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First published online May 30, 2008
Journal of Experimental Biology 211, 1859-1867 (2008)
Published by The Company of Biologists 2008
doi: 10.1242/jeb.014134
Hydrodynamic performance of the minke whale (Balaenoptera acutorostrata) flipper
1 Department of Anatomy, Northeastern Ohio Universities College of Medicine,
Rootstown, OH 44201, USA
2 School of Biomedical Sciences, Kent State University, Kent, OH 44242,
USA
3 Air Force Research Laboratory, Liquid Rocket Engines Branch, 4 Draco Drive,
Edwards Air Force Base, CA 93524, USA
4 Department of Aerospace Engineering and Engineering Mechanics, San Diego State
University, 5500 Campanile Drive, San Diego, CA 92182, USA
5 2217 Burrough Street, Unit #1, San Diego, CA 92111, USA
6 NASA Jet Propulsion Laboratory, 4800 Oak Grove Drive M/S T1723-118, Pasadena,
CA 91109, USA
7 Department of Anatomy and Pathology, Joan C. Edwards School of Medicine, 1542
Spring Valley Drive, Huntington, WV 25704, USA
8 Department of Ecology and Evolutionary Biology, University of California, Los
Angeles, Box 1606, 621 Charles E. Young Drive South, Los Angeles, CA
90095-1606, USA
9 Department of Biology, West Chester University, 750 S. Church Street, West
Chester, PA 19383, USA
* Author for correspondence (e-mail: l.noelle.cooper{at}gmail.com)
Accepted 1 April 2008
Minke whales (Balaenoptera acutorostrata) are the smallest member
of balaenopterid whales and little is known of their kinematics during feeding
maneuvers. These whales have narrow and elongated flippers that are small
relative to body size compared to related species such as right and gray
whales. No experimental studies have addressed the hydrodynamic properties of
minke whale flippers and their functional role during feeding maneuvers. This
study integrated wind tunnel, locomotion and anatomical range of motion data
to identify functional parameters of the cambered minke whale flipper. A
full-sized cast of a minke whale flipper was used in wind tunnel testing of
lift, drag and stall behavior at six speeds, corresponding to swimming speeds
of 0.7–8.9 m s–1. Flow over the model surface stalled
between 10° and 14° angle of attack (
) depending on testing
speed. When the leading edge was rotated ventrally, loss in lift occurred
around –18° regardless of speed. Range of mobility in the
fresh limb was approximately 40% greater than the range of positive
lift-generating angles of attack predicted by wind tunnel data (+14°
). Video footage, photographs and observations of swimming, engulfment
feeding and gulping minke whales showed limb positions corresponding to low
drag in wind tunnel tests, and were therefore hydrodynamically efficient.
Flippers play an important role in orienting the body during feeding maneuvers
as they maintain trim of the body, an action that counters drag-induced torque
of the body during water and prey intake.
Key words: Cetacea, forelimb, flipper, wind tunnel, hydrodynamics, feeding, control surface, engulfment, lunge
