Operation Cat Drop
Operation Cat Drop is the name given to the delivery, by the United Kingdom's Royal Air Force, of cats to a remote village in Sarawak, Borneo. The cats were delivered in crates, dropped by parachute, as part of a broader program of supplying cats to combat a plague of rats. Many accounts of the event are of uncertain veracity, however. It is sometimes claimed that the cat population had previously been reduced as an unintended consequence of spraying DDT for malaria control. This story, often with various elaborations, is often told as an illustration of the problems that may arise from well-intended interventions in the environment, or of unintended consequences more generally.
It is not clear whether Operation Cat Drop was linked to the use of insecticides for malaria control or whether cats had died in significant numbers because of the concentration of the insecticides in the food chain. Various aspects of the story have been called into question. For example, it was probably dieldrin rather than DDT which was used for malaria control in the region and then caused numerous cat deaths.
Contemporaneous accounts merely say that cats were required to address rat problems, and these cats were flown out of Singapore by the Royal Air Force and were parachuted in. The operation was reported as a "success" at the time.  These newspaper reports, published soon after the Operation, mention 23 cats being used, much less than the 14,000 mentioned in some later accounts. Contemporaneous reports also describe a "recruitment" drive for 30 cats a few days prior to the Operation proper.
Video footage purporting to show an aerial drop of beavers, intended to improve water quality, appeared in October 2015.
- O'Shaughnessy PT (November 2008). "Parachuting cats and crushed eggs the controversy over the use of DDT to control malaria". Am J Public Health. 98 (11): 1940–8. doi:10.2105/AJPH.2007.122523. PMC 2636426. PMID 18799776.
- "THOSE CATS GO IN BANG ON TARGET". eresources.nlb.gov.sg. Retrieved 2019-08-14.
- "Airdrop cats now go after those rats". eresources.nlb.gov.sg. Retrieved 2019-08-14.
- "It 'rained cats in Sarawak". eresources.nlb.gov.sg. Retrieved 2019-08-14.
- Sandburg, Kyle (2018-02-18). "Operation Cat Drop". Medium. Retrieved 2019-08-14.
- "WANTED: 30 flying cats to rout rats". eresources.nlb.gov.sg. Retrieved 2019-08-14.
- Katie Herzog (23 October 2015). "Beavers are good for streams. Now watch found footage of beavers parachuting". Grist.
- Catdrop.com: a site prepared by Patrick T. O’Shaughnessy, an associate professor at the University of Iowa
- Systems Thinking: Operation Cat Drop and Chaotic Kindness
- World Health Organization (2005). "Operation Cat Drop" (PDF). Quarterly news. 60: 6. Retrieved 2009-08-24.