King Abdullah University of Science and Technology, Red Sea Research Center, Thuwal, 23955-6900, Saudi Arabia.
King Abdullah University of Science and Technology, Red Sea Research Center, Thuwal, 23955-6900, Saudi Arabia; Carl von Ossietzky University Oldenburg, Institute for Chemistry and Biology of the Marine Environment (ICBM), Wilhelmshaven, Germany.
Mar Environ Res. 2023 Mar;185:105884. doi: 10.1016/j.marenvres.2023.105884. Epub 2023 Jan 20.
Macroalgae canopies are common in tropical coastlines, and can be feeding grounds for coral reef fishes. We investigated whether fish transfer algal material from Sargassum-dominated macroalgae habitats to coral reefs by collecting gut contents of two herbivorous fish species (Naso elegans and N. unicornis) from coral reefs in the central Red Sea. On inshore reefs close to macroalgae canopies, Sargassum accounted for up to 41% of these species' gut contents while almost no Sargassum was found in the stomachs of fish on offshore reefs farther from macroalgae canopies. Using consumption and excretion rates from literature, we estimate that these fish consume up to 6.0 mmol C/m reef/day and excrete up to 10.8 μmol N/m reef/day and 1.0 μmol P/m reef/day across inshore reefs as a result of Sargassum consumption. Examining fish-mediated connections between habitats illuminates the role of fish as a vector of nutrition to nutrient-poor coral reefs.
大型藻类林在热带海岸线很常见，也是珊瑚礁鱼类的觅食地。我们通过收集红海中部珊瑚礁两种草食性鱼类（Naso elegans 和 N. unicornis）的肠道内容物，研究了鱼类是否会将藻类物质从以马尾藻为主的大型藻类生境转移到珊瑚礁。在靠近大型藻类林的近岸礁，马尾藻占这些鱼类肠道内容物的比例高达 41%，而在远离大型藻类林的外礁的鱼类胃中几乎没有发现马尾藻。根据文献中的消耗和排泄率，我们估计这些鱼类由于食用马尾藻，每天每平方米礁可消耗高达 6.0 mmol C，排泄高达 10.8 μmol N 和 1.0 μmol P。通过检查鱼类在生境之间的介导联系，揭示了鱼类作为营养物质载体向营养贫瘠的珊瑚礁输送营养的作用。
