Resistance of rocky intertidal communities to oceanic climate fluctuations

RESEARCH ARTICLE Resistance of rocky intertidal communities to oceanic climate fluctuations Sarah A. GravemID*, Brittany N. Poirson¤a, Jonathan W. Robinson¤b, Bruce A. Menge Department of Integrative Biology, Partnership for Interdisciplinary Studies of Coastal Oceans (PISCO), Oregon State University, Corvallis, Oregon, United States of America ¤a Current address: Washington Department of Natural Resources, Olympia, Washington, United States of America ¤b Current address: Washington State University Snohomish County Extension, Snohomish, Washington, United States of America * GravemS@oregonstate.edu Abstract A powerful way to predict how ecological communities will respond to future climate change is to test how they have responded to the climate of the past. We used climate oscillations including the Pacific Decadal Oscillation (PDO), North Pacific Gyre Oscillation, and El Niño Southern Oscillation (ENSO) and variation in upwelling, air temperature, and sea tempera- tures to test the sensitivity of nearshore rocky intertidal communities to climate variability. Prior research shows that multiple ecological processes of key taxa (growth, recruitment, and physiology) were sensitive to environmental variation during this time frame. We also investigated the effect of the concurrent sea star wasting disease outbreak in 2013–2014. We surveyed nearly 150 taxa from 11 rocky intertidal sites in Oregon and northern California annually for up to 14-years (2006–2020) to test if community structure (i.e., the abundance

of functional groups) and diversity were sensitive to past environmental variation. We found little to no evidence that these communities were sensitive to annual variation in any of the environmental measures, and that each metric was associated with < 8.6% of yearly varia- tion in community structure. Only the years elapsed since the outbreak of sea star wasting disease had a substantial effect on community structure, but in the mid-zone only where spatially dominant mussels are a main prey of the keystone predator sea star, Pisaster ochraceus. We conclude that the established sensitivity of multiple ecological processes to annual fluctuations in climate has not yet scaled up to influence community structure. Hence, the rocky intertidal system along this coastline appears resistant to the range of oce- anic climate fluctuations that occurred during the study. However, given ongoing intensifica- tion of climate change and increasing frequencies of extreme events, future responses to climate change seem likely. Introduction Many species on Earth are sensitive to climate change [1–5]. However, the response of entire ecological communities and ecosystems to the changing climate is underexplored. PLOS ONE PLOS ONE | https://doi.org/10.1371/journal.pone.0297697 May 29, 2024 1 / 34 a1111111111 a1111111111 a1111111111 a1111111111 a1111111111 OPEN ACCESS Citation: Gravem SA, Poirson BN, Robinson JW, Menge BA (2024) Resistance of rocky intertidal communities to oceanic climate fluctuations. PLoS ONE 19(5): e0297697. https://doi.org/10.1371/ journal.pone.0297697

Editor: Vitor Hugo Rodrigues Paiva, MARE – Marine and Environmental Sciences Centre, PORTUGAL Received: June 28, 2023 Accepted: January 11, 2024 Published: May 29, 2024 Copyright: © 2024 Gravem et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Data Availability Statement: All data are publicly available at https://datadryad.org/stash/share/ TqHULHzm5D-gNHicsFv7rZjegrQ7EcgV7fyL0T4k_ fc. Funding: This work was funded by the National Science Foundation Long-Term Research in Environmental Biology (LTREB) Program (DEB10- 50694, DEB15-54702, DEB20-50017) and partially supported by funds from the David and Lucile Packard Foundation, the Andrew W. Mellon Foundation, the Wayne and Gladys Valley