阿根廷滑柔鱼能量积累的食物组成及其生态角色的研究进展

Diet composition and ecological role of Argentinean shortfin squid Illex argentinus during energy accumulation: A review

中文关键词: 阿根廷滑柔鱼  能量积累  食物组成  生态位  头足类

英文关键词: Illex argentinus  Energy accumulation  Diet composition  Ecological niche  Cephalopod

中文摘要:

      阿根廷滑柔鱼(Illex argentinus)是生长速度快、终生一次繁殖产卵、生命周期短的大洋浅海性头足类，也是世界上重要的经济物种。在西南大西洋生态系统中，阿根廷滑柔鱼发挥着重要的“生物泵”作用。在短暂的生命周期里，阿根廷滑柔鱼具有索饵–生殖洄游的生活史特征，并采取收入–资本混合型的生殖投入策略，即以现场摄食饵料吸收转化的能量投入为主、肌肉存储能量投入为辅。在不同的栖息海域与生长发育阶段，阿根廷滑柔鱼具有不同的食物组成。本文扼要概述阿根廷滑柔鱼的组织能量积累特点、能量积累过程的食物组成变化以及在西南大西洋生态系统中作为能量传输者的生态角色。同时，探讨了阿根廷滑柔鱼能量积累需求与洄游、摄食策略的关系，并对阿根廷滑柔鱼作为海洋食物网能量传输者的生态角色在气候变化、渔业活动背景下的变化做了展望分析，可为持续开发该种类资源提供资料参考。

英文摘要:

      The Argentine shortfin squid Illex argentinus is a pelagic neritic cephalopod species found in the southwest Atlantic Ocean. The squid is characterized by a short lifespan, fast growth, and semelparous reproduction. The squid is one of most important targeted species in global cephalopod fisheries and plays a key role as transient “biological pumps” in the southwest Atlantic ecosystem. The squid is a highly migratory species and can migrate hundreds or even thousands of miles between its spawning and feeding ground to complete its life cycle. The squid adopts a mixed income-capital breeding strategy, where the reproduction is mainly supported by energy acquired and mobilized rapidly during the breeding season, coupled with using energy reserves when energy demands for reproduction are robust. The squid shows spatial differences in feeding habits and also shift diets as they grow, leading to different trophic niches. In general, the squid diet shifts from crustaceans to fish and cephalopods as they mature. Given the fact that species in a higher trophic position have greater energy content, a diet shift to fish and cephalopods is expected to meet the energy demands for reproduction. In the present review, we summarized the characteristics of energy accumulated in soma and reproductive systems for I. argentinus, which shows a dramatic increase in energy in the reproductive tissues when the squid reaches maturation. In addition, we compiled previous studies that focused on diet composition and trophic roles in the southwest Atlantic ecosystem, where the squid feeds voraciously on many prey species and plays a key role as prey item for many top predators, including marine mammals. Notably, squid changes diets in relation to energy demands and resource availability. However, future research is still needed to address the functional mechanisms of the shifting dietary habits with growth. To justify the mechanism, we suggest the following priorities in the near future studies: (1) evaluate the relationships between energy acquisition and migratory habits; (2) clarify feeding strategies that potentially maximize the energy gain; and (3) address the potential effect of the ongoing global climate change and fishery activity on the role of energy transfer in the southwest Atlantic ecosystem. Such research would advance our understanding of the species and support the sustainability of resource exploitation.