To meet the growing demand for chocolate, cocoa (Theobroma cacao) agriculture is expanding and intensifying. Although this threatens tropical forests, cocoa sustainability initiatives largely overlook biodiversity conservation. To inform these initiatives, we analyzed how cocoa agriculture affects bird diversity at farm and landscape scales with a meta-analysis of 23 studies. We extracted 214 Hedges' g* comparisons of bird diversity and 14 comparisons of community similarity between a forest baseline and 4 farming systems that cover an intensification gradient in landscapes with high and low forest cover, and we summarized 119 correlations between cocoa farm features and bird diversity. Bird diversity declined sharply in low shade cocoa. Cocoa with >30% canopy cover from diverse trees retained bird diversity similar to nearby primary or mature secondary forest but held a different community of birds. Diversity of endemic species, frugivores, and insectivores (agriculture avoiders) declined, whereas diversity of habitat generalists, migrants, nectarivores, and granivores (agriculture associates) increased. As forest decreased on the landscape, the difference in bird community composition between forest and cocoa also decreased, indicating agriculture associates replaced agriculture avoiders in forest patches. Our results emphasize the need to conserve forested landscapes (land sparing) and invest in mixed-shade agroforestry (land sharing) because each strategy benefits a diverse and distinct biological community.

中文翻译：

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可可农业集约化对鸟类多样性和群落组成的影响

为了满足对巧克力日益增长的需求，可可（Theobroma cacao）农业正在扩大和加强。尽管这威胁到热带森林，但可可可持续性倡议在很大程度上忽视了生物多样性保护。为了为这些举措提供信息，我们通过对 23 项研究的荟萃分析分析了可可农业如何影响农场和景观尺度的鸟类多样性。我们提取了 214 Hedges 的g* 比较森林基线和 4 个农业系统之间的鸟类多样性比较和群落相似性的 14 个比较，这些农业系统涵盖了森林覆盖率高和低的景观中的集约化梯度，我们总结了 119 个可可农场特征与鸟类多样性之间的相关性。低荫可可的鸟类多样性急剧下降。来自不同树木的树冠覆盖率 > 30% 的可可保留了类似于附近原始或成熟次生林的鸟类多样性，但拥有不同的鸟类群落。特有物种、食果动物和食虫动物（农业回避者）的多样性下降，而栖息地通才、迁徙、蜜食动物和食谷动物（农业伙伴）的多样性增加。随着景观上森林的减少，森林和可可之间鸟类群落组成的差异也减少了，表明农业伙伴取代了森林斑块中的农业回避者。我们的研究结果强调了保护森林景观（土地节约）和投资混合遮荫农林业（土地共享）的必要性，因为每种策略都有益于多样化和独特的生物群落。