The researchers needed to know three things: how often whales feed, how big of gulps they take and how much food is in each gulp. “These studies were educated guesses, and none were conducted on live whales in the wild,” says Matthew Savoca, a marine biologist at Hopkins Marine Station of Stanford University in Pacific Grove, Calif.īut new technology gave Savoca and colleagues “a chance to answer a really basic biological question about some of the most charismatic animals on earth.” Previous estimates relied on dissections of dead whales or inferring whales’ metabolic needs based on their size. Whale food intake was coarsely understood before, he says, and this study will “allow us to better understand how the widespread depletion of whales has impacted ocean ecosystems.”Īssessing the precise diet of Boeing 737–sized creatures that gulp down hordes of centimeter-long invertebrates far below the surface of the ocean is not a trivial undertaking. “It’s hard to know what role whales play in ecosystems without knowing how much they’re eating,” says Joe Roman, a marine ecologist at the University of Vermont in Burlington who wasn’t involved in the research. Restoring whale populations to prewhaling levels could help bolster these ecosystems and even store more carbon in the ocean, researchers report in the Nov. Phytoplankton blooms, which sustain krill and many other parts of the food web, rely on that iron. Paradoxically, the collapse of the krill may stem from fewer whales excreting iron-rich, digested krill, denying these ecosystems some crucial nutrients they need to thrive. Now, scientists have a clearer idea why this happened: whale poop, or rather, the lack of it.Ī new study finds that baleen whales, including blue and humpback whales, eat on average three times as much krill and other food as previously thought, and more food in means more poop out. Many other consumers of krill, like seabirds and fish, have suffered too in the absence of the crustaceans and their giant eaters. Instead, Antarctic krill numbers have dwindled since the mid-20th century, by more than 80 percent in areas heavily trafficked by whalers. Some scientists thought that krill - the tiny crustaceans that many whales eat in gargantuan gulps - would explode in number as a result, mostly free from the feeding pressure of the largest animals that have ever lived.īut that didn’t happen. I think we have done more than scratch the surface and we have found lots of exciting stories to tell.Whalers have plucked giant whales from the sea for much of the last century, reducing their numbers by up to 99 percent for certain species. “The problem has been where to start and then … at some point you need to stop. “Sizewise it is quite vast,” said Dobbin. There are also about 50,000 plans and engineering drawings and 5,000 paintings and prints. It includes photos, objects, reels of film and oral testimonies. The show is a partnership with the PLA, which has a remarkable archive on shelves about 1km long. “Younger people don’t remember when so much of London smelled of tobacco.” The scents section at the show will evoke the docks themselves – wood, sea air, sweat – as well as a tea warehouse and the home of a dock worker: “The smell of a coat drying by the fire, the smell of tobacco,” said Dobbin. I don’t notice it until I go out and come back in and think, ‘oh, it smells like a warehouse in here.’” “I’ve learned that you become accustomed to the smell of a room in about seven seconds. “My office smells very much like the docks because I’ve got all the samples here,” she said. Damp wood and sweat … deal porters being trained at Surrey Docks.
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