School of Biological Sciences and Center for Microbial Dynamics and Infection, Georgia Institute of Technology, Atlanta, GA, USA.
Department of Microbiology and Cell Biology, Montana State University, Bozeman, MT, USA.
Nat Commun. 2024 Feb 26;15(1):1338. doi: 10.1038/s41467-024-45730-0.
Coral reefs are in global decline with coral diseases playing a significant role. This is especially true for Acroporid corals that represent ~25% of all Pacific coral species and generate much of the topographic complexity supporting reef biodiversity. Coral diseases are commonly sediment-associated and could be exacerbated by overharvest of sea cucumber detritivores that clean reef sediments and may suppress microbial pathogens as they feed. Here we show, via field manipulations in both French Polynesia and Palmyra Atoll, that historically overharvested sea cucumbers strongly suppress disease among corals in contact with benthic sediments. Sea cucumber removal increased tissue mortality of Acropora pulchra by ~370% and colony mortality by ~1500%. Additionally, farmerfish that kill Acropora pulchra bases to culture their algal gardens further suppress disease by separating corals from contact with the disease-causing sediment-functioning as mutualists rather than parasites despite killing coral bases. Historic overharvesting of sea cucumbers increases coral disease and threatens the persistence of tropical reefs. Enhancing sea cucumbers may enhance reef resilience by suppressing disease.
珊瑚礁在全球范围内不断减少，珊瑚疾病在其中起着重要作用。尤其是对于占太平洋所有珊瑚物种约 25%的鹿角珊瑚来说，情况更是如此，它们为支持珊瑚生物多样性的大部分地形复杂性提供了基础。珊瑚疾病通常与沉积物有关，而过度捕捞海参等食泥动物可能会加剧这种情况，因为食泥动物会清理珊瑚礁沉积物，并在进食时抑制微生物病原体。通过在法属波利尼西亚和帕尔米拉环礁的实地实验，我们发现，历史上过度捕捞的海参强烈抑制了与海底沉积物接触的珊瑚的疾病。海参的移除使鹿角珊瑚的组织死亡率增加了约 370%，群体死亡率增加了约 1500%。此外，以杀死鹿角珊瑚基部来养殖藻类园的农民鱼进一步抑制了疾病，因为它们将珊瑚与致病沉积物隔离开来，尽管杀死了珊瑚基部，但它们作为共生体而不是寄生虫发挥了作用。历史上过度捕捞海参会增加珊瑚疾病的发生，并威胁热带珊瑚礁的生存。增加海参的数量可能会通过抑制疾病来增强珊瑚礁的恢复力。
