Noisy predator-prey model explains oscillation patterns in sockeye salmon data.

Area of Science:

• Ecology
• Population Dynamics
• Fisheries Science

Background:

• Sockeye salmon (Oncorhynchus nerka) populations exhibit complex cyclic dominance patterns.
• Understanding the drivers of these population cycles is crucial for effective fisheries management.

Purpose of the Study:

• To develop and validate a population dynamics model for sockeye salmon.
• To investigate the role of predator-prey interactions in generating cyclic dominance in sockeye salmon populations.

Main Methods:

• A sockeye salmon population dynamics model was created, incorporating predator-prey interactions, migration, and stochastic effects.
• The model's predictions were compared to Fraser River sockeye salmon spawner data.
• Wavelet transform analysis (White et al., 2014) was used to quantify cyclic dominance in time series data.

Main Results:

• The model successfully replicated oscillation patterns observed in natural sockeye salmon populations, including both persistent and intermittent cycles.
• The model incorporating predator-prey dynamics showed significantly better performance in matching persistent oscillations compared to a model without these interactions.
• Model simulations indicated that favorable fry growth conditions and strong predator coupling enhance the likelihood of persistent population oscillations.

Conclusions:

• Predator-prey dynamics are a key factor in generating persistent cyclic dominance in sockeye salmon populations.
• The developed model provides a valuable tool for understanding and predicting sockeye salmon population dynamics.
• Management strategies may benefit from considering the influence of predator-prey relationships and environmental conditions on salmon cycles.