By Heather Chinn
More than one-and-a-half million whales, dolphins and porpoises are swimming in the waters of the European Atlantic scientists believe, following a huge international count.
Three ships, seven aircraft and a team of scientists from nine countries with Atlantic coastlines surveyed an area of 1.8 million square kilometres from the Straits of Gibraltar in the south to Vestfjorden in Norway in the north, over six weeks in the summer of 2016 to record 19 different species of cetaceans.
The survey is the third to be carried out on such a large scale, similar counts having taken place in 1994 and 2005-07, and a comparison of the results shows the populations of three species - harbour porpoises, white-beaked dolphin and minke whale have remained stable during the 22 years since the first count.
The conservation status of the other cetacean species will require at least one more large-scale survey before they can be assessed, but scientists presenting the results at the European Cetacean Society conference in Denmark, said the counts had already provided them with invaluable information to assess the impact of environmental hazards such as by-catches and pollution on populations.
Professor Phil Hammond of the Sea Mammal Research Unit at the University of St Andrews, Scotland, said: “The results from these large-scale international surveys in the last two decades have greatly expanded our knowledge of the distribution and abundance of cetacean species in European Atlantic waters, giving a strong basis for assessments of conservation status.”
The 2016 survey found the most common species were common dolphins, (counted at 468,000) harbour porpoises (467,000), and striped dolphins (372,000), with a further 158,000 dolphins which were believed to be common or striped.
Other dolphin species recorded were white-beaked dolphins (36,000), bottlenose dolphins (28,000) and white-sided dolphins (16,000).
Deep-diving whales that feed mostly on squid in off shore waters were estimated to be 26,000 pilot whales, 14,000 sperm whales and 11,000 beaked whales of several different species.
Of the filter-feeding baleen whales, 15,000 minke whales and 18,000 fin whales were estimated to be present.
Scientists from Denmark, France, Germany, the Netherlands, Norway, Portugal, Spain, Sweden and the UK collaborated on the survey.
Photo: common dolphins. Credit: © Darren Craig