Understanding the movement ecology of marine species is important for conservation management and monitoring their responses to environmental change. In this study, adult and subadult bull sharks (Carcharhinus leucas; n = 16) were acoustically tagged in Biscayne Bay, Florida (USA), where they were tracked locally via an array of 40 passive acoustic receivers, as well as regionally via cooperative acoustic telemetry networks, with individuals tracked up to 4.5 years. Detection data were used to assess philopatry, regional connectivity, and environmental correlates of shark habitat use. Spatial range varied per individual; however, most individuals displayed high residency to Biscayne Bay, exhibiting strong philopatric behavior to the tagging area. A generalized linear mixed model revealed a seasonal pattern in habitat use, with mature females displaying high residency in Biscayne Bay during the colder dry season (November to February) and lower residencies during the warmer wet season (June to October). These seasonal patterns were supported by catch data from long-term fishery-independent shark surveys in the study area. During summer months when residencies of C. leucas declined in Biscayne Bay, their residencies increased in other regions (e.g., Florida Gulf Coast), demonstrative of seasonal migrations. Connectivity between areas of high use (Biscayne Bay and Florida Gulf Coast) was demonstrated by some individuals traveling between these areas. Results from generalized additive mixed models suggest that these movement patterns could be partially driven by seasonal changes in environmental variables as well as an individual’s life stage, including reproductive status.

了解海洋物种的运动生态学对于保护管理和监测其对环境变化的响应非常重要。在这项研究中，成年和亚成年公鲨（Carcharhinus leucas; n = 16）在美国佛罗里达州的比斯坎湾进行了声学标记，在这里通过40个无源声学接收器的阵列在本地进行了跟踪，并通过合作声学遥测网络在区域进行了跟踪，对个体的跟踪时间长达4.5年。检测数据用于评估鲨鱼栖息地使用的哲学，区域连通性和环境相关性。空间范围因人而异；但是，大多数人都在比斯坎湾居住，对标签区域表现出很强的亲笔行为。广义线性混合模型显示了栖息地使用的季节性模式，成熟的雌性在较干燥的干旱季节（11月至2月）在比斯坎湾显示出较高的居住地，而在较温暖的潮湿季节（6月至10月）显示出较低的居住地。这些季节性模式得到了研究区域长期与渔业无关的鲨鱼调查的渔获数据的支持。在夏季的时候，比斯坎湾的隐孢子虫数量减少，其他地区（例如佛罗里达州墨西哥湾沿岸地区）的隐孢子虫数量增加，表明了季节性迁徙。一些人在这些区域之间旅行证明了高使用区域（比斯坎湾和佛罗里达州墨西哥湾沿岸）之间的连通性。广义加性混合模型的结果表明，这些运动方式可能部分受到环境变量的季节性变化以及个体的生命阶段（包括生殖状态）的影响。