Proceedings of The Physiological Society

Future Physiology (Leeds, UK) (2017) Proc Physiol Soc 39, PC68

Poster Communications

The effect of temperature on metabolic rate and within-group position in the common minnow

M. Yerli Pineda1

1. School of Biological Sciences, The University of Manchester, Manchester, United Kingdom.

Group living has a variety of costs and benefits, which are not always distributed equally among individuals within a group. Individuals toward the front of groups may have better access to food but may be more vulnerable to predation. The spatial position that individuals occupy may also be related to individual characteristics such as food demand or aerobic capacity. In swimming fish schools, individuals with higher metabolic demands or that are more efficient swimmers may be located near the front of groups. However, little is known about how environmental factors such as temperature modulate links between position within fish schools and physiological traits. Here we examine how acclimation temperature affects metabolic traits in juvenile common minnows (Phoxinus phoxinus) and in turn how this affects their positional preference within a swimming school. Sixty-three groups of 10 wild-caught minnows each were acclimated to three temperatures (16°C, 19°C, 22°C) and the positional preference (rank within the swimming school) of one focal fish per group was recorded in a swim tunnel at two different speeds (3cm s-1, 6cm s-1). Metabolic traits; standard and maximum metabolic rates (SMR, MMR) of focal individuals within each group were then estimated using intermittent flow respirometry. It was found that SMR and MMR increased at higher acclimation temperatures. Individuals with a high MMR were found at the front of schools more often. This effect was amplified at the higher speed. The results from this demonstrate the complexity in linking temperature effects with physiological and behavioural traits.

Where applicable, experiments conform with Society ethical requirements