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Infective prey leads to a partial role reversal in a predator-prey interaction
Veijo Kaitala1, Mikko Koivu-Jolma2, Jouni Laakso1
1Organismal and Evolutionary Biology Research Programme, Faculty of Biological and Environmental Sciences, Helsinki University, Helsinki, Finland.
Plos One
|September 17, 2021
Summary
This study models predator-prey dynamics where prey infects predators. Findings show infective prey can thrive, even exceeding carrying capacity, altering population balances and extinction risks.
Area of Science:
- Ecology
- Population Dynamics
- Microbial Ecology
Background:
- Traditional predator-prey models assume predator consumes prey.
- An infective prey can infect, kill, and consume its predator, creating a unique interaction.
- This interaction allows prey to utilize predators as a resource for growth.
Purpose of the Study:
- To model the population dynamics of a predator-prey system with partial role reversal.
- To analyze the impact of infectivity and grazing rates on species population sizes.
- To investigate conditions leading to the extinction of either species.
Main Methods:
- Development of a population dynamics model.
- Analysis of the interaction between the sea cucumber Apostichopus japonicus (predator) and Vibrio splendidus (infective prey).
- Simulation of varying infectivity and grazing rates to observe population changes.
Main Results:
- Relative population sizes of sea cucumber and V. splendidus can switch with increasing infectivity.
- Infective prey (V. splendidus) can benefit from predator presence, exceeding its carrying capacity.
- Prey extinction occurs with low growth rate or no infectivity; predator extinction is linked to high prey infectivity or abundant moderately infective prey.
Conclusions:
- Partial role reversal in predator-prey interactions is a significant phenomenon.
- The dynamics of infective prey can lead to unexpected population outcomes, including exceeding carrying capacity.
- Understanding these dynamics is crucial for predicting species survival and ecosystem stability.
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