Modeling the accumulation of CO2 during high density, re-circulating transport of adult Atlantic salmon, Salmo salar, from observations aboard a sea-going commercial live-haul vessel

S. Tang, H. Thorarensen, C. J. Brauner, C. M. Wood, A. P. Farrell

Research output: Contribution to journalArticle

22 Scopus citations

Abstract

A major water quality concern for salmon welfare during closed-hold transport at sea is the progressive accumulation of CO2 generated via fish respiration. Experiments showed that loads in excess of 13,000 adult Atlantic salmon, Salmo salar, being transported at an average density of 135 ± 4 kg m- 3, experienced a rapid deterioration of water quality with the partial pressure of CO2 (PCO2) increasing from 0.51 ± 0.04 mm Hg to 2.49 ± 0.38 mm Hg and water pH decreasing from 7.56 ± 0.13 to 7.23 ± 0.14 over a 30-min period of closed-hold transport. Using these data, a mathematical model was generated to establish possible transport times under various fish density and environmental conditions in closed-hold conditions. The model predicted that, if the PCO2 level was not to exceed 10 mm Hg (1 mmHg = approx. 0.133 kPa), a significantly elevated but typically sub-lethal exposure, and if the fish consumed oxygen at a routine rate measured under similar conditions, then closed-hold seawater transport could be extended to between 56 and 150 min for fish densities of 70-170 kg m- 3. If oxygen consumption rates were elevated for some reason during the transport at constant temperature, these periods would be reduced proportionately. If they occurred in conjunction with an elevation in temperature which reduces CO2 solubility, the effects are even greater. Therefore, closed-hold transport is predicted to present significant risks to fish welfare due to the rapid accumulation of CO2. Given the general inability to accurately measure CO2 levels onboard current live-haul vessels, the present model provides an important tool to minimize disturbances to fish metabolic status during closed-hold transport.

Original languageEnglish (US)
Pages (from-to)102-109
Number of pages8
JournalAquaculture
Volume296
Issue number1-2
DOIs
StatePublished - Nov 1 2009

Keywords

  • Atlantic salmon
  • CO
  • Hypercarbia
  • Live-haul transport
  • Re-circulating

ASJC Scopus subject areas

  • Aquatic Science

Fingerprint Dive into the research topics of 'Modeling the accumulation of CO<sub>2</sub> during high density, re-circulating transport of adult Atlantic salmon, Salmo salar, from observations aboard a sea-going commercial live-haul vessel'. Together they form a unique fingerprint.

  • Cite this