Temperature-related variation in growth rate, size, maturation and life span in a marine herbivorous fish over a latitudinal gradient
Article first published online: 10 DEC 2013
© 2013 The Authors. Journal of Animal Ecology © 2013 British Ecological Society
Journal of Animal Ecology
Volume 83, Issue 4, pages 866–875, July 2014
How to Cite
L. Trip, E. D., Clements, K. D., Raubenheimer, D., Choat, J. H. (2014), Temperature-related variation in growth rate, size, maturation and life span in a marine herbivorous fish over a latitudinal gradient. Journal of Animal Ecology, 83: 866–875. doi: 10.1111/1365-2656.12183
- Issue published online: 16 JUN 2014
- Article first published online: 10 DEC 2013
- Accepted manuscript online: 19 NOV 2013 08:12AM EST
- Manuscript Accepted: 13 NOV 2013
- Manuscript Received: 16 JAN 2013
- Royal Society of New Zealand Marsden
- University of Auckland International Fees Bursary
- University of Auckland's School of Biological Sciences
- University of Auckland Performance Based Research Fund
- National Research Centre for Growth and Development
- Berrigan-Charnov life-history puzzle;
- marine ectotherm life-history traits;
- smooth-joining two-phase growth model
- In ectotherms, growth rate, body size and maturation rate covary with temperature, with the direction and magnitude of variation predicted by the Temperature-Size Rule (TSR). Nutritional quality or availability of food, however, may vary over latitudinal gradients, resulting in ambiguous effects on body size and maturation rate. The Temperature-Constraint Hypothesis (TCH) predicts that marine herbivorous ectotherms are nutritionally compromised at latitudes exceeding 30°. This provides an opportunity to resolve the contrasting demographic responses of ectotherms to variation in temperature and nutritional status over latitudinal gradients.
- This study uses analysis of demographic rates to evaluate the predictions of the TSR in a marine herbivorous ectotherm sampled over a significant latitudinal gradient.
- The direction and magnitude of demographic variation was established in the marine herbivorous fish, Odax pullus (the butterfish), and compared with that of a phylogenetically related but trophically distinct species, the carnivorous Notolabrus fucicola (the banded wrasse). Both species were sampled at three locations across the length of New Zealand covering latitudes between 35°S and 49°S. Growth rate, mean size-at-age, age- and size-at-maturity, life span and abundance were estimated for each species at each location.
- Demographic traits of both taxa varied with latitude. Both species showed slower initial growth rates, and matured later at a larger body size at higher latitudes than populations sampled at lower latitudes. In addition, abundances increased significantly at higher latitudes in both species.
- These results were consistent with the TSR but not with the TCH, confirming that nutritional ecology (herbivore vs. carnivory) did not determine demographic patterns over a biologically significant latitudinal gradient. Results from this study suggest that the absence of herbivorous reef fishes from the higher latitudes of the Northern Hemisphere may not reflect a general physiological mechanism as suggested by the TCH and highlights the need to clarify the evolutionary histories of the marine biota of each hemisphere.