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 February 12, 2007
Journal of Experimental Biology 210, 781-787 (2007)
Published by The Company of Biologists 2007
doi: 10.1242/jeb.02708
This Article
Right arrow Summary Freely available
Right arrow Full Text
Right arrow Full Text (PDF)
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 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 Google Scholar
Google Scholar
Right arrow Articles by Schulte-Pelkum, N.
Right arrow Articles by Mauck, B.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Schulte-Pelkum, N.
Right arrow Articles by Mauck, B.

Tracking of biogenic hydrodynamic trails in harbour seals (Phoca vitulina)

N. Schulte-Pelkum, S. Wieskotten, W. Hanke*, G. Dehnhardt and B. Mauck{dagger}

Ruhr-Universität Bochum, Allgemeine Zoologie and Neurobiologie, ND 6/33, D-44780 Bochum, Germany


Figure 1
View larger version (5K):
[in this window]
[in a new window]

  		Fig. 1. Schematic drawing of the experimental pool. (A) Stationing hoop for the test seal. (B) Shallow-water area in which the trail generator was stationed before each trial. (C) Platform on which the trail generator awaited the end of the trial after having generated the trail. The positions marked as –40° to 40° represent the end points of the nine courses of the hydrodynamic trails.

 

Figure 2
View larger version (20K):
[in this window]
[in a new window]

  		Fig. 2. The set-up for the PIV measurements of the seal's wake.

 

Figure 3
View larger version (103K):
[in this window]
[in a new window]

  		Fig. 3. (A) A blindfolded harbour seal starting to track a hydrodynamic trail. Note that the mystacial vibrissae are protracted to the most forward position. (B) A harbour seal correcting its course while tracking a hydrodynamic trail. The seal bends its whole body to swim a curve rather than performing slight lateral scanning movements with its head.

 

Figure 4
View larger version (10K):
[in this window]
[in a new window]

  		Fig. 4. The seal's performance plotted against the nine courses of the hydrodynamic trails.

 

Figure 5
View larger version (85K):
[in this window]
[in a new window]

  		Fig. 5. (A) An exemplary trial showing the seal following a hydrodynamic trail (blue) by a linear pattern (red line). (B) An exemplary trial of hydrodynamic trail-following with an undulatory pattern.

 

Figure 6
View larger version (11K):
[in this window]
[in a new window]

  		Fig. 6. The distribution of the linear and undulatory trail-following patterns over the nine courses of the hydrodynamic trails.

 

Figure 7
View larger version (44K):
[in this window]
[in a new window]

  		Fig. 7. Visualisation of the spatial extent of one of two lateral branches of the trail generator's wake. Each vector field in this figure was reduced to a row by averaging over the columns of the vector field, and the rows resulting from this procedure were assembled in temporal order. Velocities of 80 mm s–1 or higher are dark red.

 




© The Company of Biologists Ltd 2007