spacer gif spacer gif spacer gif spacer gif spacer gif
 QUICK SEARCH:   [advanced]


spacer gif
     Home     Help     Feedback     Subscriptions     Archive     Search     Table of Contents    

First published online September 9, 2003
This Article
Right arrow Figures Only
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Movie
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Related articles in JEB
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Malkiel, E.
Right arrow Articles by Strickler, J. R.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Malkiel, E.
Right arrow Articles by Strickler, J. R.
The Journal of Experimental Biology 206, 3657-3666 (2003)
doi: 10.1242/jeb.00586

The three-dimensional flow field generated by a feeding calanoid copepod measured using digital holography

Edwin Malkiel1, Jian Sheng1, Joseph Katz1,* and J. Rudi Strickler2

1 Johns Hopkins University, Department of Mechanical Engineering, N. Charles Street, Baltimore, MD 21218, USA
2 Great Lakes WATER Institute, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin 53204, USA

* Author for correspondence (e-mail: Katz{at}jhu.edu)

Accepted 7 July 2003

Digital in-line holography is used for measuring the three-dimensional (3-D) trajectory of a free-swimming freshwater copepod Diaptomus minutus, and simultaneously the instantaneous 3-D velocity field around this copepod. The optical setup consists of a collimated He-Ne laser illuminating a sample volume seeded with particles and containing several feeding copepods. A time series of holograms is recorded at 15 Hz using a lensless 2Kx2K digital camera. Inclined mirrors on the walls of the sample volume enable simultaneous recording of two perpendicular views on the same frame. Numerical reconstruction and matching of views determine the 3-D trajectories of a copepod and the tracer particles to within pixel accuracy (7.4 µm). The velocity field and trajectories of particles entrained by the copepod have a recirculating pattern in the copepod's frame of reference. This pattern is caused by the copepod sinking at a rate that is lower than its terminal sinking speed, due to the propulsive force generated by its feeding current. Consequently, the copepod sees the same fluid, requiring it to hop periodically to scan different fluid for food. Using Stokeslets to model the velocity field induced by a point force, the measured velocity distributions enable us to estimate the excess weight of the copepod (7.2x10-9 N), its excess density (6.7 kg m-3) and the propulsive force generated by its feeding appendages (1.8x10-8 N).

Key words: digital in-line holography, particle image velocimetry, copepod, Diaptomus minutus, flow


Related articles in JEB:

COPEPODS STAR IN 3-D BLOCKBUSTER
Kathryn Phillips
JEB 2003 206: 3538. [Full Text]  



This article has been cited by other articles:


Home page
Proc. Natl. Acad. Sci. USAHome page
J. Sheng, E. Malkiel, J. Katz, J. Adolf, R. Belas, and A. R. Place
Digital holographic microscopy reveals prey-induced changes in swimming behavior of predatory dinoflagellates
PNAS, October 30, 2007; 104(44): 17512 - 17517.
[Abstract] [Full Text] [PDF]


Home page
J. Exp. Biol.Home page
K. B. Catton, D. R. Webster, J. Brown, and J. Yen
Quantitative analysis of tethered and free-swimming copepodid flow fields
J. Exp. Biol., January 15, 2007; 210(2): 299 - 310.
[Abstract] [Full Text] [PDF]


Home page
J PLANKTON RESHome page
A. Albaina and X. Irigoien
Fecundity limitation of Calanus helgolandicus, by the parasite Ellobiopsis sp.
J. Plankton Res., April 1, 2006; 28(4): 413 - 418.
[Abstract] [Full Text] [PDF]


Home page
J PLANKTON RESHome page
E. Malkiel, J. N. Abras, E. A. Widder, and J. Katz
On the spatial distribution and nearest neighbor distance between particles in the water column determined from in situ holographic measurements
J. Plankton Res., February 1, 2006; 28(2): 149 - 170.
[Abstract] [Full Text] [PDF]


Home page
J PLANKTON RESHome page
H. Jiang and J. R. Strickler
Mass density contrast in relation to the feeding currents in calanoid copepods
J. Plankton Res., October 1, 2005; 27(10): 1003 - 1012.
[Abstract] [Full Text] [PDF]


Home page
J. Exp. Biol.Home page
K. Phillips
COPEPODS STAR IN 3-D BLOCKBUSTER
J. Exp. Biol., October 15, 2003; 206(20): 3538 - 3538.
[Full Text] [PDF]




© The Company of Biologists Ltd 2003