The Curious Life of Krill: A Conservation Story from the Bottom of the World - Hardcover

Nicol, Stephen

Hardcover

ISBN 10: 1610918533 ISBN 13: 9781610918534

Verlag: Island Press, 2018

Inhaltsangabe

"Makes you feel as if you're part of an engaging dinnertime conversation." —Science News

Krill—it’s a familiar word that conjures oceans, whales, and swimming crustaceans. Scientists say they are one of most abundant animals on the planet. But when pressed, few people can accurately describe krill or explain their ecological importance. Antarctic krill have used their extraordinary adaptive skills to survive and thrive for millions of years in a dark, icy world far from human interference. But with climate change melting ice caps at the top and bottom of the world, and increased human activity and pollution, their evolutionary flexibility to withstand these new pressures may not be enough.

Eminent krill scientist Stephen Nicol wants us to know more about this enigmatic creature of the sea. He argues that it’s critical to understand krill’s complex biology in order to protect them as the krill fishing industry expands. This account of Antarctic krill-one of the largest of eighty-five krill species-takes us to the Southern Ocean to learn firsthand the difficulties and rewards of studying krill in its habitat. Nicol lays to rest the notion that krill are simply microscopic, shrimplike whale food but are in fact midway up the food chain, consumers of phytoplankton and themselves consumed by whales, seals, and penguins. From his early education about the sex lives of krill in the Bay of Fundy to a krill tattoo gone awry, Nicol uses humor and personal stories to bring the biology and beauty of krill alive. In the final chapters, he examines the possibility of an increasingly ice-free Southern Ocean and what that means for the fate of krill-and us.

Ocean enthusiasts will come away with a newfound appreciation for the complex ecology of a species we have much to learn from, and many reasons to protect.

Über diesen Titel

Über die Autorin bzw. den Autor

Stephen Nicol

Auszug. © Genehmigter Nachdruck. Alle Rechte vorbehalten.

The Curious Life of Krill

A Conservation Story from the Bottom of the World

By Stephen Nicol

ISLAND PRESS

Copyright © 2018 Stephen Nicol
All rights reserved.

ISBN: 978-1-61091-853-4

Contents

Foreword, 
Preface, 
Chapter 1: Oceans of Krill, 
Chapter 2: Going with the Floes, 
Chapter 3: Labors of Love, 
Chapter 4: Bringing Krill to Life, 
Chapter 5: Antarctic Fast Food, 
Chapter 6: Eating Krill, 
Chapter 7: Conventional Approaches, 
Chapter 8: Krill Futures, 
Acknowledgments, 
Glossary, 
Further Reading, 
About the Author, 
Index, 

CHAPTER 1

Oceans of Krill

Euphausia — true shining light (Greek)

It was night, and the trawl deck of the Canadian research vessel Dawson was an oasis of light in the inky summer darkness. The ship rolled in the gentle swell, revealing a phosphorescent wake as the stern rose and fell. From the A-frame a single wire stretched taut into the floodlit water, which parted around it in a V-shaped wake as the ship moved slowly forward. At the appropriate signal, the ship's hydraulics groaned into action, and the cable was slowly retrieved from the depths, dripping seawater from the pulley block. A cry of "Sight!" indicated that the net was close to the surface, a pale billowing ghost just visible in the subaquatic greenish light. The drizzling net emerged from the water and was hoisted overhead like an elongated mosquito net. As the wire reached the zenith of the A-frame, the net hung suspended above the glistening deck. The scientific crew sprang into action, using a seawater hose to wash the contents into the net's cod-end — the small container at the end of the net that holds the catch.

Satisfied that every inhabitant of the deep had been flushed into its final resting place in the cod-end, the lead researcher undid the clasp that fastened the cylindrical cod-end to the long, flimsy body of the net. I joined the crowd of eager students on deck as contents were decanted into a plastic tray. "Bugs!" dismissed the professor, as the students enthusiastically poked the rapidly dying catch with tweezers.

A fine-mesh net towed through the water has been standard equipment for sampling the smaller inhabitants of the ocean for more than two hundred years. Because the ocean depths are still one of the planet's great unknowns, there is always a sense of excitement when the contents of a net are heaved onto the deck for examination. The animal life collected in a net has an unforgettable odor — uniquely marine, slightly musty, yet not entirely unpleasant. The animals themselves can vary widely, from wriggling worms to delicate jellies, often crushed and punctured by their unanticipated journey to the surface, to robust amphipod crustaceans that ricochet off the walls of the specimen tray, tiny flealike copepods that twitch their way through the water, and sea snails that appear strangely out of place in the open ocean.

Some larger animals caught my eye — shrimplike creatures that had clearly endured an uncomfortable trip to the surface. These were krill. They lay on their sides, their swimming legs going through the motions, their bodies turning opaque as they slowly died under the glare of the ship's spotlights.

This was my first oceanographic cruise, and my first encounter with living-but-soon-to-be-dead krill. I watched as the tray was whisked away and its contents poured into a jar and topped with formalin — an evil-smelling chemical concoction used to preserve specimens for later analysis. Biological oceanography in the 1970s was essentially this process: dragging a Victorian-era device behind the ship, dispassionately sorting its contents on deck, preserving specimens of interest, and tossing the rest overboard. The exercise was repeated throughout the area of ocean being studied. We gave little thought to the diversity of the sea life we collected, or how the creatures lived and behaved. They were "bugs," zooplankton whose lives were ranked by size, weight, and relative abundance. Through the barrel of a microscope, one animal suspended in formalin looked much like the next.

On a calm day, later that same year, the sun glinted off the gently heaving waters of the Bay of Fundy on the Atlantic coast of North America. Distant flocks of birds hovered above the calmer waters of the oily slicks that meandered across the surface. Our small fishing boat slowly motored toward the signs of biological activity, and I scanned the water for further signs of aquatic life. In the calm, emerald water, rays of sunshine penetrated several meters into the depths of the bay, brightly illuminating surface features, but deeper objects remained indistinct and ghostly. The dense green light of the surface layer distorted the colors of deeper objects. Coastal debris — clumps of seaweed, leaves, twigs, plastic bottles, buoys, and other rubbish associated with fishing communities — had accumulated in the slicks. But below this film there was movement.

Several meters down I could make out a whitish cloud, which gradually turned pink, then red, as it rose to the surface. The cloud became a swarm of thousands of animals with elongated, tapered bodies, swimming in unison and headed in the same direction as if they had a common purpose. As the school neared the surface film, the water turned a rich ochre-red, and I could make out individual krill. Each was about three centimeters (roughly an inch) long, separated by one centimeter from its neighbors. Each probed the water ahead with a set of four antennae, backed up by a pair of bulging black eyes. Krill bodies rippled as their swimming legs propelled them smoothly through the water, their movements perfectly synchronized with those of others in the school. As the krill swarm reached the surface, the school extended their antennae out of the water, and the calm surface rippled from thousands of crustaceans sensing the air. As I watched, mesmerized, this mass of crustaceans became a living, brick-red raft, writhing on top of the water's surface. As if on cue, thousands of krill flipped their muscular tails and leaped clear of the water, falling back like a shower of pink raindrops.

This abundance of densely packaged protein did not go unobserved by the rest of the food chain. The gradual ascent of the krill to the surface was tracked by schools of squid that darted into the aggregations from below, grabbing individual krill with their tentacles, then shooting backward into the ocean's murky depths. Shoals of herring flashed through the krill schools, disrupting their orderly structure and leaving a snowfall of silver scales in their wake. Birds — shearwaters and gulls — squabbled over the smorgasbord of seafood, devouring predator and prey alike. Loud exhalations heralded the arrival of mammals: dolphins and giant fin whales, intent on a meal of krill, fish, and squid, lunged into the krill swarms with mouths agape.

As our boat drifted amongst the swarms of krill and their splashing predators, I watched one long, ribbon-like school of krill moving purposefully past the boat, antennae forward, black eyes prominent, and tails ablur as their swimming legs rhythmically and in unison pushed water away. Each krill maintained a set distance from its neighbors, and the school moved as one — most of the time. As the school passed the boat, one krill broke ranks and swam toward the watching humans, momentarily pausing a meter away. It appeared to check us out before turning around at high speed to rejoin the...

Details zur Ausgabe

• Verlag: Island Press
• Erscheinungsdatum: 2018
• Sprache: Englisch
• ISBN 10: 1610918533
• ISBN 13: 9781610918534
• Einband: Gebundene Ausgabe
• Auflage: 2
• Anzahl der Seiten: 194
• Kontakt zum Hersteller: Nicht verfügbar
• Verantwortliche Person: GPSR Kontakt; gpsr@libri.de; ; Europaallee 1; Bad Hersfeld; 36244; Deutschland