Seven year high for strandings of whales, dolphins and porpoises on UK beaches

A total of 4,896 harbour porpoises, dolphins and whales (cetaceans) were reported washed up on UK shorelines between 1 January 2011 and 31 December 2017, according to a seven-year review published on 6 September 2019 by the UK Government and led by international conservation charity Zoological Society of London (ZSL).

Over the reporting period, researchers from the collaborative UK Cetacean Strandings Investigation Programme (CSIP) recorded 21 different cetacean species – nearly one-quarter of the total currently known to science – as well as six species of marine turtle and several species of large-bodied sharks.

Cornwall Wildlife Trust Marine Strandings Network works in partnership with CSIP to record and monitor strandings in Cornwall, as part of the UK wide project. The county-wide network has been recording strandings in Cornwall and the Isles of Scilly for over 27 years, thanks to the dedication and hard work of hundreds of volunteers.

The report highlights that 2017 was sadly a record-breaking year for cetacean strandings in the UK, and this was replicated in Cornwall with 255 animals washing ashore on Cornish beaches during that year. During the seven years between 2011 and 2017, there was a 15% increase in cetacean strandings across the UK, partly due to the increase in short-beaked common dolphin strandings in the southwest, mainly in Cornwall.

CWTMSN_Nick Dunstone, Holywell Bay 2011, Common Dolphin

Unfortunately, bycatch (accidental entanglement in fishing gear) is one of the most common causes of death for all cetaceans around the UK, accounting for 23% of common dolphin and 14% of harbour porpoise deaths. Here in Cornwall, we have seen an increase in the number of dolphins found with marks and wounds consistent with entanglement in nets and other fishing gear; 20% in 2017 and 31% in 2018 as seen in the latest MSN Strandings report published recently (https://bit.ly/2lFQZAS)

ZSL’s Rob Deaville, Cetologist and report lead explains,

“4,896 is an increase of about 15% on the previous seven-year period. It’s difficult to say conclusively what’s driven this rise, but it’s potentially associated with multiple causes, including increases in local reporting effort and seasonal variation in the population density of some species. As both nets and propellers can cause characteristic injuries, we can readily diagnose causes of death which are directly related to human activity, such as bycatch and ship-strike. However, the total proportion of deaths linked to the impact of humans is actually likely to be higher over the period covered by this report. For example, cases of infectious disease may be associated with exposure to chemical pollution, including legacy pollutants such as PCBs (polychlorinated biphenyls), which can have immunosuppressive effects.”

Niki Clear, Marine Conservation Officer of Cornwall Wildlife Trust adds,

“The southwest of the UK is a hot spot for dolphin and porpoise activity, as well as for water users and fisheries. By monitoring strandings as well as collecting important sightings, through the Marine Strandings Network and surveys of life dolphins and porpoise through Seaquest Southwest, we are getting a real insight into the health of our incredible marine wildlife and the wider environment of Cornwall.”

Cornwall Wildlife Trust as asking anyone on the cliffs and beaches to let us know if you find a dead marine animal washed up, by calling the MSN Strandings Hotline on 0345 201 2626.

And if you are lucky enough to see a pod of dolphins or porpoise around the coast, please make your sighting count and let Seaquest Southwest know.

Find out more about the work Cornwall Wildlife Trust is doing to monitor and protect dolphins and porpoise around the Cornish coast, please visit our website

Marine Strandings Network
www.cornwallwildifetrust.org.uk/strandings
strandings@cornwallwildlifetrust.org.uk

Seaquest Southwest
www.cornwallwildliftrust.org.uk/seaquest
seaquest@cornwallwildlifetrust.org.uk