ABSTRACT: Caribbean whiptail and southern stingrays are large-bodied mesopredators, occupying shallow, nearshore ecosystems of The Bahamas, yet virtually nothing is known of their diet or potential resource competition. We used stomach content analysis via gastric lavage and stable isotope analysis to investigate the diet of 94 Caribbean whiptail rays Styracura schmardae and 112 southern stingrays Hypanus americanus across 3 locations in the central Bahamas. Gastric lavage was used to identify prey consumed and compared to stable isotope analysis of δ¹⁵N, δ¹³C and δ³⁴S of barb, muscle, blood and skin, representing different temporal integration periods. Both species appeared to consume a majority of crustaceans and annelids, although δ¹³C values suggested that Caribbean whiptail rays have larger isotopic niche space across isotopes sampled (potentially broader diet) than southern stingrays, ranging from 5.82-3.43‰², and a greater variance in δ¹³C. This suggests Caribbean whiptail rays potentially feed on prey from either a wider geographic range or from different habitats. Caribbean whiptail and southern stingrays are known to spatio-temporally overlap, and their isotopic niche overlapped by 35.6%. This study represents the first integrated diet estimate for southern stingrays obtained using multiple techniques, and the first ever diet assessment in Caribbean whiptail rays. These data are critical for conservation of coastal ray species and management of coastal and nearshore environments throughout the region.

中文翻译：

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对南方st鱼和加勒比海凤尾鱼的饮食的新颖见解

摘要：加勒比海的ip鱼和南部的黄貂鱼是大型的中捕食者，占据了巴哈马的浅水，近岸生态系统，但实际上对其饮食或潜在的资源竞争一无所知。我们使用了通过洗胃和稳定同位素分析进行​​的胃内容物分析，调查了巴哈马中部3个地点的94头加勒比海凤尾鱼Styracura schmardae和112头南方黄貂鱼Hypanus americanus的饮食。洗胃被用来确定消耗相比，δ稳定同位素分析猎物¹⁵ N，δ ¹³ C和δ ³⁴倒钩，肌肉，血液和皮肤的S，代表不同的时间整合期。这两个物种似乎消耗大部分甲壳类和环节动物，虽然δ ¹³ C值表明，加勒比whiptail的射线具有跨越比南黄貂鱼采样同位素（潜在地更广泛的饮食）放大同位素利基空间，范围从5.82-3.43‰ ²，和更大的方差δ ¹³C.这表明加勒比海ip鱼可能以更广泛的地理范围或不同的栖息地为食。加勒比海的马鞭鱼和南部的黄貂鱼在时空上重叠，它们的同位素位重叠了35.6％。这项研究代表了使用多种技术获得的有关南部黄貂鱼的第一个综合饮食估计值，也是有史以来首次在加勒比海wh鱼中进行的饮食评估。这些数据对于保护整个地区的沿海射线物种以及管理沿海和近岸环境至关重要。