NOTE TO EDITORS: Images of humpback whales are for illustrative purposes only. None of these whales are pictured at Mount Vema. All caption information is embedded with the file.

Researchers recording hundreds of humpback whale calls have discovered a previously unknown "impulsive sound" – dubbed the “gunshot” by researchers – that has never been recorded before. The study documented 600 calls over 11 days at the Vema Seamount in the Atlantic Ocean, 1,000km off the coast of South Africa. The research was conducted during a Greenpeace expedition to the region and led by the universities of Stellenbosch (South Africa) and Exeter (UK).