Nicholas D. Pyenson
Nicholas D. Pyenson

Integrative biology grad student* Nicholas Pyenson (who also works in the Museum of Paleontology), with two colleagues, worked out the mechanics of the feeding lunges of these giant aquatic mammals and was blown away.

The Fin Whales they were studying — large filter-feeders closely related to the blue and humpback whales — get up to 88 feet long as adults.  They feed in a series of short (six to 10 second) lunges during which they tank up on krill-filled ocean water, then strain out the krill.  Critter-cams have allowed for video observation of the process in recent years, and the skeletons of museum specimens made precise measurements possible.  Armed with that, the biologist came up the probable amount of water a 66-foot adult fin whale gulps in a single lunge: up to 2,900 cubic feet — a volume equal to a school bus.

For the few seconds it takes to squeeze the water (but not the krill) out through its rack of baleen filters, the whale has more than doubled its size.  “The scale of this activity almost defies imagination,” says Pyenson.

Pyenson and Jeremy Goldbogen, a grad student at the University of British Columbia in Vancouver published their finding with zoology professor Robert Shadwick (also of UBC) in the November issue of the journal Marine Ecology Progress Series.

Illustration: This sequence shows the six-second feeding lunge of a fin whale, which can carry it 35 feet forward, letting it collect approximately 25 pounds of krill — and a volume of water equal to a school bus. (graphic: Jeremy Goldbogen and Nicholas Pyenson)
Illustration: This sequence shows the six-second feeding lunge of a fin whale, which can carry it 35 feet forward, letting it collect approximately 25 pounds of krill — and a volume of water equal to a school bus. (graphic: Jeremy Goldbogen and Nicholas Pyenson)

 

Scale objects: Nick Pyenson, upper left, measures the jawbone of a Blue Whale (also a member of the baleen group) at the Canterbury Museum in Christchurch, New Zealand. (photo: R. Ewan Fordyce)
Scale objects: Nick Pyenson, upper left, measures the jawbone of a Blue Whale (also a member of the baleen group) at the Canterbury Museum in Christchurch, New Zealand. (photo: R. Ewan Fordyce)

 

Mealtime: the krill, a swarming life-form similar to shrimp, is a keystone species enjoyed by whales, penguins, seals, squid, fish, and humans (some of whom call it okiami). Many are bioluminescent. They tend to be about one to two centimeters long. Baleen hair, like the teeth on combs, attach to baleen plates and filter whales’ food out of water. Baleen plates were used in buggy whips, parasol ribs, and corsets, but fortunately for whales these mainstays of civilization have gone out of style. (photo: Center for Coastal Studies)
Mealtime: the krill, a swarming life-form similar to shrimp, is a keystone species enjoyed by whales, penguins, seals, squid, fish, and humans (some of whom call it okiami). Many are bioluminescent. They tend to be about one to two centimeters long. Baleen hair, like the teeth on combs, attach to baleen plates and filter whales’ food out of water. Baleen plates were used in buggy whips, parasol ribs, and corsets, but fortunately for whales these mainstays of civilization have gone out of style. (photo: Center for Coastal Studies)

(Originally published in eGrad, December 2007)

* Update: Pyenson received his Ph.D. here in 2008.  He is currently curator of fossil marine mammals at the Smithsonian Institution.  Quote on working in UC Berkeley’s Museum of Paleontology as a student: “It’s like being a kid in a candy store.  There’s literally a thousand dissertations to be done with the materials in our collections.”  More recent quote: “One of the most thrilling and visceral aspects of paleontology is being able to hold or touch the direct records of extinct life.  I think if everyone had the chance to hold a real fossil, even just for a moment, it would improve their appreciation for what they tell us about Earth’s past, future, and our place in the evolutionary tree of life.”


Categories: Student & Alumni Profiles
Tags: ,

About Dick Cortén