Increased intrinsic growth rate is advantageous even under ecologically stressful conditions in coho salmon (Oncorhynchus kisutch)

  title={Increased intrinsic growth rate is advantageous even under ecologically stressful conditions in coho salmon (Oncorhynchus kisutch)},
  author={Liselotte Sundstr{\"o}m and Robert H. Devlin},
  journal={Evolutionary Ecology},
Growth rate is an ecologically important trait, affecting the energy acquisition from, and provisioning to, the surrounding community. One of many costs suggested to counteract the evolution of increased intrinsic growth rate is an associated reduction in tolerance to conditions of nutrient stress. Here we test this concept with individuals possessing experimentally increased intrinsic growth rates (growth hormone transgenic coho salmon, Oncorhynchus kisutch) relative to wild genotypes. Using a… 

Alternate Directed Anthropogenic Shifts in Genotype Result in Different Ecological Outcomes in Coho Salmon Oncorhynchus kisutch Fry

Domesticated and growth hormone (GH) transgenic salmon provide an interesting model to compare effects of selected versus engineered phenotypic change on relative fitness in an ecological context, and growth and survival of domesticated, transgenic, and wild-type coho salmon fry under different environmental conditions are examined.

Growth-Enhanced Transgenic Coho Salmon (Oncorhynchus kisutch) Strains Have Varied Success in Simulated Streams: Implications for Risk Assessment

The importance of determining risk estimates for each unique transgenic model independent of other models is demonstrated, with one strain having highest growth and two strains having the lowest growth in stream conditions, although all TH3 strains had consistently poor survival.

Early Life-History Consequences of Growth-Hormone Transgenesis in Rainbow Trout Reared in Stream Ecosystem Mesocosms

It is concluded that the high mortality of GH-transgenic trout during first-feeding reflects an inability to sustain the basic metabolic requirements necessary for life in complex, stream environments and is urged to caution when extrapolating the results ofGH-transgenesis risk assessment studies across multiple life-history or developmental stages.

Predation, metabolic priming and early life-history rearing environment affect the swimming capabilities of growth hormone transgenic rainbow trout

A significant genotype effect on burst-performance is found, with transgenic fish sustaining performance longer than their wild-type siblings, both in predator and predator-free stream segments, and this effect occurred before differences in growth were discernable.

Effects of domestication on parr maturity, growth, and vulnerability to predation in Atlantic salmon

Investigation of domestication-induced changes in fitness-related traits in Atlantic salmon under naturally enriched laboratory conditions with and without threat of predation suggests that domestication co-selects for predator-related stress resistance.

Importance of Experimental Environmental Conditions in Estimating Risks and Associated Uncertainty of Transgenic Fish Prior to Entry into Nature

Two experiments were designed where environmental conditions were varied to investigate the contribution of rearing density, food amount, food type, habitat complexity, and risk of predation on relative growth and survival of fast-growing transgenic and slow-growing wild-type coho salmon, showing that genotype affected growth and Survival, but genotype effects were modulated by one or more environmental factors.

Slow growth improves compensation ability: examining growth rate and starvation endurance in pit-building antlions from semi-arid and hyper-arid regions

This study demonstrates that individuals originating from different environments adopt different strategies in order to endure starvation, exemplifying antlions’ ability to compensate for mass lost during starvation.

Genetically Based Effects of Domesticated-Wild Outbreeding in Atlantic Salmon

  • P. Debes
  • Environmental Science, Biology
  • 2013
Assessing domestication-induced, genetically based changes during the parr stage by assessing growth, parr maturity and survival under predation for three salmon strains differing in their history of domestication indicates constant outbreeding effects of escapees on wild populations will increase present growth rates during all life stages and decrease early maturation probabilities for male parr and post-smolts, but by unpredictable magnitudes across hybrid generations.

Hormones as adaptive control systems in juvenile fish

An evolutionary optimization model of fish growth is presented that combines internal regulation of growth by hormone levels with the external influence of food availability and predation risk and results in different evolutionarily optimal strategies of hormone levels.




It is shown that a major shift in developmental timing can alter critical early stages affecting survival and can have a significant effect on fitness.

Competitive ability and mortality of growth-enhanced transgenic coho salmon fry and parr when foraging for food

Experimentally investigated how well transgenic salmon survive when given a choice to consume food in a predator's presence and predicted that they must also be more effective at competing for food than wild salmon and be willing to suffer higher mortality rates when foraging.

Population effects of growth hormone transgenic coho salmon depend on food availability and genotype by environment interactions.

Effects of growth hormone transgenic salmon on experimental populations were primarily mediated by an interaction between food availability and population structure, which underscores the importance of genotype by environment interactions in influencing risk assessment data for genetically modified organisms.

Adaptive Intrinsic Growth Rates: An Integration Across Taxa

  • J. Arendt
  • Economics
    The Quarterly Review of Biology
  • 1997
Empirical evidence is reviewed for costs of rapid growth, including increased fluctuating asymmetry, reduced immune capacity, and reduced ability to respond to environmental stress.

Adaptive variation in growth rate: life history costs and consequences in the speckled wood butterfly,Pararge aegeria

It is argued that for the understanding of life history variation it is necessary to consider not only the two dimensions of age and size, but also to take into full account the triangular nature of the relationship between size, time and growth rate.

Dispersal Potential is Affected by Growth‐Hormone Transgenesis in Coho Salmon (Oncorhynchus kisutch)

Results show that dispersal behavior has been affected by transgenesis and that transgenic fish therefore may venture into habitats previously not used by wild fish.

Growth hormone transgenic salmon pay for growth potential with increased predation mortality

It is shown that the predation mortality of newly hatched GH-transgenic coho salmon fry (Oncorhynchus kisutch) is much higher than in non–transgenic conspecifics, and that this difference is amplified when food abundance decreases.

Predators select against high growth rates and risk–taking behaviour in domestic trout populations

This is the first large–scale field experiment to directly test theory and simultaneously quantify the initial invasibility of domestic salmonid strains that escape into the wild from aquaculture operations, and the ecological conditions affecting their survival.


  • S. EinumI. Fleming
  • Environmental Science, Biology
    Evolution; international journal of organic evolution
  • 2000
The hypothesis that selection on juvenile traits may play an important role in the evolution of maternal traits in natural populations is supported, and egg size had fitness consequences independent of the effects of emergence time that directly affected body size at emergence and, in turn, survival and size at later life stages.