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

“这项奖励是根据2009年美国复苏和再投资法案（公法111-5）资助的。”这个项目关注的是Dosidicus gigas的生态生理学，这是一种东太平洋特有的大型鱿鱼，它生活在开阔的海洋和大陆架环境中。需要解决的问题包括：1)巨鳉对表层资源的利用在日常和季节基础上是如何变化的，表层资源及其相关动物群的垂直分布是如何变化的？2)在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小化利用该环境的成本？3)在低氧条件下，乌贼通过什么生理生化过程保持如此高水平的游泳活动？调查人员将采用综合方法，包括海洋学、声学、电子标签、生理和生化方法。D. gigas提供了小型、中水生物和顶级脊椎动物捕食者之间的营养联系，并且在近地表水域和深、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。电子标记显示，这种鱿鱼可以在上表层的寒冷、缺氧条件下长时间保持活跃。实验室研究表明，在寒冷、缺氧的环境下，有氧代谢受到抑制，但无氧代谢似乎不能解释维持的活动水平。在野外利用OML可以在白天觅食中水生物。觅食也发生在夜间的地表附近，因此Dosidicus可能能够连续进食。在可预测的全年基础上，D. gigas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各种时间尺度上海洋特征的变化有关。这项研究引起了广泛的兴趣，因为在过去的十年里，土sidicus gigas已经大大扩展了它的活动范围，并且在加利福尼亚和智利的入侵地区觅食重要的商业鱼类。此外，在过去的几十年里，OML已经扩展，主要是通过浅水区垂直扩展，包括在阿拉斯加湾，南加州湾和热带海洋的几个生产区域，各种生态影响几乎肯定会伴随着OML的变化。此外，D. gigas目前支持世界上最大的鱿鱼渔业，这项研究将为可靠的生物量估算提供声学方法，对墨西哥和其他地方的渔业管理具有重要意义。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，包括为来自两国的本科生、研究生和博士后提供培训和研究机会。它还包括通过电视、印刷和网络媒体进行的公众宣传工作。这种极具魅力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，并将继续开展这一主题的推广活动。一项新的国际努力将在墨西哥下加利福尼亚州南部圣罗莎利亚的实地工作地点建立一个研究鱿鱼的实验室。该设施将让墨西哥大学生参与海洋研究，并实施当地的教育项目。

"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.