Aerobic scope explains individual variation in feeding capacity.

Area of Science:

• Physiology
• Ecology
• Animal Metabolism

Background:

• Metabolic rate and aerobic scope are linked to fitness components like growth and survival.
• These associations are context-dependent, influenced by food availability.
• High standard metabolic rate (SMR) or aerobic scope (AS) may benefit organisms in resource-rich environments.

Purpose of the Study:

• To investigate the relationship between aerobic scope and food consumption in juvenile brown trout.
• To understand the mechanisms linking metabolic capacity to fitness under varying food availability.

Main Methods:

• Measured aerobic scope (AS) in juvenile brown trout (Salmo trutta).
• Quantified daily food consumption in relation to AS.
• Compared food intake between individuals with high and low AS.

Main Results:

• Juvenile brown trout with a higher AS consumed more food per day.
• Higher aerobic capacity was associated with increased food intake.
• This effect was observed in the context of food availability.

Conclusions:

• A higher aerobic scope enables greater food consumption in juvenile brown trout.
• This finding helps explain why high aerobic capacity enhances performance, such as growth rate, under high food abundance.
• Metabolic traits like AS are crucial for optimizing fitness in relation to environmental resources.