Every year, an astonishing number of tennis balls are used during the Wimbledon tournament — more than 54,000 on average. This high figure is due to the fact that tennis balls are replaced at frequent intervals during a match to make sure they aren’t worn down or become too warm to affect the ball’s physical dynamics. Used balls are resold every day at the club to spectators on the grounds, and nearly 700 balls go missing every year, probably taken by the audience and kept as souvenirs. Since 2001, some of these balls are being donated to various animal organizations around Britain that make cute little homes for harvest mice. The Eurasian harvest mouse is typically found in fields of cereal crops, such as wheat and oats, but in recent years their habitat has come under increasing threat from intensive farming and annual floods. Some animal groups then discovered that tennis balls make excellent, waterproof homes for these tiny rodents once you cut a small hole into them. The balls are then attached to poles about three feet off the ground where mice can make their nests in relative safety from birds of prey and weasels, which are too big to get through the hole.
