Data from: Columnar cacti as sources of energy and protein for frugivorous bats in a semiarid ecosystem

Columnar cacti constitute the dominant elements in the vegetation structure of arid and semiarid New World ecosystems representing a plethora of food resources for vertebrate consumers. Previous stable isotope analysis in Central Mexico showed that columnar cacti are of low importance to build tissue for frugivorous bats. We used carbon stable isotope analysis of whole blood and breath samples collected from four species of frugivorous bats (Sturnira parvidens, Sturnira ludovici, Artibeus jamaicensis, and Artibeus intermedius) to reconstruct the importance of cactus plants in their diet. Breath samples were collected within 10 min (B10) of bat capture and ~12 h after capture (B720), representing the oxidation of recently ingested food and of body reserves, respectively. We expected that bats relied primarily on non-cactus food to construct tissues and fuel oxidative metabolism. Non-cactus food strongly predominated for tissue building, whereas oxidative metabolism was supported by a moderate preponderance of non-cactus food for B10 samples, and a moderate preponderance of cactus food or an equal contribution of both sources for B720 samples. Artibeus and Surnira species appear to cover a narrow part of the diet with cactus food, con rming that the incorporation of nutrients derived from these plants is not generalized among vertebrate
consumers.

柱状仙人掌（columnar cacti）是新世界干旱与半干旱生态系统植被结构中的优势类群，可为脊椎动物消费者提供极为丰富的食物资源。此前在墨西哥中部开展的稳定同位素分析（stable isotope analysis）显示，柱状仙人掌对于食果蝙蝠的机体组织构建的重要性较低。本研究通过采集4种食果蝙蝠（Sturnira parvidens、Sturnira ludovici、Artibeus jamaicensis及Artibeus intermedius）的全血与呼吸样本，开展碳稳定同位素分析（carbon stable isotope analysis），以此反推仙人掌类植物在其膳食中的贡献程度。呼吸样本分别于蝙蝠捕获后10分钟内（记为B10）以及捕获后约12小时（记为B720）采集，分别对应新近摄入食物的氧化代谢与机体储备的氧化代谢过程。本研究推测，蝙蝠主要依赖非仙人掌类食物完成机体组织构建并为氧化代谢供能。结果表明，机体组织构建几乎完全依赖非仙人掌类食物；对于B10样本，其氧化代谢主要由中等占比的非仙人掌类食物供能，而对于B720样本，氧化代谢则由中等占比的仙人掌类食物供能，或两类食物贡献相当。Artibeus属与Sturnira属蝙蝠的膳食中，仙人掌类食物仅占极小比例，这证实了这类植物来源的营养物质并未在脊椎动物消费者中被广泛利用。