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TWL: Hydroplaning by ducklings: overcoming limitations to swimming at the water surface

geneu@erols.com

Fri, Nov 5, 1999 1:19 AM

Thanks for all the useful information
Gene Ullrich
Arlington, Virginia
Current sailor actively pursuing the purchase of a trawler.

http://www.biologists.com/JEB/198/07/jeb9812.html

<head> <title>Hydroplaning by ducklings: overcoming limitations to swimming at the water surface</title> <meta name="keywords" content="Company of Biologists, The Journal of Experimental Biology, hydroplaning, ducklings, wave drag, swimming kinematics, mallard, Anas platyrhynchos., Cell"> <base href="http://www.biologists.com/JEB/198/07/jeb9812.html"> </head> <body bgcolor = "#ffffff" text = "#000000" link = "#0000cc" alink = "#000099" vlink = "#000099"> <center> <table width=600 border=0 cellspacing=0 cellpadding=0> <tr> <td width=504 align=left valign=top> <img src="/images/jebtitle.gif" alt="The Journal of Experimental Biology" width=330 height=82 border=0> <hr noshade size=1> </td> <td width=96 align=right valign=top> <a href="/mirror.cgi"><img src="/images/cobmirror.gif" alt="The Company of Biologists Limited" width=96 height=96 border=0></a> </td></tr> <tr><td width=600 align=left valign=top colspan=2> <table cellspacing=0 cellpadding=0 border=0 width=100%> <tr><td align=left valign=bottom>

<font size="+1" face="Helvetica,Arial" color="#990000"><b>Volume 198 (7) 1995</b></font>

</td><td align=right valign=bottom> <a href="index.html"><img src="/images/up.gif" alt="Up" width=12 height=12 border=0></a> <a href="/nav.cgi?JEB/198/07/jeb9812+prev"><img src="/images/prev.gif" alt="Previous" width=12 height=12 border=0></a> 1567-1574 <a href="/nav.cgi?JEB/198/07/jeb9812+next"><img src="/images/next.gif" alt="Next" width=12 height=12 border=0></a> </td></tr> </table> </td> </tr> </table> <table width=600 border=0 cellspacing=0 cellpadding=0> <tr> <td width=100 align=left valign=top> <table width=100 cellspacing=0 cellpadding=0 border=0> <tr><td valign=top width=10><img src="/images/arrow.gif" width=10 height=12 border=0></td> <td valign=top> <a href="/" style="text-decoration:none;"> <font color="#000000" face="Helvetica Narrow, Arial Narrow, Helvetica, Arial, Geneva" size=2><b>Home</b></font></a> </td></tr> <tr><td valign=top width=10><img src="/images/arrow.gif" width=10 height=12 border=0></td> <td valign=top> <a href="/JEB/" style="text-decoration:none;"> <font color="#000000" face="Helvetica Narrow, Arial Narrow, Helvetica, Arial, Geneva" size=2><b>Journal of Experimental Biology</b></font></a> <a href="/JEB/all.html" style="text-decoration:none;"> <font color="#000000" face="Helvetica Narrow, Arial Narrow, Helvetica, Arial, Geneva" size=2><b> Contents</b></font></a> <a href="/JEB/contribute.html" style="text-decoration:none;"> <font color="#000000" face="Helvetica Narrow, Arial Narrow, Helvetica, Arial, Geneva" size=2><b> Authors</b></font></a> <a href="/JEB/subscribe/" style="text-decoration:none;"> <font color="#000000" face="Helvetica Narrow, Arial Narrow, Helvetica, Arial, Geneva" size=2><b> Subscribe</b></font></a> <a href="/JEB/../search-cgi/fastweb?view=simple&TemplateName=search.tmpl" style="text-decoration:none;"> <font color="#000000" face="Helvetica Narrow, Arial Narrow, Helvetica, Arial, Geneva" size=2><b> Search</b></font></a> </td></tr> <tr><td valign=top width=10><img src="/images/arrow.gif" width=10 height=12 border=0></td> <td valign=top> <a href="/Development/" style="text-decoration:none;"> <font color="#000000" face="Helvetica Narrow, Arial Narrow, Helvetica, Arial, Geneva" size=2><b>Development</b></font></a> </td></tr> <tr><td valign=top width=10><img src="/images/arrow.gif" width=10 height=12 border=0></td> <td valign=top> <a href="/JCS/" style="text-decoration:none;"> <font color="#000000" face="Helvetica Narrow, Arial Narrow, Helvetica, Arial, Geneva" size=2><b>Journal of Cell Science</b></font></a> </td></tr> <tr><td valign=top width=10><img src="/images/arrow.gif" width=10 height=12 border=0></td> <td valign=top> <a href="/search-cgi/fastweb?view=simple&TemplateName=search.tmpl" style="text-decoration:none;"> <font color="#000000" face="Helvetica Narrow, Arial Narrow, Helvetica, Arial, Geneva" size=2><b>Search</b></font></a> </td></tr> <tr><td valign=top width=10><img src="/images/arrow.gif" width=10 height=12 border=0></td> <td valign=top> <a href="/cob/help/" style="text-decoration:none;"> <font color="#000000" face="Helvetica Narrow, Arial Narrow, Helvetica, Arial, Geneva" size=2><b>Help</b></font></a> </td></tr> <tr><td colspan=2> <a href="/cob/map.html"><img src="/images/sitemap.gif" width=100 height=75 border=0></a> </td></tr> </table> </td> <td width=500 align=left valign=top rowspan=2> <h2>Hydroplaning by ducklings: overcoming limitations to swimming at the water surface</h2> <h4>Terrye L. Aigeldinger and Frank E. Fish</h4> <h3><font color="#990000">Summary</font></h3>

Rapid escape behavior by mallard (<I>Anas</I> <I>platyrhynchos</I>) ducklings is restricted to burst swimming at the water surface. Maximum speed may be limited because of the pattern of waves created as the duckling's body moves through the water (hull speed). Burst speeds for 9-day-old ducklings were compared with predicted hull speeds, based on the waterline length of ducklings either resting in water or actively swimming. Kinematic analysis of video tapes showed a mean maximum burst speed of 1.73 m s<SUP>-1</SUP>, which was four times greater than the predicted hull speed. At burst velocities, stroke frequency was 1.9 times higher than the stroke frequency measured during steady low-speed paddling. Transition to burst speeds from steady paddling occurred near predicted hull speed. The paddling motions of the webbed feet were used to generate both thrust and lift. By using lift to raise the body above the water surface, the influence of waves in restricting maximum swimming speed is negated. The duckling's body becomes a planing type of hull and skims on the water surface.

Key words:
hydroplaning, ducklings, wave drag, swimming kinematics, mallard, <I>Anas platyrhynchos</I>.

<table width=100% cellspacing=0 cellpadding=0 border=0> <tr><td align=left> <a href="/serve.cgi?JEB/198/07/jeb9812.pdf"> <img src="/images/fulltext.gif" width=88 height=31 alt="Full Text (Acrobat pdf)" border=0></a> (<i>192 Kb</i>) </td><td align=right> <a href="http://www.adobe.com/acrobat/readstep.html"> <img src="/images/getacro.gif" width=88 height=31 alt="Get Acrobat!" border=0></a> </td></tr> <tr><td colspan=2> </td></tr> <tr><td colspan=2 align=center> <map name="navbar"> <area shape="rect" coords=" 0, 0, 97, 27" href="/nav.cgi?JEB/198/07/jeb9812+qbe"> <area shape="rect" coords=" 98, 0, 197, 27" href="jeb9812t.html"> <area shape="rect" coords="198, 0, 297, 14" href="/refer.cgi/JEB/198/07/jeb9812.txt"> <area shape="rect" coords="198,15, 297, 27" href="/cob/help/index.html#refer"> <area shape="rect" coords="298, 0, 397, 27" href="jeb9812f.html"> <area shape="rect" coords="398, 0, 495, 27" href="jeb9812p.html"> </map> <a href="jeb9812.html"><img src="/images/navbar.gif" usemap="#navbar" border=0></a> </td></tr> </table> </td></tr> <tr><td valign=bottom> <img src="/images/biocob.gif" alt="" width=100 height=55 border=0> </td></tr> </table> <table width=600 border=0 cellspacing=0 cellpadding=0> <tr> <td width=600 align=left valign=top colspan=2> <hr noshade size=1> © <a href="/copy.html"><b>Copyright The Company of Biologists Ltd. 1999</b></a> </td></tr> <tr><td align=left> Feedback / Problems? </td><td align=right> Contact: Webmaster@biologists.com </td></tr> </table> </center> </body>

Greeting all: I'm new to the TWL and lists in general. Like Andrew Woods, I've been lurking since the Solomons fest and probably I'll continue to lurk for a while. Like Andrew, I also believe I have something to add to what appears to be a continuing discussion. I would be interested in Paul Kruse's thoughts and comments on the attached scientific journal article. Thanks for all the useful information Gene Ullrich Arlington, Virginia Current sailor actively pursuing the purchase of a trawler. http://www.biologists.com/JEB/198/07/jeb9812.html <head> <title>Hydroplaning by ducklings: overcoming limitations to swimming at the water surface</title> <meta name="keywords" content="Company of Biologists, The Journal of Experimental Biology, hydroplaning, ducklings, wave drag, swimming kinematics, mallard, Anas platyrhynchos., Cell"> <base href="http://www.biologists.com/JEB/198/07/jeb9812.html"> </head> <body bgcolor = "#ffffff" text = "#000000" link = "#0000cc" alink = "#000099" vlink = "#000099"> <center> <table width=600 border=0 cellspacing=0 cellpadding=0> <tr> <td width=504 align=left valign=top> <img src="/images/jebtitle.gif" alt="The Journal of Experimental Biology" width=330 height=82 border=0> <hr noshade size=1> </td> <td width=96 align=right valign=top> <a href="/mirror.cgi"><img src="/images/cobmirror.gif" alt="The Company of Biologists Limited" width=96 height=96 border=0></a> </td></tr> <tr><td width=600 align=left valign=top colspan=2> <table cellspacing=0 cellpadding=0 border=0 width=100%> <tr><td align=left valign=bottom> <font size="+1" face="Helvetica,Arial" color="#990000"><b>Volume 198 (7) 1995</b></font> </td><td align=right valign=bottom> <a href="index.html"><img src="/images/up.gif" alt="Up" width=12 height=12 border=0></a> <a href="/nav.cgi?JEB/198/07/jeb9812+prev"><img src="/images/prev.gif" alt="Previous" width=12 height=12 border=0></a> 1567-1574 <a href="/nav.cgi?JEB/198/07/jeb9812+next"><img src="/images/next.gif" alt="Next" width=12 height=12 border=0></a> </td></tr> </table> </td> </tr> </table> <table width=600 border=0 cellspacing=0 cellpadding=0> <tr> <td width=100 align=left valign=top> <table width=100 cellspacing=0 cellpadding=0 border=0> <tr><td valign=top width=10><img src="/images/arrow.gif" width=10 height=12 border=0></td> <td valign=top> <a href="/" style="text-decoration:none;"> <font color="#000000" face="Helvetica Narrow, Arial Narrow, Helvetica, Arial, Geneva" size=2><b>Home</b></font></a> </td></tr> <tr><td valign=top width=10><img src="/images/arrow.gif" width=10 height=12 border=0></td> <td valign=top> <a href="/JEB/" style="text-decoration:none;"> <font color="#000000" face="Helvetica Narrow, Arial Narrow, Helvetica, Arial, Geneva" size=2><b>Journal of Experimental Biology</b></font></a> <a href="/JEB/all.html" style="text-decoration:none;"> <font color="#000000" face="Helvetica Narrow, Arial Narrow, Helvetica, Arial, Geneva" size=2><b> Contents</b></font></a> <a href="/JEB/contribute.html" style="text-decoration:none;"> <font color="#000000" face="Helvetica Narrow, Arial Narrow, Helvetica, Arial, Geneva" size=2><b> Authors</b></font></a> <a href="/JEB/subscribe/" style="text-decoration:none;"> <font color="#000000" face="Helvetica Narrow, Arial Narrow, Helvetica, Arial, Geneva" size=2><b> Subscribe</b></font></a> <a href="/JEB/../search-cgi/fastweb?view=simple&TemplateName=search.tmpl" style="text-decoration:none;"> <font color="#000000" face="Helvetica Narrow, Arial Narrow, Helvetica, Arial, Geneva" size=2><b> Search</b></font></a> </td></tr> <tr><td valign=top width=10><img src="/images/arrow.gif" width=10 height=12 border=0></td> <td valign=top> <a href="/Development/" style="text-decoration:none;"> <font color="#000000" face="Helvetica Narrow, Arial Narrow, Helvetica, Arial, Geneva" size=2><b>Development</b></font></a> </td></tr> <tr><td valign=top width=10><img src="/images/arrow.gif" width=10 height=12 border=0></td> <td valign=top> <a href="/JCS/" style="text-decoration:none;"> <font color="#000000" face="Helvetica Narrow, Arial Narrow, Helvetica, Arial, Geneva" size=2><b>Journal of Cell Science</b></font></a> </td></tr> <tr><td valign=top width=10><img src="/images/arrow.gif" width=10 height=12 border=0></td> <td valign=top> <a href="/search-cgi/fastweb?view=simple&TemplateName=search.tmpl" style="text-decoration:none;"> <font color="#000000" face="Helvetica Narrow, Arial Narrow, Helvetica, Arial, Geneva" size=2><b>Search</b></font></a> </td></tr> <tr><td valign=top width=10><img src="/images/arrow.gif" width=10 height=12 border=0></td> <td valign=top> <a href="/cob/help/" style="text-decoration:none;"> <font color="#000000" face="Helvetica Narrow, Arial Narrow, Helvetica, Arial, Geneva" size=2><b>Help</b></font></a> </td></tr> <tr><td colspan=2> <a href="/cob/map.html"><img src="/images/sitemap.gif" width=100 height=75 border=0></a> </td></tr> </table> </td> <td width=500 align=left valign=top rowspan=2> <h2>Hydroplaning by ducklings: overcoming limitations to swimming at the water surface</h2> <h4>Terrye L. Aigeldinger and Frank E. Fish</h4> <h3><font color="#990000">Summary</font></h3> Rapid escape behavior by mallard (<I>Anas</I> <I>platyrhynchos</I>) ducklings is restricted to burst swimming at the water surface. Maximum speed may be limited because of the pattern of waves created as the duckling's body moves through the water (hull speed). Burst speeds for 9-day-old ducklings were compared with predicted hull speeds, based on the waterline length of ducklings either resting in water or actively swimming. Kinematic analysis of video tapes showed a mean maximum burst speed of 1.73 m s<SUP>-1</SUP>, which was four times greater than the predicted hull speed. At burst velocities, stroke frequency was 1.9 times higher than the stroke frequency measured during steady low-speed paddling. Transition to burst speeds from steady paddling occurred near predicted hull speed. The paddling motions of the webbed feet were used to generate both thrust and lift. By using lift to raise the body above the water surface, the influence of waves in restricting maximum swimming speed is negated. The duckling's body becomes a planing type of hull and skims on the water surface. Key words: hydroplaning, ducklings, wave drag, swimming kinematics, mallard, <I>Anas platyrhynchos</I>. <table width=100% cellspacing=0 cellpadding=0 border=0> <tr><td align=left> <a href="/serve.cgi?JEB/198/07/jeb9812.pdf"> <img src="/images/fulltext.gif" width=88 height=31 alt="Full Text (Acrobat pdf)" border=0></a> (<i>192 Kb</i>) </td><td align=right> <a href="http://www.adobe.com/acrobat/readstep.html"> <img src="/images/getacro.gif" width=88 height=31 alt="Get Acrobat!" border=0></a> </td></tr> <tr><td colspan=2> </td></tr> <tr><td colspan=2 align=center> <map name="navbar"> <area shape="rect" coords=" 0, 0, 97, 27" href="/nav.cgi?JEB/198/07/jeb9812+qbe"> <area shape="rect" coords=" 98, 0, 197, 27" href="jeb9812t.html"> <area shape="rect" coords="198, 0, 297, 14" href="/refer.cgi/JEB/198/07/jeb9812.txt"> <area shape="rect" coords="198,15, 297, 27" href="/cob/help/index.html#refer"> <area shape="rect" coords="298, 0, 397, 27" href="jeb9812f.html"> <area shape="rect" coords="398, 0, 495, 27" href="jeb9812p.html"> </map> <a href="jeb9812.html"><img src="/images/navbar.gif" usemap="#navbar" border=0></a> </td></tr> </table> </td></tr> <tr><td valign=bottom> <img src="/images/biocob.gif" alt="" width=100 height=55 border=0> </td></tr> </table> <table width=600 border=0 cellspacing=0 cellpadding=0> <tr> <td width=600 align=left valign=top colspan=2> <hr noshade size=1> © <a href="/copy.html"><b>Copyright The Company of Biologists Ltd. 1999</b></a> </td></tr> <tr><td align=left> Feedback / Problems? </td><td align=right> Contact: Webmaster@biologists.com </td></tr> </table> </center> </body>