Castorani, Max C. N.Bell, Tom W.Walter, Jonathan A.Reuman, Daniel C.Cavanaugh, Kyle C.Sheppard, Lawrence W.2023-02-142023-02-142022-06-30Castorani, M. C. N., Bell, T. W., Walter, J. A., Reuman, D. C., Cavanaugh, K. C., & Sheppard, L. W. (2022). Disturbance and nutrients synchronise kelp forests across scales through interacting Moran effects. Ecology letters, 25(8), 1854–1868. https://doi.org/10.1111/ele.14066https://hdl.handle.net/1808/33792Spatial synchrony is a ubiquitous and important feature of population dynamics, but many aspects of this phenomenon are not well understood. In particular, it is largely unknown how multiple environmental drivers interact to determine synchrony via Moran effects, and how these impacts vary across spatial and temporal scales. Using new wavelet statistical techniques, we characterised synchrony in populations of giant kelp Macrocystis pyrifera, a widely distributed marine foundation species, and related synchrony to variation in oceanographic conditions across 33 years (1987–2019) and >900 km of coastline in California, USA. We discovered that disturbance (storm-driven waves) and resources (seawater nutrients)—underpinned by climatic variability—act individually and interactively to produce synchrony in giant kelp across geography and timescales. Our findings demonstrate that understanding and predicting synchrony, and thus the regional stability of populations, relies on resolving the synergistic and antagonistic Moran effects of multiple environmental drivers acting on different timescales.© 2022 The Authors. Ecology Letters published by John Wiley & Sons Ltd. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.http://creativecommons.org/licenses/by/4.0/CoherenceDisturbanceMoran effectNitrateNorth Pacific Gyre OscillationOceanographyPopulation dynamicsRemote sensingSpatial synchronyWavelet transformsArticle10.1111/ele.14066https://orcid.org/0000-0002-7372-9359https://orcid.org/0000-0002-0173-2866https://orcid.org/0000-0003-2983-751Xhttps://orcid.org/0000-0002-1407-8947https://orcid.org/0000-0002-9032-2059PMC9541195openAccess