Big Balls

Even if you don't fly you've probably noticed those big orange balls attached to power lines (termed 'catenary' by the FAA) stretching across canyons and passes and the like.  The balls' purpose is to warn aviators of the catenary's presence, but as a side benefit they have determined that the balls also alert unsuspecting birds, for which evolution has not yet equipped a need to search for power lines, and have reduced aviary fatalities by up to 50%.


 The FAA has rules for where to put the balls, their spacing and their color.  This is a picture of thousands of catenary balls, ready to be installed by some very skilled and probably slightly crazy helicopter pilot on the new power line project I'm flying on.  


The casual observer may note just simple hemispheres that look a lot like weber grills, but the balls are specially designed to last awhile, because god knows you don't want to be replacing them every five years, and they are also treated to avoid the Corona Effect (a discharging of electricity that can happen when you attach two weber grill shells onto a line carrying a bazillion volts of electricity).  


For you aviator types, if there are multiple balls strung along a length of catenary, the aviation orange ones should be nearest the towers, with alternating colors of orange, white and yellow in between.  If there are fewer than 4 balls, they should all be orange.