Vision-mediated influence of low oxygen on the physiology and ecology of marine larvae

由于海洋变暖和陆地营养物质的输入，全世界海洋中的氧气正在流失。视力需要大量的氧气，当氧气供应不足时，视力可能不那么有效或需要更多的光线。这对于具有复杂眼睛和视觉能力的活跃海洋动物尤其如此，包括活跃的节肢动物（螃蟹），头足类动物（鱿鱼）和鱼类。随着水深的增加，加州沿海沃茨的氧气和光照急剧下降。该项目研究了年轻（幼虫）高度视觉海洋动物的视觉生理学和生态学如何对氧气损失做出反应，重点是关键的渔业和水产养殖物种。实验和观察将检验这一假设，即氧气压力将改变这些生物有效观察所需的光线，影响它们可以生活和生存的水深。该项目将为学生和早期职业科学家提供跨学科的经验，并告知公众（通过在斯克里普斯海洋学研究所伯奇水族馆的外联活动）与决策者讨论海洋中氧气减少的影响。氧气损失对视力的负面影响已被描述为人类和其他陆地生物，但从未在海洋环境中，尽管海洋中的氧气随着深度和时间的推移会发生很大的变化，而且视觉系统的代谢需求很高。本项目将通过3种眼睛设计和光传导机制的组合来测试低氧对视觉的影响：具有横纹肌光感受器的复眼（节肢动物），具有横纹肌光感受器的单眼（头足动物）和具有纤毛光感受器的单眼（鱼类）。将对每组的代表性分类群进行一系列氧气和光线控制的实验室实验，包括金枪鱼蟹，Pleuroncodes planipes;市场鱿鱼，Doryteuthis opalescens和白色海鲈鱼，Aprotoscion nobilis。体内电生理学和行为趋光性实验将确定新的氧指标的视觉生理和功能，并将在呼吸实验中确定的代谢阈值进行比较。水文数据收集超过30年的CalCOFI计划在南加州湾将进行评估方面的视觉和代谢的限制，以确定在每个物种的关键luminoxyscape（范围内的氧气和光条件所需的视觉生理和功能的目标物种）边界的氧气变化的后果。这三个基于视觉的功能组的发现可以测试氧气限制的视觉反应是否为低氧下高度视觉的远洋类群中物种分布的变浅提供了额外的解释，并将有助于集中未来的研究工作，更好地了解造成栖息地压缩的压力因素，以及海洋中氧气损失的扩大。该奖项反映了NSF的法定使命，并被认为值得支持通过使用基金会的知识价值和更广泛的影响审查标准进行评估。

Oxygen is being lost in the ocean worldwide as a result of ocean warming and the input of nutrients from land. Vision requires a large amount of oxygen, and may be less effective or require more light when oxygen is in short supply. This is especially true for active marine animals with complex eyes and visual capabilities, including active arthropods (crabs), cephalopods (squid), and fish. The California coastal waters exhibit a sharp drop in oxygen and light with increasing water depth. This project examines how visual physiology and ecology in young (larval) highly visual marine animals respond to oxygen loss, with a focus on key fisheries and aquaculture species. Experiments and observations will test the hypothesis that oxygen stress will change the light required for these organisms to see effectively, influencing the water depths where they can live and survive. The project will provide interdisciplinary experiences to students and an early career scientist and inform both the public (through outreach at the Birch Aquarium at Scripps Institution of Oceanography) and policy makers about the effects of oxygen decline in the ocean.Negative effects of oxygen loss on vision have been described for humans and other terrestrial organisms, but never in the marine environment, despite the large changes in oxygen that can occur with depth and over time in the ocean, and the high metabolic demand of visual systems. This project will test the effects of low oxygen on vision in 3 combinations of eye design and photo-transduction mechanisms: compound eye with rhabdomeric photoreceptors (arthropods), simple eye with rhabdomeric photoreceptors (cephalopods), and simple eye with ciliary photoreceptors (fish). A series of oxygen- and light-controlled laboratory experiments will be conducted on representative taxa of each group including the tuna crab, Pleuroncodes planipes; the market squid, Doryteuthis opalescens, and the white sea bass, Atractoscion nobilis. In vivo electrophysiology and behavioral phototaxis experiments will identify new oxygen metrics for visual physiology and function, and will be compared to metabolic thresholds determined in respiration experiments. Hydrographic data collected over 3 decades by the CalCOFI program in the Southern California Bight will be evaluated with respect to visual and metabolic limits to determine the consequences of oxygen variation on the critical luminoxyscape (range of oxygen and light conditions required for visual physiology and function in target species) boundary in each species. Findings for the three vision-based functional groups may test whether oxygen-limited visual responses offer an additional explanation for the shoaling of species distributions among highly visual pelagic taxa in low oxygen, and will help to focus future research efforts and better understand the stressors contributing to habitat compression with expanding oxygen loss in the ocean.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.