Yorkshire Philosophical Society

Event Information

Cetaceans in the North Sea

Martin Kitching, Northern Experience

Cetaceans (whales, dolphins and porpoises) number around 90 species worldwide, with 20 of those having occurred off the coast of Northumberland in North East England; an area not previously renowned for its marine mammals other than the impressive Grey Seal population of the Farne Islands.  The majority of those 20 are rare or scarce so this lecture will focus primarily on the four most frequently recorded species: Bottlenose Dolphin, White-beaked Dolphin, Minke Whale and Harbour Porpoise.  Much of what we now know about cetacean occurrence in the North Sea is derived from observations undertaken by citizen scientists over the last 15 years, with topics to be covered including photo-identification as a non-invasive research tool, the power of social media to highlight changes in distribution of some of our most iconic marine megafauna, the expansion in range of the Moray Firth Bottlenose Dolphin population, and the complexity of marine conservation.

7pm in the Tempest Anderson Lecture Theatre in the Yorkshire Museum

Image: Martin Kitching

Member’s report

Martin Kitching gave us a lively account of the cetaceans – dolphins, porpoises and whales – of the North Sea.  Of the 90 species worldwide, 20 have been recorded, and of these only four – the White-beaked and Bottle-nosed Dolphins, the Harbour Porpoise, and the Minke Whale – are ‘regulars’.

Recently, much information about the distribution and habits of these species has come from the coordination of a network of ‘citizen scientist’ observers, correlated with the photo-identification of individuals.  Inevitably, this leaves knowledge gaps; sightings more than a few miles offshore are under-represented; and is an apparent population increase due to an increase in dolphins, or in observers?

However, the information obtained is of immense value in understanding the population dynamics of our iconic marine megafauna. With the White-beaked Dolphin we now know the main feeding, calving and nursery areas – but not where they over-winter, probably in the central North Sea, less accessible to observers. The Bottle-nosed Dolphin was rare in the North Sea, until a pod of around 150 was tracked heading south, possibly in search of cooler water in the central North Sea. This may not be good news for the Harbour Porpoise; males of both dolphin species are known to attack and kill porpoises, possibly mistaking them for unrelated calves of their own species.

The rarer, vagrant whale species find their way into the North Sea occasionally and unintentionally, often recorded only when stranded. Deep sea species can’t easily handle the shallow North Sea environment. Humpbacks may be unable to cope with the powerful sonar echo from a seabed that is so close, while Sperm Whales can’t drink sea water and rely on giant squid as a water source. There are no giant squid in the North Sea.

Martin’s talk was an impressive illustration of the potential of ‘citizen science’ and of volunteer enthusiasm, when appropriately harnessed.  If you want to know more, he does run cetacean-spotting tours out of North Shields!

Peter J Hogarth