.ac.uk/scans2/inner-finalReport.html