Department of Biology, University of Massachusetts Boston, Boston, MA, USA.
Nicholas School for the Environment, Duke University, Durham, NC, USA.
Nat Commun. 2021 Nov 1;12(1):6290. doi: 10.1038/s41467-021-26504-4.
Invasive consumers can cause extensive ecological damage to native communities but effects on ecosystem resilience are less understood. Here, we use drone surveys, manipulative experiments, and mathematical models to show how feral hogs reduce resilience in southeastern US salt marshes by dismantling an essential marsh cordgrass-ribbed mussel mutualism. Mussels usually double plant growth and enhance marsh resilience to extreme drought but, when hogs invade, switch from being essential for plant survival to a liability; hogs selectively forage in mussel-rich areas leading to a 50% reduction in plant biomass and slower post-drought recovery rate. Hogs increase habitat fragmentation across landscapes by maintaining large, disturbed areas through trampling of cordgrass during targeted mussel consumption. Experiments and climate-disturbance recovery models show trampling alone slows marsh recovery by 3x while focused mussel predation creates marshes that may never recover from large-scale disturbances without hog eradication. Our work highlights that an invasive consumer can reshape ecosystems not just via competition and predation, but by disrupting key, positive species interactions that underlie resilience to climatic disturbances.
入侵消费者会对本地社区造成广泛的生态破坏，但对生态系统恢复力的影响知之甚少。在这里，我们使用无人机调查、操纵实验和数学模型表明，野猪如何通过破坏东南 US 盐沼中至关重要的互花米草-脊贻贝共生关系来降低盐沼的恢复力。贻贝通常可以使植物生长增加一倍，并增强盐沼对极端干旱的恢复力，但当野猪入侵时，它们会从对植物生存至关重要的角色转变为累赘；野猪会在贻贝丰富的地区进行选择性觅食，导致植物生物量减少 50%，并减缓旱后恢复速度。野猪通过踩踏互花米草来维持大型受干扰区域，从而在景观中增加栖息地碎片化。实验和气候干扰恢复模型表明，仅踩踏就会使盐沼恢复速度减缓 3 倍，而集中的贻贝捕食则会导致盐沼在没有野猪根除的情况下，可能永远无法从大规模干扰中恢复。我们的工作强调，入侵消费者不仅可以通过竞争和捕食来重塑生态系统，还可以通过破坏支持对气候干扰恢复力的关键积极物种相互作用来实现。
