Physiological plasticity to water flow habitat in the damselfish, Acanthochromis polyacanthus: linking phenotype to performance

PLoS One. 2015 Mar 25;10(3):e0121983. doi: 10.1371/journal.pone.0121983. eCollection 2015.

Abstract

The relationships among animal form, function and performance are complex, and vary across environments. Therefore, it can be difficult to identify morphological and/or physiological traits responsible for enhancing performance in a given habitat. In fishes, differences in swimming performance across water flow gradients are related to morphological variation among and within species. However, physiological traits related to performance have been less well studied. We experimentally reared juvenile damselfish, Acanthochromis polyacanthus, under different water flow regimes to test 1) whether aspects of swimming physiology and morphology show plastic responses to water flow, 2) whether trait divergence correlates with swimming performance and 3) whether flow environment relates to performance differences observed in wild fish. We found that maximum metabolic rate, aerobic scope and blood haematocrit were higher in wave-reared fish compared to fish reared in low water flow. However, pectoral fin shape, which tends to correlate with sustained swimming performance, did not differ between rearing treatments or collection sites. Maximum metabolic rate was the best overall predictor of individual swimming performance; fin shape and fish total length were 3.3 and 3.7 times less likely than maximum metabolic rate to explain differences in critical swimming speed. Performance differences induced in fish reared in different flow environments were less pronounced than in wild fish but similar in direction. Our results suggest that exposure to water motion induces plastic physiological changes which enhance swimming performance in A. polyacanthus. Thus, functional relationships between fish morphology and performance across flow habitats should also consider differences in physiology.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adaptation, Physiological / physiology*
  • Animals
  • Ecosystem*
  • Environment*
  • Perciformes / physiology*
  • Phenotype*
  • Swimming / physiology*

Associated data

  • figshare/10.6084/M9.FIGSHARE.923561

Grants and funding

This study was funded by The Australian Research Council Centre of Excellence for Coral Reef Studies, The Australian National University, The Natural Sciences and Engineering Research Council of Canada, The Australian Society for Fish Biology, The Society for Integrative and Comparative Biology, The Great Barrier Reef Marine Park Authority, Total Diving in Montréal and an Ian Potter Doctoral Fellowship at Lizard Island (Lizard Island Research Station, a facility of the Australian Museum). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.