Prochlorococcus Predation by a Globally Abundant Filter Feeder

Authors

• Carey P. Sweeney, Portland State University
• Avery Harman, Portland State University
• Anvita U. Kerkar, Portland State University
• Anne E. Aasjord, University of Bergen
• Daniel M. Chourrout, University of Bergen
• Terra Hiebert, University of Oregon
• Kelly Sutherland, University of Oregon
• Anne W. Thompson, Portland State UniversityFollow

Author ORCID Identifier(s)

Carey P. Sweeney (0000-0001-5477-5627)

Avery Harman (0009-0008-0258-6611)

Anvita U. Kerkar (000000024700029)

Anne E. Aasjord (0009-0007-1602-9093)

Daniel M. Chourrout (0000-0001-9879-6817)

Terra Hiebert (0000-0003-3220-0464)

Kelly Sutherland (0000-0001-6832-6515)

Anne W. Thompson (0000-0002-2022-9553)

Published In

Marine Ecology Progress Series

Document Type

Article

Publication Date

6-25-2026

Subjects

Prochlorococcus, Appendicularians, Picocyanobacteria, Mortality, Selection, Clearance rates; Oikopleura dioica

Abstract

Prochlorococcus is the most abundant photosynthetic cell on Earth and is critical to primary productivity and biogeochemical cycles of the open ocean. Appendicularians are ubiquitous gelatinous filter-feeding zooplankton that consume marine microorganisms including Prochlorococcus . However, the details of this trophic interaction are extremely understudied relative to their potential importance in top-down controls on Prochlorococcus . This study is the first to experimentally examine the feeding interaction between cultivated appendicularians and Prochlorococcus. We showed that Prochlorococcus ingestion rates by the appendicularian Oikopleura dioica increased with prey concentration and predator age. We revealed that appendicularians grazed equally on the 2 most globally abundant Prochlorococcus ecotypes, HLI and HLII, and that the presence of larger diatom prey did not change Prochlorococcus ingestion rates. The quantitative insight and ingestion rates provided by this study will help fill gaps in models of the marine carbon cycle and marine microbial community dynamics and biogeography and expand the knowledge of Prochlorococcus ecology.

Rights

Copyright (c) 2026 The Authors

This work is licensed under a Creative Commons Attribution 4.0 International License.

DOI

10.3354/meps15163

Persistent Identifier

https://archives.pdx.edu/ds/psu/45305

Publisher

Inter-Research Science Center

Citation Details

Sweeney, C. P., Harman, A., Kerkar, A. U., Aasjord, A. E., Chourrout, D. M., Hiebert, T., Sutherland, K., & Thompson, A. W. (2026). Prochlorococcus predation by a globally abundant filter feeder. Marine Ecology Progress Series, 788, 1–13. CLOCKSS.