How Baleen Whales Feed: The Biomechanics of Engulfment and Filtration.
Baleen whales are gigantic obligate filter feeders that exploit aggregations of small-bodied prey in littoral, epipelagic, and mesopelagic ecosystems. At the extreme of maximum body size observed among mammals, baleen whales exhibit a unique combination of high overall energetic demands and low mass-specific metabolic rates. As a result, most baleen whale species have evolved filter-feeding mechanisms and foraging strategies that take advantage of seasonally abundant yet patchily and ephemerally distributed prey resources. New methodologies consisting of multi-sensor tags, active acoustic prey mapping, and hydrodynamic modeling have revolutionized our ability to study the physiology and ecology of baleen whale feeding mechanisms. Here, we review the current state of the field by exploring several hypotheses that aim to explain how baleen whales feed. Despite significant advances, major questions remain about the processes that underlie these extreme feeding mechanisms, which enabled the evolution of the largest animals of all time.
Department of Biology, Hopkins Marine Station, Stanford University, Pacific Grove, California 93950; email: jergold@stanford.edu , davecade@stanford.edu , psegre@stanford.edu.
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JA
Goldbogen
Department of Biology, Hopkins Marine Station, Stanford University, Pacific Grove, California 93950; email: jergold@stanford.edu , davecade@stanford.edu , psegre@stanford.edu.
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DE
Cade
Cascadia Research Collective, Olympia, Washington 98501; email: calambokidis@cascadiaresearch.org.
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J
Calambokidis
Department of Fisheries and Wildlife, Marine Mammal Institute, Hatfield Marine Science Center, Oregon State University, Newport, Oregon 97365; email: ari.friedlaender@oregonstate.edu.
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Friedlaender
Department of Physics, Saint Louis University, St. Louis, Missouri 63103; email: potvinj@slu.edu.
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J
Potvin
Department of Biology, Hopkins Marine Station, Stanford University, Pacific Grove, California 93950; email: jergold@stanford.edu , davecade@stanford.edu , psegre@stanford.edu.
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Segre
Department of Biology, Hampden-Sydney College, Hampden-Sydney, Virginia 23943; email: awerth@hsc.edu.
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Werth
D000818:Animals; D049628:Body Size; D005247:Feeding Behavior; D057446:Hydrodynamics; D014907:Whales
Mysticeti; baleen; drag; feeding; filtration; whale