Limited capacity for faster digestion in larval coral reef fish at an elevated temperature

McLeod, Ian M., and Clark, Timothy D. (2016) Limited capacity for faster digestion in larval coral reef fish at an elevated temperature. PLoS ONE, 11 (5). pp. 1-13.

[img]
Preview
PDF (Published Version) - Published Version
Available under License Creative Commons Attribution.

Download (704kB) | Preview
View at Publisher Website: http://dx.doi.org/10.1371/journal.pone.0...
 
2
13


Abstract

The prevalence of extreme, short-term temperature spikes in coastal regions during summer months is predicted to increase with ongoing climate change. In tropical systems, these changes are predicted to increase the metabolic demand of coral reef fish larvae while also altering the plankton communities upon which the larvae feed during their pelagic phase. The consequences of these predictions remain speculative in the absence of empirical data on the interactive effects of warm temperatures on the metabolism, postprandial processes and growth responses of coral reef fish larvae. Here, we tested the effect of increased temperature on the metabolism, postprandial performance and fine-scale growth patterns of a coral reef fish (Amphiprion percula) in the latter half of its ~11-d larval phase. First, we measured the length and weight of fed versus fasted larvae (N = 340; mean body mass 4.1±0.05 mg) across fine temporal scales at a typical current summer temperature (28.5°C) and a temperature that is likely be encountered during warm summer periods later this century (31.5°C). Second, we measured routine metabolic rate (Mo₂ (routine)) and the energetics of the postprandial processes (i.e., digestion, absorption and assimilation of a meal; termed specific dynamic action (SDA)) at both temperatures. Larvae fed voraciously when provided with food for a 12-hour period and displayed a temperature-independent increase in mass of 40.1% (28.5°C) and 42.6% (31.5°C), which was largely associated with the mass of prey in the gut. A subsequent 12-h fasting period revealed that the larvae had grown 21.2±4.8% (28.5°C) and 22.8±8.8% (31.5°C) in mass and 10.3±2.0% (28.5°C) and 7.8±2.6% (31.5°C) in length compared with pre-feeding values (no significant temperature effect). Mo₂ (routine) was 55±16% higher at 31.5°C and peak Mo₂ during the postprandial period was 28±11% higher at 31.5°C, yet elevated temperature had no significant effect on SDA (0.51±0.06 J at 28.5°C vs. 0.53±0.07 J at 31.5°C), SDA duration (6.0±0.6 h vs. 6.5±0.5 h), or the percent of total meal energy used for SDA (SDA coefficient: 10.1±1.3% vs. 13.0±1.7%). Our findings of higher Mo₂ (routine) but similar SDA coefficient at high temperature provide the first empirical evidence that coral reef fish larvae may have to secure more food to attain similar growth rates during warm summer periods, and perhaps with chronically warmer conditions associated with climate change.

Item ID: 44726
Item Type: Article (Refereed Research - C1)
Additional Information:

© 2016 McLeod, Clark. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

https://creativecommons.org/licenses/by/4.0/

ISSN: 1932-6203
Funders: James Cook University (JCU) Graduate Research Fund, Great Barrier Reef Marine Park Authority (GBRMPA) Science for Management Awards, Australian Institute of Marine Science (AIMS), Australian Institute of Marine Science at James Cook University (AIMS@JCU)
Research Data: http://dx.doi.org/10.4225/28/56DD0E93C655D
Date Deposited: 25 Jul 2016 05:22
FoR Codes: 06 BIOLOGICAL SCIENCES > 0602 Ecology > 060205 Marine and Estuarine Ecology (incl Marine Ichthyology) @ 100%
SEO Codes: 96 ENVIRONMENT > 9605 Ecosystem Assessment and Management > 960501 Ecosystem Assessment and Management at Regional or Larger Scales @ 50%
96 ENVIRONMENT > 9603 Climate and Climate Change > 960301 Climate Change Adaptation Measures @ 50%
Downloads: Total: 13
More Statistics

Actions (Repository Staff Only)

Item Control Page Item Control Page