Skip to main content

Energy allocation strategy modifies growth–survival trade-offs in juvenile fish across ecological and environmental gradients

Abstract

In young temperate zone fishes, conflicting energy demands lead to variability in growing season and winter survival. Growing season survival is driven by size-dependent predation risk whereas winter survival is constrained by autumn body size, energy storage and winter duration. We developed a model of the seasonality of energetics coupled to empirical measures of resource availability, size-dependent predation and temperature seasonality for rainbow trout (Oncorhynchus mykiss) in two sets of lakes in British Columbia, Canada, representing endpoints of a gradient of temperature, growing season duration and winter duration. This model was used to determine the energy allocation strategy which maximized first-year survival across these gradients. Survival was sensitive to the timing of the switch from somatic to storage strategies in cold, short growing season, low resource environments. A broader range of energy allocation strategies were viable in warmer, longer growing season and higher resource lakes. We used empirical observations of autumn energy storage and our modeled values for size-dependent minimal lipid levels needed to survive winter in each system to estimate winter survival for juvenile rainbow trout. Winter survival estimates were 6% in cold lakes with low resources, 82% in warm, lakes with low resources and 100% in warm lakes with high resources. Fish in warm lakes with ample resources allocated substantially more to storage than the minimum required to survive winter generated from our model, suggesting additional selection pressures for increased storage when there was ample surplus energy. We concluded that growth–survival trade-offs, modified by seasonality of the environment, influenced the growing season energy allocation strategies for young-of-the-year fish, and suggested this may be important for understanding population viability across environmental gradients.

This is a preview of subscription content, access via your institution.

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7
Fig. 8
Fig. 9

References

Download references

Acknowledgments

This research was funded by a Natural Sciences and Engineering Research Council of Canada Discovery Grant to J.R.P. S.M. was partially supported by a University of Calgary Program for the Undergraduate Research Experience (PURE) award. We also acknowledge Eric Parkinson of British Columbia Ministry of Environment and the Freshwater Fisheries Society of British Columbia for funding and access to the experimental lakes.

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Stephanie Mogensen.

Additional information

Communicated by Øyvind Fiksen.

Electronic supplementary material

Below is the link to the electronic supplementary material.

Supplementary material 1 (DOC 177 kb)

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Mogensen, S., Post, J.R. Energy allocation strategy modifies growth–survival trade-offs in juvenile fish across ecological and environmental gradients. Oecologia 168, 923–933 (2012). https://doi.org/10.1007/s00442-011-2164-0

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s00442-011-2164-0

Keywords

  • Energy allocation trade-offs
  • Lipid storage
  • Size-dependent predation
  • Survival
  • Winter starvation