CSS-Inc., Fairfax, VA, United States of America.
Nicholas School of the Environment, Duke University Marine Lab, Beaufort, NC, United States of America.
PLoS One. 2020 Sep 2;15(9):e0237374. doi: 10.1371/journal.pone.0237374. eCollection 2020.
Large predators play important ecological roles, yet many are disproportionately imperiled. In marine systems, artificial reefs are often deployed to restore degraded reefs or supplement existing reefs, but it remains unknown whether these interventions benefit large predators. Comparative field surveys of thirty artificial and natural reefs across ~200 km of the North Carolina, USA coast revealed large reef-associated predators were more dense on artificial than natural reefs. This pattern was associated with higher densities of transient predators (e.g. jacks, mackerel, barracuda, sharks) on artificial reefs, but not of resident predators (e.g., grouper, snapper). Further analyses revealed that this pattern of higher transient predator densities on artificial reefs related to reef morphology, as artificial reefs composed of ships hosted higher transient predator densities than concrete reefs. The strength of the positive association between artificial reefs and transient predators increased with a fundamental habitat trait-vertical extent. Taller artificial reefs had higher densities of transient predators, even when accounting for habitat area. A global literature review of high trophic level fishes on artificial and natural habitats suggests that the overall pattern of more predators on artificial habitats is generalizable. Together, these findings provide evidence that artificial habitats, especially those like sunken ships that provide high vertical structure, may support large predators.
大型掠食者在生态系统中发挥着重要作用，但许多大型掠食者的生存却受到了不成比例的威胁。在海洋系统中，人工礁石经常被用来修复退化的珊瑚礁或补充现有的珊瑚礁，但目前尚不清楚这些干预措施是否有利于大型掠食者。本研究在北卡罗来纳州约 200 公里的海域范围内，对 30 个人工礁石和自然礁石进行了比较实地调查，结果表明，与自然礁石相比，大型礁栖掠食者在人工礁石上的密度更高。这种模式与人工礁石上瞬态掠食者（如鲹鱼、鲭鱼、梭鱼、鲨鱼）的密度更高有关，但与定居掠食者（如石斑鱼、笛鲷）无关。进一步的分析表明，这种人工礁石上瞬态掠食者密度较高的模式与礁石形态有关，因为由船只组成的人工礁石比混凝土礁石上瞬态掠食者的密度更高。人工礁石与瞬态掠食者之间的正相关强度随着基本栖息地特征——垂直延伸度的增加而增加。即使考虑到栖息地面积，较高的人工礁石也有更高密度的瞬态掠食者。对人工和自然栖息地高营养级鱼类的全球文献综述表明，更多的掠食者出现在人工栖息地的总体模式是普遍存在的。综上所述，这些发现为人工栖息地（特别是那些提供高垂直结构的沉船）可能支持大型掠食者提供了证据。
