Theropod tail question

[Raptor <rganuza@luna.cas.usf.edu>]

I know many theropods had stiff tails because of thier vertabrea.  But 
were they completely stiff and unmovable?  This doesn't make any sense to 
me.  Surely they could move them a little.  This is what I picture.  A 
theropod is stalking through the thick foliage.  It knows the prey is 
near. He can hear and smell them.  They are not that far ahead.  He turns 
to conceal himself under the leafy undergrowth when WHAP!  That stiff 
tail held out behind him slaps against some plants.  The sound carries 
through the air like a thundrcrack.  The prey's head whips up and it runs 
off.  The poor theropod sits there growling to itself because it just 
missed a meal.  Is what I picture happening very offten it you have a 
long tail that can't move.  Tell me know what I'm missing here.  Thanks.

                            bite is might

                               Raptor     <O)
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