Cocoa production is not keeping up with demand, with a new study published in Communications Earth & Environment highlighting two critical threats to cocoa farming: low pollination rates and rising temperatures.

Researchers from Westlake University, China, conducted field studies in Brazil, Ghana and Indonesia, three of the world’s top cocoa-producing countries, and found pollination is a major bottleneck.

Natural pollination rates averaged just 16.7 percent, meaning most cocoa flowers do not turn into the fruit needed to make chocolate. When the researchers hand-pollinated, they increased yield by 20 percent, confirming that pollination, not soil nutrient levels as previously thought, is the key limiting factor for cocoa production.

Cocoa trees rely mainly on midges to transfer pollen from flower to flower. However, modern cocoa plantations often lack the leaf litter and organic material that these insects need to thrive. Heavy pesticide use and habitat destruction have also impacted pollinator populations.

Cooler temperatures also improved yield by 22 to 31 percent, indicating that climate change is already reducing cocoa production.

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