Centro de Investigación para la Conservación de los Ecosistemas Australes (ICEA), Punta Arenas, Chile.
Pristine Seas, National Geographic Society, Washington, DC, United States of America.
PLoS One. 2021 Sep 20;16(9):e0257662. doi: 10.1371/journal.pone.0257662. eCollection 2021.
Knowledge of the ecology of the fish fauna associated with kelp (primarily Macrocystis pyrifera) forests in Southern Patagonia is scarce, especially in how abiotic and biotic variables influence their structure, diversity, and distribution. This information is important for the management and conservation of this unique ecosystem, which has minimal anthropogenic impacts at present. We analyzed data from 122 quantitative underwater transects conducted within kelp forests at 61 stations from Chile's southern Patagonian fjords to the Cape Horn and Diego Ramirez archipelagos and the southern tip of Argentina, including the Mitre Peninsula and Isla de los Estados. In total, 25 fish species belonging to 13 families were observed. Multivariate analysis indicated that there are significant differences in fish assemblage structure among locations and wave exposures, which was driven primarily by Patagonotothen sima and Paranotothenia magellanica, which occurred on exposed and semi-exposed stations. P. cornucola was mainly distributed across sheltered stations of the Kawésqar National Park. Temperature, salinity, depth, and kelp density influenced fish assemblage structure, with the highest diversity in areas with the lowest temperature and greater depth at Isla de los Estados. In contrast, species richness, diversity, abundance, and biomass were all lower in areas with high density of the understory kelp Lessonia spp., which might be driven by the absence of P. tessellata, P. squamiceps and P. cornucola, the most important species in terms of occurrence, abundance, and biomass. Our study provides the first broad-scale description of the fish assemblages associated with kelp forests along the southern cone of South America based on non-invasive visual transects, improving our knowledge of the distribution of fish assemblages across several environmental conditions in this vast and little-studied area.
有关与南巴塔哥尼亚巨型海藻（主要是 Macrocystis pyrifera）森林相关的鱼类动物群的生态学知识相对较少，特别是在非生物和生物变量如何影响其结构、多样性和分布方面。这些信息对于管理和保护这个目前受人为影响最小的独特生态系统非常重要。我们分析了在智利南部巴塔哥尼亚峡湾至合恩角和迪亚哥·拉米雷斯群岛以及阿根廷最南端（包括米特雷半岛和火地岛）的 61 个站点的 122 个定量水下横切线上获得的数据。总共观察到属于 13 个科的 25 种鱼类。多元分析表明，鱼类群落结构在地点和波曝露之间存在显著差异，这主要是由 Patagonotothen sima 和 Paranotothenia magellanica 驱动的，它们出现在暴露和半暴露的站点上。P. cornucola 主要分布在 Kawésqar 国家公园的遮蔽站。温度、盐度、深度和巨藻密度影响鱼类群落结构，在火地岛的温度最低和深度最大的区域多样性最高。相比之下，在密度较高的亚层巨藻 Lessonia spp. 的区域，物种丰富度、多样性、丰度和生物量都较低，这可能是由于 P. tessellata、P. squamiceps 和 P. cornucola 的缺失所致，这些物种在发生、丰度和生物量方面都非常重要。我们的研究首次基于非侵入性视觉横切提供了有关南锥体南美洲巨型海藻森林相关鱼类群落的广泛描述，提高了我们对这一广阔且研究甚少的区域内鱼类群落在多个环境条件下分布的认识。
