Essex Biodiversity Project
Identification - the harbour porpoise is the only true porpoise species found in European waters. It is the smallest of the British cetacean (Dolphins and Whales) with a total length of 1.5 to 2 metres. It has a small triangular dorsal fin in the centre of its back. It is dark grey with a paler underside, has a small round body with a blunt head and no beak.
General ecology - the harbour porpoise is most often seen within 10km of the shore in small groups or pods of 2-3. They are around all year but more often seen between July and October. They are shy and are unlikely to bow ride (play in front of boats) or breach (leap out of the water). They are found in low numbers around the Essex coast but were probably more common 50 years ago. In 2002, most of the sightings were off the north Essex coast especially the Tendring Peninsular, Jaywick, Clacton and Holland on Sea. The main threats to them are possibly drowning in fishing nets, pollution and fishing.
Surveying tips - The harbour porpoise can be observed from the shore or from a boat. Other cetaceans (Dolphins and Whales) that may be encountered around the Essex coast are Bottlenose Dolphin, White - beaked Dolphin, Longfinned Pilot Whale and the Minke Whale. Records for these are also welcome.
Biodiversity Project Surveys
Since 1999 a recording card, available from Essex Biodiversity project, has been used for recording all of the cetaceans. Dead sightings are useful as well and should be recorded. Essex Biodiversity project also has a listening device called POD that can be deployed to record sonar calls.
Historically, porpoises, dolphins and whales (cetaceaImage: Rohan Holtns) have not been well recorded in the southern North Sea, and Essex coastal waters. In 1995 the Harbour Porpoise, Phocoena phocoena, was added to the UK Biodiversity Action Plan list.
The Harbour porpoise is being surveyed using a POD device and sightings cards which members of the public can complete and return to us. The cards facilitate the collection of protected species data and raises awareness of the presence of these animals along the Essex coastline. The data collected is shared with national conservation organisations.
In 2008, the counties of Essex, Suffolk and Norfolk decided to coordinate their cetacean sightings. This will give a clearer picture of cetacean distribution along the whole of the East Anglian coast, enabling us to provide more effective protection for these elusive animals. A report detailing the sightings in Essex for 2007 to 2008 has been produced.
Harbour Porpoise Survey 2008 (PDF 1.2MB)
The sightings survey card, which includes line drawings of the species likely to be encountered, can be downloaded below. Any sightings of marine mammals can be recorded on the form and returned to us by post or by emailing Mark Iley
Harbour Porpoise Survey card (PDF 265 KB)
For an article giving an overview of the Harbour Porpoise go to http://tinyurl.com/qggfhq