Here's a ten minute video about America's experiment with bat bombs in World War II. Wikipedia explains:
Bat bombs were bomb-shaped casings with numerous compartments, each containing a Mexican Free-tailed Bat with a small timed incendiary bomb attached. Dropped from a bomber at dawn, the casings would deploy a parachute in mid-flight and open to release the bats which would then roost in eaves and attics. The incendiaries would start fires in inaccessible places in the largely wood and paper construction of the Japanese cities that were the weapon's intended target.Much more here.
Developed by the United States during World War II, four biological factors gave promise to this plan. First, bats occur in large numbers (four caves in Texas are each occupied by several million bats). Second, bats can carry more than their own weight in flight (females carry their young—sometimes twins). Third, bats hibernate, and while dormant they do not require food or maintenance. Fourth, bats fly in darkness, then find secluded places (often in buildings) to hide during daylight.
The plan was to release bat bombs over Japanese cities having widely-dispersed industrial targets. The bats would spread far from the point of release due to the relatively high altitude of their release, then at dawn they would hide in buildings across the city. Shortly thereafter built-in timers would ignite the bombs, causing widespread fires and chaos. The bat bomb idea was conceived by dental surgeon Lytle S. Adams, who submitted it to the White House in January, 1942, where it was subsequently approved by President Roosevelt. Adams was recruited to research and obtain a suitable supply of bats.
UPDATE: Coincidentally, I just saw this:
Roger Dean's album art for "Nitro Function" by Billy Cox. Via these sites.
*Buy propaganda posters at eBay.