Invertivorous fish species such as Halichoeres radiatus feed on benthic active prey and need to spend most of their time foraging. Even though the Labridae family is one of the most speciose in reef environments, the knowledge on feeding habits and behavior of this group continues being a major topic on trophic ecology. The present work aimed to evaluate the feeding behavior, diet, and the substrate selectivity of H. radiatus in the remote Saint Peter and Saint Paul Archipelago (SPSPA), where this is the only species of this trophic group, and adds understanding about the role of this species in this singular system. Individuals of H. radiatus were captured and had their diet analyzed in the laboratory to identify and quantify their food items. Direct observations using scuba diving were also performed to describe the daily foraging frequency. Photoquadrats were taken to estimate the substrate relative cover, as a proxy of resource availability. The diet of H. radiatus in SPSPA was mainly composed of damselfish eggs and crustaceans in addition to gastropods, mollusks, and sponges, which reinforces its generalist feeding habits. Individuals of H. radiatus foraged mainly on substrates composed by epilithic algal matrix, which was the most abundant substrate in the study area, but preferred bare rocks and sediment. The foraging activity was constant throughout the daytime, decreasing at sunset. Our results suggest that H. radiatus has a generalist habit, supporting the idea that it is a versatile species, foraging all day long, and constituting an important link in the trophic chain of the archipelago.

反食性鱼类，如Halichoeres radiatus以底栖活跃的猎物为食，需要花费大部分时间觅食。尽管 Labridae 家族是珊瑚礁环境中最有特色的家族之一，但关于这一群体的摄食习惯和行为的知识仍然是营养生态学的一个主要话题。目前的工作旨在评估偏远的圣彼得和圣保罗群岛 (SPSPA) 中辐射 H. radiatus的摄食行为、饮食和底物选择性，这是该营养组中唯一的物种，并增加了对作用的理解在这个单一系统中的这个物种。H. radiatus个体被捕获并在实验室分析他们的饮食，以识别和量化他们的食物。还进行了使用水肺潜水的直接观察来描述每日觅食频率。Photoquadrats 被用来估计底物的相对覆盖率，​​作为资源可用性的代表。SPSPA 中的H. radiatus的饮食主要由雀鲷卵和甲壳类动物以及腹足类动物、软体动物和海绵组成，这加强了其普遍的摄食习惯。H. radiatus个体主要以表石藻基质组成的基质为食，该基质是研究区最丰富的基质，但更喜欢裸岩和沉积物。觅食活动在白天是恒定的，在日落时减少。我们的结果表明H. radiatus有一个多面手的习惯，支持它是一个多才多艺的物种的观点，整天觅食，并构成群岛营养链中的一个重要环节。