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Blanchard TS, Earhart ML, Shatsky AK, Schulte PM. Intraspecific variation in thermal performance curves for early development in Fundulus heteroclitus. JOURNAL OF EXPERIMENTAL ZOOLOGY. PART A, ECOLOGICAL AND INTEGRATIVE PHYSIOLOGY 2024. [PMID: 38769744 DOI: 10.1002/jez.2827] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2023] [Revised: 04/04/2024] [Accepted: 05/06/2024] [Indexed: 05/22/2024]
Abstract
Thermal performance curves (TPCs) provide a framework for understanding the effects of temperature on ectotherm performance and fitness. TPCs are often used to test hypotheses regarding local adaptation to temperature or to develop predictions for how organisms will respond to climate warming. However, for aquatic organisms such as fishes, most TPCs have been estimated for adult life stages, and little is known about the shape of TPCs or the potential for thermal adaptation at sensitive embryonic life stages. To examine how latitudinal gradients shape TPCs at early life stages in fishes, we used two populations of Fundulus heteroclitus that have been shown to exhibit latitudinal variation along the thermal cline as adults. We exposed embryos from both northern and southern populations and their reciprocal crosses to eight different temperatures (15°C, 18°C, 21°C, 24°C, 27°C, 30°C, 33°C, and 36°C) until hatch and examined the effects of developmental temperature on embryonic and larval traits (shape of TPCs, heart rate, and body size). We found that the pure southern embryos had a right-shifted TPC (higher thermal optimum (Topt) for developmental rate, survival, and embryonic growth rate) whereas pure northern embryos had a vertically shifted TPC (higher maximum performance (Pmax) for developmental rate). Differences across larval traits and cross-type were also found, such that northern crosses hatched faster and hatched at a smaller size compared to the pure southern population. Overall, these observed differences in embryonic and larval traits are consistent with patterns of both local adaptation and countergradient variation.
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Affiliation(s)
- Tessa S Blanchard
- Department of Zoology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Madison L Earhart
- Department of Zoology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Ariel K Shatsky
- Department of Zoology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Patricia M Schulte
- Department of Zoology, University of British Columbia, Vancouver, British Columbia, Canada
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2
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Thomas P, Peele EE, Yopak KE, Sulikowski JA, Kinsey ST. Lectin binding to pectoral fin of neonate little skates reared under ambient and projected-end-of-century temperature regimes. J Morphol 2024; 285:e21698. [PMID: 38669130 PMCID: PMC11064730 DOI: 10.1002/jmor.21698] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2023] [Revised: 04/03/2024] [Accepted: 04/12/2024] [Indexed: 04/28/2024]
Abstract
The glycosylation of macromolecules can vary both among tissue structural components and by adverse conditions, potentially providing an alternative marker of stress in organisms. Lectins are proteins that bind carbohydrate moieties and lectin histochemistry is a common method to visualize microstructures in biological specimens and diagnose pathophysiological states in human tissues known to alter glycan profiles. However, this technique is not commonly used to assess broad-spectrum changes in cellular glycosylation in response to environmental stressors. In addition, the binding of various lectins has not been studied in elasmobranchs (sharks, skates, and rays). We surveyed the binding tissue structure specificity of 14 plant-derived lectins, using both immunoblotting and immunofluorescence, in the pectoral fins of neonate little skates (Leucoraja erinacea). Skates were reared under present-day or elevated (+5°C above ambient) temperature regimes and evaluated for lectin binding as an indicator of changing cellular glycosylation and tissue structure. Lectin labeling was highly tissue and microstructure specific. Dot blots revealed no significant changes in lectin binding between temperature regimes. In addition, lectins only detected in the elevated temperature treatment were Canavalia ensiformis lectin (Concanavalin A) in spindle cells of muscle and Ricinus communis agglutinin in muscle capillaries. These results provide a reference for lectin labeling in elasmobranch tissue that may aid future investigations.
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Affiliation(s)
- Peyton Thomas
- Department of Biology and Marine Biology, University of North Carolina at Wilmington, Wilmington, NC, 28403, USA
| | - Emily E. Peele
- Department of Biology and Marine Biology, University of North Carolina at Wilmington, Wilmington, NC, 28403, USA
| | - Kara E. Yopak
- Department of Biology and Marine Biology, University of North Carolina at Wilmington, Wilmington, NC, 28403, USA
| | - James A. Sulikowski
- 2030 SE Marine Science Drive, Coastal Oregon Marine Experiment Station, Oregon State University, Corvallis, OR 97365, USA
| | - Stephen T. Kinsey
- Department of Biology and Marine Biology, University of North Carolina at Wilmington, Wilmington, NC, 28403, USA
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Navarro JM, Cárdenas L, Ortiz A, Figueroa Á, Morley SA, Vargas-Chacoff L, Leclerc JC, Détrée C. Testing the physiological capacity of the mussel Mytilus chilensis to establish into the Southern Ocean. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 921:170941. [PMID: 38360303 DOI: 10.1016/j.scitotenv.2024.170941] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2023] [Revised: 02/01/2024] [Accepted: 02/10/2024] [Indexed: 02/17/2024]
Abstract
The Southern Ocean and the Antarctic Circumpolar Current create environmental conditions that serve as an efficient barrier to prevent the colonization of non-native species (NNS) in the marine ecosystems of Antarctica. However, warming of the Southern Ocean and the increasing number of transport opportunities are reducing the physiological and physical barriers, increasing the chances of NNS arriving. The aim of this study was to determine the limits of survival of the juvenile mussels, M. chilensis, under current Antarctic conditions and those projected under climate change. These assessments were used to define the mussels potential for establishment in the Antarctic region. Experimental mussels were exposed to four treatments: -1.5 °C (Antarctic winter), 2 °C (Antarctic summer), 4 °C (Antarctic projected) and 8 °C (control) for 80 days and a combination of physiological and transcriptomics approaches were used to investigate mussel response. The molecular responses of mussels were congruent with the physiological results, revealing tolerance to Antarctic winter temperatures. However, a higher number of regulated differentially expressed gene (DEGs) were reported in mussels exposed to Antarctic winter temperatures (-1.5 °C). This tolerance was associated with the activation of the biological processes associated with apoptosis (up regulated) and both cell division and cilium assembly (down regulated). The reduced feeding rate and the negative scope for growth, for a large part of the exposure period at -1.5 °C, suggests that Antarctic winter temperatures represents an environmental barrier to M. chilensis from the Magellanic region settling in the Antarctic. Although M. chilensis are not robust to current Antarctica thermal conditions, future warming scenarios are likely to weaken these physiological barriers. These results strongly suggest that the West Antarctic Peninsula could become part of Mytilus distributional range, especially with dispersal aided by increasing maritime transport activity across the Southern Ocean.
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Affiliation(s)
- Jorge M Navarro
- Instituto de Ciencias Marinas y Limnológicas, Facultad de Ciencias, Universidad Austral de Chile, Valdivia, Chile; Centro FONDAP de Investigación en Dinámica de Ecosistemas Marinos de Altas Latitudes (IDEAL), Punta Arenas, Chile.
| | - Leyla Cárdenas
- Instituto de Ciencias Ambientales y Evolutivas, Facultad de Ciencias, Universidad Austral de Chile, Valdivia, Chile
| | - Alejandro Ortiz
- Centro FONDAP de Investigación en Dinámica de Ecosistemas Marinos de Altas Latitudes (IDEAL), Punta Arenas, Chile
| | - Álvaro Figueroa
- Instituto de Ciencias Ambientales y Evolutivas, Facultad de Ciencias, Universidad Austral de Chile, Valdivia, Chile
| | - Simon A Morley
- British Antarctic Survey, Natural Environment Research Council, Cambridge, United Kingdom
| | - Luis Vargas-Chacoff
- Instituto de Ciencias Marinas y Limnológicas, Facultad de Ciencias, Universidad Austral de Chile, Valdivia, Chile; Centro FONDAP de Investigación en Dinámica de Ecosistemas Marinos de Altas Latitudes (IDEAL), Punta Arenas, Chile; Millenium Institute Biodiversity of Antarctic and Subantarctic Ecosystems, BASE, Universidad Austral d Chile, Valdivia, Chile
| | - Jean-Charles Leclerc
- Sorbonne Université, CNRS, UMR 7144 AD2M, Station Biologique de Roscoff, Place Georges Teissier, 29680 Roscoff, France
| | - Camille Détrée
- Laboratoire de Biologie des Organismes et Ecosystèmes Aquatiques (BOREA) Université de Caen-Normandie, CREC marine station, 54 rue du Docteur Charcot, 14530 Luc-sur-mer, France
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Earls KN, Campbell JB, Rinehart JP, Greenlee KJ. Effects of temperature on metabolic rate during metamorphosis in the alfalfa leafcutting bee. Biol Open 2023; 12:bio060213. [PMID: 38156711 PMCID: PMC10805150 DOI: 10.1242/bio.060213] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2023] [Accepted: 11/15/2023] [Indexed: 01/03/2024] Open
Abstract
Spring conditions, especially in temperate regions, may fluctuate abruptly and drastically. Environmental variability can expose organisms to temperatures outside of their optimal thermal ranges. For ectotherms, sudden changes in temperature may cause short- and long-term physiological effects, including changes in respiration, morphology, and reproduction. Exposure to variable temperatures during active development, which is likely to occur for insects developing in spring, can cause detrimental effects. Using the alfalfa leafcutting bee, Megachile rotundata, we aimed to determine if oxygen consumption could be measured using a new system and to test the hypothesis that female and male M. rotundata have a thermal performance curve with a wide optimal range. Oxygen consumption of M. rotundata pupae was measured across a large range of temperatures (6-48°C) using an optical oxygen sensor in a closed respirometry system. Absolute and mass-specific metabolic rates were calculated and compared between bees that were extracted from their brood cells and those remaining in the brood cell to determine whether pupae could be accurately measured inside their brood cells. The metabolic response to temperature was non-linear, which is an assumption of a thermal performance curve; however, the predicted negative slope at higher temperatures was not observed. Despite sexual dimorphism in body mass, sex differences only occurred in mass-specific metabolic rates. Higher metabolic rates in males may be attributed to faster development times, which could explain why there were no differences in absolute metabolic rate measurements. Understanding the physiological and ecological effects of thermal environmental variability on M. rotundata will help to better predict their response to climate change.
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Affiliation(s)
- Kayla N. Earls
- Department of Biological Sciences, North Dakota State University, Fargo, ND 58108, USA
| | - Jacob B. Campbell
- Department of Biological Sciences, North Dakota State University, Fargo, ND 58108, USA
| | - Joseph P. Rinehart
- Edward T. Schafer Agricultural Research Center, US Department of Agriculture/Agricultural Research Station, Fargo, ND 58102,USA
| | - Kendra J. Greenlee
- Department of Biological Sciences, North Dakota State University, Fargo, ND 58108, USA
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McKenzie DJ, Zhang Y, Eliason EJ, Schulte PM, Claireaux G, Blasco FR, Nati JJH, Farrell AP. Intraspecific variation in tolerance of warming in fishes. JOURNAL OF FISH BIOLOGY 2021; 98:1536-1555. [PMID: 33216368 DOI: 10.1111/jfb.14620] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Revised: 10/09/2020] [Accepted: 11/17/2020] [Indexed: 05/12/2023]
Abstract
Intraspecific variation in key traits such as tolerance of warming can have profound effects on ecological and evolutionary processes, notably responses to climate change. The empirical evidence for three primary elements of intraspecific variation in tolerance of warming in fishes is reviewed. The first is purely mechanistic that tolerance varies across life stages and as fishes become mature. The limited evidence indicates strongly that this is the case, possibly because of universal physiological principles. The second is intraspecific variation that is because of phenotypic plasticity, also a mechanistic phenomenon that buffers individuals' sensitivity to negative impacts of global warming in their lifetime, or to some extent through epigenetic effects over successive generations. Although the evidence for plasticity in tolerance to warming is extensive, more work is required to understand underlying mechanisms and to reveal whether there are general patterns. The third element is intraspecific variation based on heritable genetic differences in tolerance, which underlies local adaptation and may define long-term adaptability of a species in the face of ongoing global change. There is clear evidence of local adaptation and some evidence of heritability of tolerance to warming, but the knowledge base is limited with detailed information for only a few model or emblematic species. There is also strong evidence of structured variation in tolerance of warming within species, which may have ecological and evolutionary significance irrespective of whether it reflects plasticity or adaptation. Although the overwhelming consensus is that having broader intraspecific variation in tolerance should reduce species vulnerability to impacts of global warming, there are no sufficient data on fishes to provide insights into particular mechanisms by which this may occur.
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Affiliation(s)
- David J McKenzie
- MARBEC, University of Montpellier, CNRS, IFREMER, IRD, Montpellier, France
| | - Yangfan Zhang
- Department of Zoology, University of British Columbia, Vancouver, British Columbia, Canada
| | | | - Patricia M Schulte
- Department of Zoology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Guy Claireaux
- Université de Bretagne Occidentale, LEMAR (UMR 6539), Centre Ifremer de Bretagne, Plouzané, France
| | - Felipe R Blasco
- Department of Physiological Sciences, Federal University of São Carlos, São Carlos, Brazil
- Joint Graduate Program in Physiological Sciences, Federal University of São Carlos - UFSCar/São Paulo State University, UNESP Campus Araraquara, Araraquara, Brazil
| | - Julie J H Nati
- MARBEC, University of Montpellier, CNRS, IFREMER, IRD, Montpellier, France
| | - Anthony P Farrell
- Department of Zoology, University of British Columbia, Vancouver, British Columbia, Canada
- Faculty of Land and Food Systems, University of British Columbia, Vancouver, British Columbia, Canada
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Del Rio AM, Mukai GN, Martin BT, Johnson RC, Fangue NA, Israel JA, Todgham AE. Differential sensitivity to warming and hypoxia during development and long-term effects of developmental exposure in early life stage Chinook salmon. CONSERVATION PHYSIOLOGY 2021; 9:coab054. [PMID: 34257996 PMCID: PMC8271147 DOI: 10.1093/conphys/coab054] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 04/28/2021] [Accepted: 06/15/2021] [Indexed: 05/13/2023]
Abstract
Warming and hypoxia are two stressors commonly found within natural salmon redds that are likely to co-occur. Warming and hypoxia can interact physiologically, but their combined effects during fish development remain poorly studied, particularly stage-specific effects and potential carry-over effects. To test the impacts of warm water temperature and hypoxia as individual and combined developmental stressors, late fall-run Chinook salmon embryos were reared in 10 treatments from fertilization through hatching with two temperatures [10°C (ambient) and 14°C (warm)], two dissolved oxygen saturation levels [normoxia (100% air saturation, 10.4-11.4 mg O2/l) and hypoxia (50% saturation, 5.5 mg O2/l)] and three exposure times (early [eyed stage], late [silver-eyed stage] and chronic [fertilization through hatching]). After hatching, all treatments were transferred to control conditions (10°C and 100% air saturation) through the fry stage. To study stage-specific effects of stressor exposure we measured routine metabolic rate (RMR) at two embryonic stages, hatching success and growth. To evaluate carry-over effects, where conditions during one life stage influence performance in a later stage, RMR of all treatments was measured in control conditions at two post-hatch stages and acute stress tolerance was measured at the fry stage. We found evidence of stage-specific effects of both stressors during exposure and carry-over effects on physiological performance. Both individual stressors affected RMR, growth and developmental rate while multiple stressors late in development reduced hatching success. RMR post-hatch showed persistent effects of embryonic stressor exposure that may underlie differences observed in developmental timing and acute stress tolerance. The responses to stressors that varied by stage during development suggest that stage-specific management efforts could support salmon embryo survival. The persistent carry-over effects also indicate that considering sub-lethal effects of developmental stressor exposure may be important to understanding how climate change influences the performance of salmon across life stages.
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Affiliation(s)
- Annelise M Del Rio
- Department of Animal Science, University of California Davis, Davis, CA 95616, USA
| | - Gabriella N Mukai
- Department of Animal Science, University of California Davis, Davis, CA 95616, USA
- Department of Biology, University of Hawai’i at Mānoa, Honolulu, HI 96822, USA
| | - Benjamin T Martin
- University of California Santa Cruz, Cooperative Institute for Marine Ecosystems and Climate (CIMEC), Santa Cruz, CA 95064, USA
- Southwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, 110 Shaffer Road, Santa Cruz, CA 95060, USA
- Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, 1098 XH Amsterdam, the Netherlands
| | - Rachel C Johnson
- Department of Animal Science, University of California Davis, Davis, CA 95616, USA
- University of California Santa Cruz, Cooperative Institute for Marine Ecosystems and Climate (CIMEC), Santa Cruz, CA 95064, USA
- Southwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, 110 Shaffer Road, Santa Cruz, CA 95060, USA
| | - Nann A Fangue
- Department of Wildlife, Fish, and Conservation Biology, University of California Davis, Davis, CA 95616, USA
| | - Joshua A Israel
- Bay-Delta Office, U.S. Bureau of Reclamation, Sacramento, CA 95825, USA
| | - Anne E Todgham
- Department of Animal Science, University of California Davis, Davis, CA 95616, USA
- Corresponding author: Department of Animal Science, University of California Davis, Davis, CA 95616, USA.
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Schwemmer TG, Baumann H, Murray CS, Molina AI, Nye JA. Acidification and hypoxia interactively affect metabolism in embryos, but not larvae, of the coastal forage fish Menidia menidia. J Exp Biol 2020; 223:jeb228015. [PMID: 33046569 DOI: 10.1242/jeb.228015] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Accepted: 10/05/2020] [Indexed: 11/20/2022]
Abstract
Ocean acidification is occurring in conjunction with warming and deoxygenation as a result of anthropogenic greenhouse gas emissions. Multistressor experiments are critically needed to better understand the sensitivity of marine organisms to these concurrent changes. Growth and survival responses to acidification have been documented for many marine species, but studies that explore underlying physiological mechanisms of carbon dioxide (CO2) sensitivity are less common. We investigated oxygen consumption rates as proxies for metabolic responses in embryos and newly hatched larvae of an estuarine forage fish (Atlantic silverside, Menidia menidia) to factorial combinations of CO2×temperature or CO2×oxygen. Metabolic rates of embryos and larvae significantly increased with temperature, but partial pressure of CO2 (PCO2 ) alone did not affect metabolic rates in any experiment. However, there was a significant interaction between PCO2 and partial pressure of oxygen (PO2 ) in embryos, because metabolic rates were unaffected by PO2 level at ambient PCO2 , but decreased with declining PO2 under elevated PCO2 For larvae, however, PCO2 and PO2 had no significant effect on metabolic rates. Our findings suggest high individual variability in metabolic responses to high PCO2 , perhaps owing to parental effects and time of spawning. We conclude that early life metabolism is largely resilient to elevated PCO2 in this species, but that acidification likely influences energetic responses and thus vulnerability to hypoxia.
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Affiliation(s)
- T G Schwemmer
- School of Marine and Atmospheric Sciences, Stony Brook University, Stony Brook, NY 11794, USA
| | - H Baumann
- Department of Marine Sciences, University of Connecticut Avery Point, 1080 Shennecossett Road, Groton, CT 06340, USA
| | - C S Murray
- Washington Ocean Acidification Center, School of Marine and Environmental Affairs, University of Washington, 3710 Brooklyn Ave NE, Seattle, WA 98105, USA
| | - A I Molina
- School of Marine and Atmospheric Sciences, Stony Brook University, Stony Brook, NY 11794, USA
| | - J A Nye
- School of Marine and Atmospheric Sciences, Stony Brook University, Stony Brook, NY 11794, USA
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Toward controlled breeding of the blackfin icefish Chaenocephalus aceratus (Lönnberg 1906): determination of spermatozoa concentration and evaluation of short- and long-term preservation of semen. Polar Biol 2020. [DOI: 10.1007/s00300-020-02729-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Illing B, Downie A, Beghin M, Rummer J. Critical thermal maxima of early life stages of three tropical fishes: Effects of rearing temperature and experimental heating rate. J Therm Biol 2020; 90:102582. [DOI: 10.1016/j.jtherbio.2020.102582] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Revised: 03/20/2020] [Accepted: 03/31/2020] [Indexed: 01/26/2023]
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Mascaró M, Horta JL, Diaz F, Paschke K, Rosas C, Simões N. Effect of a gradually increasing temperature on the behavioural and physiological response of juvenile Hippocampus erectus: Thermal preference, tolerance, energy balance and growth. J Therm Biol 2019; 85:102406. [PMID: 31657747 DOI: 10.1016/j.jtherbio.2019.102406] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2019] [Revised: 08/13/2019] [Accepted: 08/25/2019] [Indexed: 12/17/2022]
Abstract
The physiological and behavioural responses of ectotherms to temperature is strongly dependent on the individuals' previous thermal history. Laboratory based studies investigating the mechanisms of thermoregulation in marine ectotherms, however, rarely consider key temporal elements of thermal exposure, such as the rate at which temperature changes. We tested the hypothesis that juvenile seahorses, Hippocampus erectus, from a tropical coastal lagoon in Yucatan, Mexico, would exhibit variations in physiological and behavioural descriptors of thermoregulation when submitted to contrasting regimes during 30 days: temperature constant at 25 °C (C 25); gradually increasing 1 °C every 5 days from 25 to 30 °C (GI 25-30); and constant at 30 °C (C 30). Immediately after exposure, critical maximum temperature, thermal preference, oxygen consumption, partial energy balance, growth rate and survival of seahorses were measured. Seahorses exposed to GI 25-30 showed a significantly higher critical thermal maxima (37.8 ± 0.9 °C), preference (28.7 ± 0.4 °C), growth (1.10 ± 0.49%) and survival (97.6%) than those exposed to C 30 (36.5 ± 1, 29.4 ± 0.3 °C, 0.48 ± 0.32%, 73.8%, respectively). Both high temperature regimes induced metabolic depression, but ramping resulted in a greater amount of energy assimilated (278.9 ± 175.4 J g-1 day-1) and higher energy efficiency for growth (89.8%) than constant exposure to 30 °C (115.4 ± 63.4 J g-1 day-1, 65.3%, respectively). Gradually increasing temperature allowed physiological mechanisms of thermal adjustment to take place, reflecting the capacity of juvenile H. erectus to respond to environmental change. Despite its advantage, this capacity is limited in time, since the cumulative effect of thermal exposure affected metabolic performance, eventually compromising survival. The study of seahorse response to thermal variations in the context of ocean warming needs to consider the temporal elements of thermal exposure to foresee its vulnerability under future scenarios.
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Affiliation(s)
- M Mascaró
- Unidad Multidisciplinaria de Docencia e Investigación, Facultad de Ciencias, Universidad Nacional Autónoma de México, Puerto de abrigo s/n Sisal, Yucatán, Mexico; Laboratorio Nacional de Resiliencia Costera Laboratorios Nacionales, CONACYT, Mexico City, Mexico
| | - J L Horta
- Posgrado en Ciencias del Mar y Limnología, Facultad de Ciencias, Universidad Nacional Autónoma de México, Puerto de abrigo s/n Sisal, Yucatán, Mexico
| | - F Diaz
- Laboratorio de Ecofisiología de Organismos Acuáticos, Departamento de Biotecnología Marina, Centro de Investigación Científica y de Educación Superior de Ensenada (CICESE), Carretera Ensenada-Tijuana # 3918, Ensenada, Baja California, Mexico
| | - K Paschke
- Instituto de Acuicultura, Universidad Austral de Chile, Los Pinos s/n Balneario Pelluco, Puerto Montt, Chile
| | - C Rosas
- Unidad Multidisciplinaria de Docencia e Investigación, Facultad de Ciencias, Universidad Nacional Autónoma de México, Puerto de abrigo s/n Sisal, Yucatán, Mexico; Laboratorio Nacional de Resiliencia Costera Laboratorios Nacionales, CONACYT, Mexico City, Mexico
| | - N Simões
- Unidad Multidisciplinaria de Docencia e Investigación, Facultad de Ciencias, Universidad Nacional Autónoma de México, Puerto de abrigo s/n Sisal, Yucatán, Mexico; Laboratorio Nacional de Resiliencia Costera Laboratorios Nacionales, CONACYT, Mexico City, Mexico; International Chair for Coastal and Marine Studies, Harte Research Institute for Gulf of Mexico Studies, Texas A&M University, Corpus Christi, Texas, USA.
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