During the era of commercial whaling, fin whales were hunted so intensively that only a small percentage of the population in the Southern Hemisphere survived, and even today, marine biologists know little about the life of the world’s second-largest whale.
During the era of commercial whaling, fin whales were hunted so intensively that only a small percentage of the population in the Southern Hemisphere survived, and even today, marine biologists know little about the life of the world’s second-largest whale. That makes the findings of researchers from the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research (AWI) and the Johann Heinrich von Thünen Institute for Sea Fisheries, which show that a large number of the baleen whales regularly frequent the krill-rich waters surrounding Elephant Island, all the more welcome. Evidence for this is provided by underwater sound recordings from the region, where in the peak month of May, so many fin whale vocalizations can be heard that the individual calls merge into a veritable chorous of sound, as the research team now reports in the journal Royal Society Open Science. In view of this, the marine biologists call for protective measures for this important habitat so as not to jeopardise the apparent recovery of the fin whale population.
Fin whales are still rare and, according to the textbooks, normally appear in groups of three to a maximum of seven. As such, AWI marine biologist Elke Burkhardt was all the more surprised when in the late southern summer of 2012, while on an expedition in the Scotia Sea on board the German research icebreaker Polarstern, she counted more than 100 hundred fin whales in the waters north of Elephant Island. Was this a chance find, or did it mean that such large numbers of the world’s second-largest baleen whale gathered here regularly? And if so, why?
To answer this question, in January 2013 Burkhardt and her team installed a mooring with two underwater acoustic recorders and a device used to determine the food supply in the coastal area northwest of the island. Over a period of three years, from January 2013 to February 2016, the instruments recorded the soundscape of the underwater world and gathered data on the food supply in the upper water column. By doing so, they helped identify one of the southern fin whale’s most important habitats.
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