Show Notes
Between 1959 and 1961, between thirty and forty million people starved to death in China. The Great Famine had many causes, and one of them was a campaign to eradicate sparrows. Shaoda Wang of the University of Chicago tells Tim Phillips about Mao Zedong's 1958 Four Pests Campaign, which led to the mass killing of sparrows, set off a chain of consequences that scientists had warned about, but political pressure had silenced. Sparrows eat crops, but they also eat the locusts and other insects that destroy the crops. Remove the sparrows and the pests go unchecked. Wang and his co-authors estimate the eradication cut national grain yields by 8-9%, accounting for roughly a fifth of the total agricultural decline during the famine. The research behind this episode: Frank, Eyal G., Qinyun Wang, Shaoda Wang, Xuebin Wang, and Yang You. 2024. "Campaigning for Extinction: Eradication of Sparrows and the Great Famine in China." NBER Working Paper 34087. To cite this episode: Phillips, Tim, and Shaoda Wang. 2025. "How killing sparrows contributed to the Great Chinese Famine.” VoxDev Talk (podcast).
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About Shaoda Wang
Shaoda Wang is an assistant professor at the Harris School of Public Policy, University of Chicago. His research spans environmental economics, political economy and development, with a focus on how state capacity and political incentives shape environmental and health outcomes in China and other developing countries. Research cited in this episode
The Four Pests Campaign (1958). Launched as part of Mao Zedong's Great Leap Forward, the campaign targeted rats, flies, mosquitoes and sparrows. Sparrows were included on the grounds that they ate grain and reduced agricultural yields. Several prominent Chinese scientists warned at the time that removing sparrows would destabilise the food chain by eliminating a key predator of crop pests, particularly locusts. Their advice was ignored. The campaign resulted in the killing of an estimated two billion sparrows. County gazetteers as a data source. Official harvest data reported by local governments to the central government during the Great Leap Forward was heavily inflated; local officials faced strong political incentives to overstate output, and those exaggerated figures contributed to the famine by masking food shortages from central planners. Wang and his co-authors instead use county gazetteers: records compiled by local elites through a bottom-up process with no link to the political reward structures that distorted official reporting. Comparison between the two sources reveals the scale of over-reporting in the official data. Sparrow habitat suitability index. Rather than relying on reported sparrow kill counts, which were distorted by local officials seeking to demonstrate compliance with campaign targets, the paper constructs an index of how suitable each county's climate and ecological conditions are for sparrow habitation. Counties with high sparrow suitability were more exposed to the shock of eradication; comparing their crop yield and mortality trajectories against low-suitability counties before and after the campaign provides the causal identification strategy. The two groups followed similar trajectories before the campaign; divergence afterwards is attributed to the eradication. State food procurement as a famine amplifier. The Great Famine was not simply a production shortfall. The central government continued to export food during the famine years because inflated harvest reports gave it no signal of the actual crisis. State procurement quotas extracted grain from rural communities at a time when households were already facing starvation; the political system that caused the sparrow eradication was also the mechanism that amplified its consequences. More VoxDev Talks on this topic
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