Data from: An exotic species alters patterns of marine community development

Predictions of ecological patterns can be strengthened through replication of foundational studies under different environmental conditions to evaluate the consistency in their underlying processes. In this study, we replicated Sutherland and Karlson’s 1977 classic ecology study that tested terrestrial paradigms of community development in a marine fouling community. The abundance patterns of marine fouling species were quantified on sequentially submerged settlement plates to investigate the effects of disturbance date on short- and long-term patterns of community development, and the original study’s datasets were re-analyzed for comparison. In both studies, community structure was initially shaped by disturbance date due to monthly and annual variation in larval recruitment; however, the influence of disturbance date diminished over time. Despite these similarities, the underlying drivers of long-term patterns of community development have shifted substantially since the 1970’s. During the present study, an exotic tunicate, Clavelina oblonga, dominated plates over time and its dominance was associated with significant declines in species diversity. In contrast, the 1970s long-term community was characterized by a heterogeneous mixture of species that varied inter-annually, yielding increased species diversity over time. Continued observations of our settlement plates (2 years total) indicated that C. oblonga remains the dominant species in this community, suggesting that these findings are not the result of a single, novel recruitment event. These results highlight how an exotic species can alter patterns of community development and biodiversity. Moreover, this study demonstrates the need to replicate foundational ecological studies to evaluate community dynamics and underlying processes in light of ongoing ecosystem change.

通过在不同环境条件下重复开展基础性生态学研究，可强化对生态格局的预测能力，以此评估其背后调控过程的一致性。本研究重复了Sutherland与Karlson于1977年开展的经典生态学研究——该研究曾在海洋污损生物群落中验证群落构建的陆地范式。研究团队通过依次投放的定植附着板对海洋污损物种的丰度格局进行量化，以探究干扰日期对群落构建短期与长期格局的影响；同时重新分析原始研究的数据集以作对照。两项研究均显示，由于幼体补充存在月际与年际差异，群落结构最初受干扰日期的调控；但随着时间推移，干扰日期的影响逐渐减弱。尽管存在上述相似性，但自20世纪70年代以来，群落构建长期格局的核心驱动因素已发生显著变化。本研究期间，一种外来被囊动物——长体海鞘（Clavelina oblonga）随时间推移成为附着板上的优势类群，其优势地位与物种多样性的显著下降密切相关。与之形成对比的是，20世纪70年代的长期群落以年际间存在差异的异质物种种群组合为特征，其物种多样性随时间推移逐渐提升。对附着板的持续观测（总时长2年）显示，长体海鞘（C. oblonga）仍是该群落的优势物种，表明本研究结果并非由单次突发的幼体补充事件所致。上述研究结果揭示了外来物种如何改变群落构建格局与生物多样性。此外，本研究表明，鉴于生态系统正持续发生变化，需重复开展基础性生态学研究以评估群落动态及其背后的调控过程。