Florida is treated to significant mass shark migrations annually. Often they are escorting other seasonal migrations of fish (food) along the pennisula. About the only time I have had encounters with sharks while kiting has been when bait were kicking up the surface, birds were fishing, e.g. all the stuff that goes with migrations. So, you can do something else while the migration is moving past your area of Florida. As a rule it doesn't take all that much time, a few days perhaps longer at times. Talk to the local lifeguards to see if the schools have past or not. They may be right, then again, maybe not.
More at:
http://www.cbsnews.com/stories/2005/...in684288.shtml
Some ideas for consideration in dealing with sharks while kiting appear at:
http://www.kiteforum.com/phpbb/viewtopic.php?t=4797