Thermal physiology of juvenile red roman seabream, Chrysoblephus laticeps after long-term exposure to low pH conditions
Climate change has caused a combination of effects on the physiology of fishes. Of particular concern are the effects of thermal variability and ocean acidification. Organismal energy budgets change throughout ontogeny and research into the metabolic scope during early life stages is particularly us...
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ftrhodesunivcory:vital:72143 2024-09-15T18:28:04+00:00 Thermal physiology of juvenile red roman seabream, Chrysoblephus laticeps after long-term exposure to low pH conditions Allison, Caitlin 2023-10-13 computer online resource application/pdf 1 online resource (141 pages) pdf http://hdl.handle.net/10962/424323 https://corycommons.ru.ac.za/vital/access/manager/Repository/vital:72143 English eng Rhodes University Faculty of Science, Ichthyology and Fisheries Science http://hdl.handle.net/10962/424323 vital:72143 https://corycommons.ru.ac.za/vital/access/manager/Repository/vital:72143 Allison, Caitlin Use of this resource is governed by the terms and conditions of the Creative Commons "Attribution-NonCommercial-ShareAlike" License (http://creativecommons.org/licenses/by-nc-sa/2.0/) Climatic changes Ocean acidification Basal metabolism Chrysoblephus laticeps Thermal tolerance (Physiology) Phenotypic plasticity Fishes Climatic factors Academic theses Master's theses text 2023 ftrhodesunivcory 2024-07-10T23:32:50Z Climate change has caused a combination of effects on the physiology of fishes. Of particular concern are the effects of thermal variability and ocean acidification. Organismal energy budgets change throughout ontogeny and research into the metabolic scope during early life stages is particularly useful in identifying potential bottlenecks. The first part of this thesis aimed to assess the absolute aerobic scope (AAS, described as the difference between the maximum and standard metabolic rates) of individual juveniles from a protected population of the endemic, commercially important seabream, Chrysoblephus laticeps, across a range of ecologically relevant temperatures (T = 11, 14, 18, 22˚C) under present-day conditions (pH = 8.03, pCO2 ≈ 420 μatm) using intermittent flow respirometry. The second component sought to investigate how long-term exposure (from fertilisation to juvenile, ~100 days exposure) to high-pCO2/hypercapnic conditions (pH = 7.63, pCO2 ≈ 1400 μatm), would affect the AAS of juvenile C. laticeps over a range of temperatures. Lower pH conditions were predicted to cause a decrease in the AAS of treatment animals due to additional energetic costs of acid-base regulation. The findings of the first data chapter demonstrated that juvenile C. laticeps reared under current CO2 conditions are tolerant to a wide range of thermal conditions, and individuals with a broad aerobic scope will be the best suited to coping with enhanced thermal variability. In contrast to the expected outcomes of the second data chapter, juvenile C. laticeps reared under high pCO2 conditions displayed greater AAS at high and low temperatures when compared with specimens from high pH conditions. Whilst a high degree of individual phenotypic variation was observed in the metabolic response of both groups, this was reduced at the lower and upper extreme temperatures for high pH and low pH animals respectively. Notably, the variation in treatment animal’s SMR was significantly diminished across all temperatures tested, compared to ... Master Thesis Ocean acidification Rhodes University Cory: Repository |
institution |
Open Polar |
collection |
Rhodes University Cory: Repository |
op_collection_id |
ftrhodesunivcory |
language |
English |
topic |
Climatic changes Ocean acidification Basal metabolism Chrysoblephus laticeps Thermal tolerance (Physiology) Phenotypic plasticity Fishes Climatic factors |
spellingShingle |
Climatic changes Ocean acidification Basal metabolism Chrysoblephus laticeps Thermal tolerance (Physiology) Phenotypic plasticity Fishes Climatic factors Allison, Caitlin Thermal physiology of juvenile red roman seabream, Chrysoblephus laticeps after long-term exposure to low pH conditions |
topic_facet |
Climatic changes Ocean acidification Basal metabolism Chrysoblephus laticeps Thermal tolerance (Physiology) Phenotypic plasticity Fishes Climatic factors |
description |
Climate change has caused a combination of effects on the physiology of fishes. Of particular concern are the effects of thermal variability and ocean acidification. Organismal energy budgets change throughout ontogeny and research into the metabolic scope during early life stages is particularly useful in identifying potential bottlenecks. The first part of this thesis aimed to assess the absolute aerobic scope (AAS, described as the difference between the maximum and standard metabolic rates) of individual juveniles from a protected population of the endemic, commercially important seabream, Chrysoblephus laticeps, across a range of ecologically relevant temperatures (T = 11, 14, 18, 22˚C) under present-day conditions (pH = 8.03, pCO2 ≈ 420 μatm) using intermittent flow respirometry. The second component sought to investigate how long-term exposure (from fertilisation to juvenile, ~100 days exposure) to high-pCO2/hypercapnic conditions (pH = 7.63, pCO2 ≈ 1400 μatm), would affect the AAS of juvenile C. laticeps over a range of temperatures. Lower pH conditions were predicted to cause a decrease in the AAS of treatment animals due to additional energetic costs of acid-base regulation. The findings of the first data chapter demonstrated that juvenile C. laticeps reared under current CO2 conditions are tolerant to a wide range of thermal conditions, and individuals with a broad aerobic scope will be the best suited to coping with enhanced thermal variability. In contrast to the expected outcomes of the second data chapter, juvenile C. laticeps reared under high pCO2 conditions displayed greater AAS at high and low temperatures when compared with specimens from high pH conditions. Whilst a high degree of individual phenotypic variation was observed in the metabolic response of both groups, this was reduced at the lower and upper extreme temperatures for high pH and low pH animals respectively. Notably, the variation in treatment animal’s SMR was significantly diminished across all temperatures tested, compared to ... |
format |
Master Thesis |
author |
Allison, Caitlin |
author_facet |
Allison, Caitlin |
author_sort |
Allison, Caitlin |
title |
Thermal physiology of juvenile red roman seabream, Chrysoblephus laticeps after long-term exposure to low pH conditions |
title_short |
Thermal physiology of juvenile red roman seabream, Chrysoblephus laticeps after long-term exposure to low pH conditions |
title_full |
Thermal physiology of juvenile red roman seabream, Chrysoblephus laticeps after long-term exposure to low pH conditions |
title_fullStr |
Thermal physiology of juvenile red roman seabream, Chrysoblephus laticeps after long-term exposure to low pH conditions |
title_full_unstemmed |
Thermal physiology of juvenile red roman seabream, Chrysoblephus laticeps after long-term exposure to low pH conditions |
title_sort |
thermal physiology of juvenile red roman seabream, chrysoblephus laticeps after long-term exposure to low ph conditions |
publisher |
Rhodes University |
publishDate |
2023 |
url |
http://hdl.handle.net/10962/424323 https://corycommons.ru.ac.za/vital/access/manager/Repository/vital:72143 |
genre |
Ocean acidification |
genre_facet |
Ocean acidification |
op_relation |
http://hdl.handle.net/10962/424323 vital:72143 https://corycommons.ru.ac.za/vital/access/manager/Repository/vital:72143 |
op_rights |
Allison, Caitlin Use of this resource is governed by the terms and conditions of the Creative Commons "Attribution-NonCommercial-ShareAlike" License (http://creativecommons.org/licenses/by-nc-sa/2.0/) |
_version_ |
1810469369822576640 |