Table_2_Species Specific Responses to Grazer Cues and Acidification in Phytoplankton- Winners and Losers in a Changing World.docx

• Main Authors: Kristie Rigby, Alexandra Kinnby, Josephine Grønning, Fredrik Ryderheim, Gunnar Cervin, Emma L. Berdan, Erik Selander
• Format: Dataset
• Language: unknown
• Published: 2022
• Subjects: Oceanography; Marine Biology; Marine Geoscience; Biological Oceanography; Chemical Oceanography; Physical Oceanography; Marine Engineering; chemical defenses; chemical ecology; ocean acidification; inducible defense; plankton ecology; predator-prey interactions; pCO2; Ocean acidification; Copepods
• Online Access: https://doi.org/10.3389/fmars.2022.875858.s002; https://figshare.com/articles/dataset/Table_2_Species_Specific_Responses_to_Grazer_Cues_and_Acidification_in_Phytoplankton-_Winners_and_Losers_in_a_Changing_World_docx/19531414

Phytoplankton induce defensive traits in response to chemical alarm signals from grazing zooplankton. However, these signals are potentially vulnerable to changes in pH and it is not yet known how predator recognition may be affected by ocean acidification. We exposed four species of diatoms and one toxic dinoflagellate to future pCO 2 levels, projected by the turn of the century, in factorial combinations with predatory cues from copepods (copepodamides). We measured the change in growth, chain length, silica content, and toxin content. Effects of increased pCO 2 were highly species specific. The induction of defensive traits was accompanied by a significant reduction in growth rate in three out of five species. The reduction averaged 39% and we interpret this as an allocation cost associated with defensive traits. Copepodamides induced significant chain length reduction in three of the four diatom species. Under elevated pCO 2 Skeletonema marinoi reduced silica content by 30% and in Alexandrium minutum the toxin content was reduced by 30%. Using copepodamides to induce defensive traits in the absence of direct grazing provides a straightforward methodology to assess costs of defense in microplankton. We conclude that copepodamide signalling system is likely robust to ocean acidification. Moreover, the variable responses of different taxa to ocean acidification suggest that there will be winners and losers in a high pCO 2 world, and that ocean acidification may have structuring effects on phytoplankton communities.