TY - JOUR

T1 - Shifting seagrass‐oyster interactions alter species response to ocean warming and acidification

AU - DuBois, Katherine

AU - Baumann, Justin H.

AU - Charles, Eban J.

AU - Ralph, Fiona G.

AU - Carlon, David B.

PY - 2024/11/1

Y1 - 2024/11/1

N2 - A major challenge in biodiversity research is the incorporation of species interac-tions into frameworks describing population and community response to globaledfnmental change (GEC). Mutualisms are a type of species interaction especiallysensitive to changing environmental conditions, and the breakdown of facilitativespecies interactions could amplify the negative impacts of novel climate regimeson focal species.2. Here, we investigate how reciprocal interactions between two coastal founda-tion species, the eastern oyster (Crassostrea virginica) and eelgrass (Zostera marina)shift in sign and magnitude in response to ocean warming (+1.5°C) and acidifica-tion (−0.4 pH) via a manipulative co-culture experiment in mesocosms.3. Under ambient environmental conditions, oysters facilitated eelgrass leaf growthand clonal reproduction by 35% and 38%, respectively. Simultaneously, eelgrassdecreased the oyster condition index (the ratio of tissue to shell biomass) by 35%,indicating greater allocation of energy to shell growth instead of soft tissues atambient conditions. Varying sensitivities of each species to ocean warming and/or acidification treatments led to complex shifts in species interactions that weretrait dependent. As such, community outcomes under future conditions were in-fluenced by species interactions that amplified and mitigated species response toenvironmental change.4. Synthesis: Given that species interaction effect sizes were similar in magnitudeto effect sizes of warming or pH treatments, our results underscore the need toidentify key species and interaction types that strongly influence community re-sponse to GEC. Specifically, for macrophyte-bivalve interactions, understandinghow physiological limitations on growth are impacted by environmental hetero-geneity and co-culture will support the successful restoration of natural popula-tions and the rapid expansion of aquaculture.

AB - A major challenge in biodiversity research is the incorporation of species interac-tions into frameworks describing population and community response to globaledfnmental change (GEC). Mutualisms are a type of species interaction especiallysensitive to changing environmental conditions, and the breakdown of facilitativespecies interactions could amplify the negative impacts of novel climate regimeson focal species.2. Here, we investigate how reciprocal interactions between two coastal founda-tion species, the eastern oyster (Crassostrea virginica) and eelgrass (Zostera marina)shift in sign and magnitude in response to ocean warming (+1.5°C) and acidifica-tion (−0.4 pH) via a manipulative co-culture experiment in mesocosms.3. Under ambient environmental conditions, oysters facilitated eelgrass leaf growthand clonal reproduction by 35% and 38%, respectively. Simultaneously, eelgrassdecreased the oyster condition index (the ratio of tissue to shell biomass) by 35%,indicating greater allocation of energy to shell growth instead of soft tissues atambient conditions. Varying sensitivities of each species to ocean warming and/or acidification treatments led to complex shifts in species interactions that weretrait dependent. As such, community outcomes under future conditions were in-fluenced by species interactions that amplified and mitigated species response toenvironmental change.4. Synthesis: Given that species interaction effect sizes were similar in magnitudeto effect sizes of warming or pH treatments, our results underscore the need toidentify key species and interaction types that strongly influence community re-sponse to GEC. Specifically, for macrophyte-bivalve interactions, understandinghow physiological limitations on growth are impacted by environmental hetero-geneity and co-culture will support the successful restoration of natural popula-tions and the rapid expansion of aquaculture.

U2 - 10.1111/1365-2745.14406

DO - 10.1111/1365-2745.14406

M3 - Article

VL - 112

SP - 2552

EP - 2566

JO - Journal of Ecology

JF - Journal of Ecology

SN - 0022-0477

IS - 11

ER -