Predator-prey interactions cause apparent competition between marine zooplankton groups

Area of Science:

• Marine Ecology
• Zooplankton Dynamics
• Ecosystem Interactions

Background:

• Apparent competition is an indirect interaction where shared predators affect prey species negatively.
• Quantifying indirect ecosystem effects is crucial for understanding ecosystem functioning.
• Examples of apparent competition in pelagic marine environments are scarce.

Purpose of the Study:

• To provide evidence for apparent competition between krill and copepods in the Barents Sea.
• To quantify the indirect effects mediated by planktivorous fish.
• To assess the potential impact of climate change on these interactions.

Main Methods:

• Utilized state-space statistical modeling to analyze ecological data.
• Examined the association between krill biomass and capelin survival.
• Investigated the relationship between capelin biomass and copepod biomass.

Main Results:

• Demonstrated apparent competition between dominant zooplankton groups (krill and copepods) in the Barents Sea.
• Found a positive association between krill biomass and capelin survival.
• Observed a negative association between capelin biomass and copepod biomass.

Conclusions:

• Apparent competition between krill and copepods is confirmed in the Barents Sea ecosystem.
• Projected increases in krill biomass due to climate change may negatively impact copepods.
• The study enhances projections of indirect ecosystem effects from climate change and harvesting.