Collaborative Research: Linking behavior and transport of larvae using waves and turbulence as cues

许多生活在海底的海洋物种都有幼虫，其在水柱中的行为会影响扩散和成体分布。蜗牛幼虫对波浪和湍流的暗示做出更大的努力或下沉，目前尚不清楚幼虫是否可以利用这些物理线索在栖息地内保留或在栖息地之间导航。在海浪下向上游动的幼虫可以通过海浪引起的表层水域的岸上漂流而留在大陆架上。然而，海洋变暖导致幼虫在春季更早地释放，此时海浪更大，海岸上升流更弱，可能会将幼虫带到超过成虫温度耐受性的浅水中。研究人员将使用大西洋中部海湾和邻近河口的物理模型来测试有关海浪和湍流如何影响运输模式、成虫栖息地附近的滞留以及气候引起的成虫分布变化的假说。该项目将产生海洋环流和幼虫跟踪代码的模拟，其中包括作为行为线索和运输机制的波浪；这些产品将公开提供。一名研究生将写一篇相关的论文。本科生将通过美国国家科学基金会资助的REU计划、让罗格斯大学不同的本科生参与研究以提高STEM专业留存的研究、针对未被充分代表的少数族裔的罗格斯科学与工程研究计划以及斯基德莫尔暑期研究计划参与其中。示范成果将用于为本科生编写学习材料，打包成案例研究，通过国家科学案例研究教学中心分发。研究成果还将通过斯基德莫尔Encore系列讲座向成年(55岁及以上)学习者展示。波在为浮游幼虫提供直接与水平传输机制相关的行为线索方面是独一无二的，新发现的幼虫对波的反应可能会对幼虫的传输和物种分布产生反直觉的影响。两种同属蜗牛的相邻栖息地的波动气候不同：三叶草占据了波浪较小的湍急入海口和河口，而三叶草占据了波浪大得多的大陆架。这两个物种的幼虫分别感知波浪和湍流，分别作为加速度和涡度诱导的物体旋转。后期河口幼体主要表现为湍流引起的下沉，这可能会减少从进水口和河口向外的运输，而陆架幼体也表现出波浪诱导的向上游动，可以通过斯托克斯漂移帮助保持在陆架上。自20世纪60年代以来，陆架物种的活动范围已经转向更温暖的水域，这与基于耐热性的预测相反。这种转变可能是由海浪诱导的幼虫运输推动的；随着海洋变暖导致更早的产卵，幼虫将在春季遇到更大的海浪和更弱的上升流，加剧斯托克斯漂移和向内陆架更温暖、更浅的水域的岸上运输。该项目将使用数值模型来测试假设，将流动诱导的幼虫行为与运输路径、局部滞留和气候驱动的范围转移联系起来。波将分别作为行为线索和通过加速和斯托克斯漂移的平流的来源被包括在内。结果将有助于解决有关斯托克斯漂移、欧拉回流和上升流如何相互作用来运输幼虫的不确定性。数值实验将描述气候驱动的产卵物候变化如何影响幼虫的运输，潜在地确定令人困惑的陆架物种向温暖水域转移范围背后的机制。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Many bottom-dwelling marine species have larvae whose behavior in the water column impacts dispersal and adult distributions. Snail larvae swim up with more effort or sink in response to cues from waves and turbulence, and it remains unclear whether larvae can use these physical cues for retention within or navigation among habitats. Larvae that swim up under waves may be retained over the continental shelf by wave-induced shoreward drift in surface waters. However, ocean warming causes larvae to be released earlier in spring when waves are larger and coastal upwelling is weaker, potentially carrying larvae into shallower waters that exceed the adults' temperature tolerance. The investigators will use a physical model of the Middle Atlantic Bight and adjacent estuaries to test hypotheses about how waves and turbulence affect transport patterns, retention near adult habitats, and climate-induced shifts in adult distributions. The project will produce simulations of ocean circulation and larval tracking codes that include waves both as behavior cues and as a transport mechanism; these products will be made publicly available. A graduate student will do a related dissertation. Undergraduate students will be involved through an NSF-funded REU program, the Aresty Program, which engages Rutgers' diverse undergraduates in research to boost retention in STEM majors, the Rutgers Research in Science and Engineering program, which targets underrepresented minorities, and the Skidmore Summer Research program. Model outputs will be used to develop learning materials for undergraduates, packaged as a case study for distribution through the National Center for Case Study Teaching in Science. Research results will also be presented to adult (55 and over) learners through the Skidmore Encore lecture series.Waves are unique in providing planktonic larvae with a behavior cue directly tied to a horizontal transport mechanism, and newly discovered larval responses to waves could have counter-intuitive impacts on larval transport and species distributions. Wave climates differ in the adjacent habitats of two congeneric snails: Tritia obsoleta occupies turbulent inlets and estuaries where waves are small, while Tritia trivittata occupies the continental shelf where waves are much larger. These two species' larvae sense waves and turbulence separately as acceleration and vorticity-induced body rotation, respectively. Late-stage estuarine larvae mainly exhibit turbulence-induced sinking that could reduce transport out of inlets and estuaries, whereas shelf larvae also exhibit wave-induced upward swimming that could aid retention over the shelf via Stokes drift. Since the 1960s, the shelf species' range has shifted into warmer water, opposite to predictions based on thermal tolerance. This shift may be driven by wave-induced larval transport; as ocean warming induces earlier spawning, larvae will encounter larger waves and weaker upwelling in spring, intensifying Stokes drift and onshore transport toward warmer, shallower waters of the inner shelf. The project will use numerical models to test hypotheses linking flow-induced larval behaviors to transport pathways, local retention, and climate-driven range shifts. Waves will be included as a source of both behavior cues and advection through acceleration and Stokes drift, respectively. Results will help resolve uncertainties about how Stokes drift, Eulerian return flow, and upwelling interact to transport larvae. Numerical experiments will describe how climate-driven changes in spawning phenology affect larval transport, potentially identifying the mechanism behind perplexing range shifts of shelf species into warmer water.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.