The energetic cost of foraging explains growth anomalies in tadpoles exposed to predators

Michael J. Barry*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

7 Citations (Scopus)


Theoretical models predict that predator-induced phenotypes should have lower fitness in the absence of predators. Tadpoles frequently respond to invertebrate predators by reducing activity levels and changing their body proportions. While some studies have shown that induced defenses in tadpoles reduce growth rates, others have found no effect. The aim of this study was to measure the effects of predator presence on energy expenditure in tadpoles. Predator exposure lowered overall metabolic rate by 19%, while specific dynamic action due to food consumption increased resting metabolism by 11%. Control tadpoles moved significantly more (93.6 ± 3.9 cm/min) than predator-exposed animals (50.1 ± 7.5 cm/min), and swimming increased metabolic rate by up to 400% compared to stationary tadpoles, indicating that activity can be energetically expensive and can consume as much as 37% of assimilated energy. These findings suggest that the costs of reduced foraging are context dependent and may even be beneficial in environments where high-quality resources are closely spaced but detrimental when extensive movement is required to obtain optimal resources for growth.

Original languageEnglish
Pages (from-to)829-836
Number of pages8
JournalPhysiological and Biochemical Zoology
Issue number6
Publication statusPublished - 2014

ASJC Scopus subject areas

  • Physiology
  • Biochemistry
  • Animal Science and Zoology


Dive into the research topics of 'The energetic cost of foraging explains growth anomalies in tadpoles exposed to predators'. Together they form a unique fingerprint.

Cite this