Zapper, Zipper, Outfield or Swatting? - Friday's facts, fascinations and folklore

When I was in Mexico this week, I didn't get to see any Caracara's - the national bird of Mexico but did see a male Vermillion Flycatcher.  Always a beautiful sight to behold with those wonderful scarlet feathers.

Photo by Bob Miller

An interesting fact about the vermillion flycatcher is that the male often seeks to initiate copulation by delivering a butterfly or other showy insect to the female.  Maybe the equivalent of oysters, champagne and chocolate????

And if you are ever lucky enough to see a group of vermillion flycatchers hanging out together - be sure to impress your friends by saying "look at that zapper of flycatchers"!  Yes, groups of flycatchers have many collective nouns, including an "outfield", a "swatting", a "zapper" and a "zipper".  I wonder why there are so many words for them?  Anyone know?