Collaborative Research: Hypoxia and the ecology, behavior and physiology of jumbo squid, Dosidicus gigas

“该奖项的资金来源是《2009 年美国复苏和再投资法案》（公法 111-5）。”该项目涉及 Dosidicus gigas 的生态生理学，这是一种东太平洋特有的大型鱿鱼，栖息在公海和大陆架环境中。需要解决的问题包括： 1) 巨蜥对 OML 的利用在日常和季节上有何变化，以及 OML 及其相关动物群的垂直分布如何变化？ 2）OML中发现的条件会损害鱿鱼的哪些行为，以及如何补偿损害以最大限度地降低利用该环境的成本？ 3）鱿鱼在低氧条件下保持如此显着水平的游泳活动的生理和生化过程是什么？研究人员将使用涉及海洋学、声学、电子标记、生理和生化方法的综合方法。巨型鱿鱼在小型中层水生物和顶级脊椎动物捕食者之间提供了营养联系，而近地表水域和深层低氧环境（OML）之间的日常垂直迁移是成年鱿鱼的正常行为特征。电子标签显示，这种鱿鱼可以在上层 OML 寒冷、缺氧的条件下长时间保持活跃。实验室研究表明，在寒冷、缺氧的挑战下，有氧代谢受到抑制，但无氧代谢似乎并不能解释维持活动水平的原因。在野外利用 OML 可以允许白天在中层水域生物中觅食。夜间也会在地表附近觅食，因此多西迪库斯可能能够连续进食。 D. gigas 全年都存在于瓜伊马斯盆地的不同地区，这使得鱿鱼分布的变化与不同时间尺度上海洋学特征的变化有关。这项研究引起了广泛的兴趣，因为在过去十年中，Dosidicus gigas 大大扩展了其范围，并且有报道称，它在加利福尼亚和智利附近的入侵地区以具有重要商业价值的鱼类为食。此外，OML在过去几十年中一直在扩大，主要是通过浅滩垂直扩大，包括阿拉斯加湾、南加州湾和热带海洋的几个富产区，并且几乎肯定会伴随着OML的变化而产生各种生态影响。此外，巨型鱿鱼目前支持着世界上最大的鱿鱼渔业，这项研究将为可靠的生物量估计提供声学方法，对墨西哥和其他地方的渔业管理具有影响。一个相关的目标是与墨西哥的同事合作制定鱿鱼渔业管理计划。之前的工作涉及与墨西哥同事的合作，包括为两国的本科生、研究生和博士后提供培训和研究机会。它还涉及通过电视、印刷品和网络媒体进行的公共宣传工作。这种魅力十足的物种提供了将气候变化与生态影响联系起来的绝佳手段，外展活动将继续围绕这一主题。一项新的国际努力将在墨西哥南下加利福尼亚州圣罗莎莉亚的实地工作现场建立一个鱿鱼研究实验室。该设施将让墨西哥大学生参与海洋研究并实施当地教育计划。

"This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5)." This project concerns the ecological physiology of Dosidicus gigas, a large squid endemic to the eastern Pacific where it inhabits both open ocean and continental shelf environments. Questions to be addressed include: 1) How does utilization of the OML by D. gigas vary on both a daily and seasonal basis, and how do the vertical distributions of the OML and its associated fauna vary? 2)What behaviors of squid are impaired by conditions found in the OML, and how are impairments compensated to minimize costs of utilizing this environment? and 3)What are the physiological and biochemical processes by which squid maintain swimming activity at such remarkable levels under low oxygen conditions? The investigators will use an integrated approach involving oceanographic, acoustic, electronic tagging, physiological and biochemical methods. D. gigas provides a trophic connection between small, midwater organisms and top vertebrate predators, and daily vertical migrations between near-surface waters and a deep, low-oxygen environment (OML) characterize normal behavior of adult squid. Electronic tagging has shown that this squid can remain active for extended periods in the cold, hypoxic conditions of the upper OML. Laboratory studies have demonstrated suppression of aerobic metabolism during a cold, hypoxic challenge, but anaerobic metabolism does not appear to account for the level of activity maintained. Utilization of the OML in the wild may permit daytime foraging on midwater organisms. Foraging also occurs near the surface at night, and Dosidicus may thus be able to feed continuously. D. gigas is present in different regions of the Guaymas Basin on a predicable year-round basis, allowing changes in squid distribution to be related to changing oceanographic features on a variety time scales.This research is of broad interest because Dosidicus gigas has substantially extended its range over the last decade, and foraging on commercially important finfish in invaded areas off California and Chile has been reported. In addition, the OML has expanded during the last several decades, mostly vertically by shoaling, including in the Gulf of Alaska, the Southern California Bight and several productive regions of tropical oceans, and a variety of ecological impacts will almost certainly accompany changes in the OML. Moreover, D. gigas currently supports the world's largest squid fishery, and this study will provide acoustic methods for reliable biomass estimates, with implications for fisheries management in Mexico and elsewhere. A related goal is to work with colleagues in Mexico on a squid fishery management plan. Previous work involved collaboration with Mexican colleagues, including training and research opportunities for undergraduate, graduate and postdoctoral students from both nations. It also involved public outreach efforts through television, print and web media. This charismatic species provides an excellent means to connect climate change with ecological effects, and outreach activities will continue with this theme. A new international effort will establish a laboratory for research on squid at the site of field work in Santa Rosalia, Baja California Sur, Mexico. The facility will involve Mexican college students in marine research and implement local educational programs.