While teams battle on the field, stadiums duel with pigeons, seagulls, bats and other flying varmints that terrorize fans and leave horrible messes

Recently at a Denver Broncos game, several fans in $250 seats were bombarded by pigeons all game long. As you can imagine, the fans weren't very happy. But, their situation isn't isolated. Across the country, fans deal with pigeons, bats, seagulls and other flying animals that can make their game experiences miserable. Meanwhile, for those who operate the stadiums, keeping one step ahead of these animals -- that can leave horrible, stinky messes -- is a full-time job. My story for ESPN.com's Playbook section: http://espn.go.com/blog/playbook/fandom/post/_/id/12198/from-pigeons-to-bats-stadiums-combat-pests