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Verhille CE, MacDonald M, Noble B, Demorest G, Roche A, Frazier K, Albertson LK. Thermal tolerance of giant salmonfly nymphs ( Pteronarcys californica) varies across populations in a regulated river. CONSERVATION PHYSIOLOGY 2024; 12:coae043. [PMID: 38974500 PMCID: PMC11225080 DOI: 10.1093/conphys/coae043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Revised: 05/24/2024] [Accepted: 06/10/2024] [Indexed: 07/09/2024]
Abstract
Warming of aquatic ecosystems is transforming the distribution, phenology and growth of the organisms dependent upon these ecosystems. Aquatic insects such as stoneflies are especially vulnerable to warming because the aquatic nymph stage of their life cycle depends on cool, well-oxygenated, flowing water habitat. We tracked thermal effects on available aerobic capacity of the aquatic nymph stage of an iconic and vulnerable stonefly species, the giant salmonfly (Pteronarcys californica), to compare habitat thermal regime measurements for two salmonfly populations from habitats separated by a gradient in summer weekly maximum temperatures. Contrary to expectations, the thermal optima range of the warmer habitat population was cooler than for the cooler habitat population. We posit that this unexpected interpopulation variation in thermal response is more strongly driven by diel and seasonal thermal variability than by the highest summer temperatures experienced within respective habitats. Additionally, we show that summer daily maximum temperatures could result in periodic limits in available aerobic capacity to support work of the warmer habitat nymphs and may be the mechanism underlying reduced abundance relative to the upstream cooler habitat population. Our findings provide insight into potential thermal and metabolic mechanisms that could regulate the success of ecological and culturally important aquatic insect species experiencing global change. We conclude that thermal regimes and thermal variation, not just mean and maximum temperatures, are critical drivers of aquatic insect responses to water temperatures.
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Affiliation(s)
| | - Michael MacDonald
- Department of Ecology, Montana State University, Bozeman, MT 59717, USA
| | - Ben Noble
- Department of Ecology, Montana State University, Bozeman, MT 59717, USA
| | - Gavin Demorest
- Department of Ecology, Montana State University, Bozeman, MT 59717, USA
| | - Alzada Roche
- Department of Ecology, Montana State University, Bozeman, MT 59717, USA
| | - Kayleigh Frazier
- Department of Ecology, Montana State University, Bozeman, MT 59717, USA
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2
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Foulk A, Gouhier T, Choi F, Torossian JL, Matzelle A, Sittenfeld D, Helmuth B. Physiologically informed organismal climatologies reveal unexpected spatiotemporal trends in temperature. CONSERVATION PHYSIOLOGY 2024; 12:coae025. [PMID: 38779431 PMCID: PMC11109819 DOI: 10.1093/conphys/coae025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/22/2023] [Revised: 03/15/2024] [Accepted: 04/15/2024] [Indexed: 05/25/2024]
Abstract
Body temperature is universally recognized as a dominant driver of biological performance. Although the critical distinction between the temperature of an organism and its surrounding habitat has long been recognized, it remains common practice to assume that trends in air temperature-collected via remote sensing or weather stations-are diagnostic of trends in animal temperature and thus of spatiotemporal patterns of physiological stress and mortality risk. Here, by analysing long-term trends recorded by biomimetic temperature sensors designed to emulate intertidal mussel temperature across the US Pacific Coast, we show that trends in maximal organismal temperature ('organismal climatologies') during aerial exposure can differ substantially from those exhibited by co-located environmental data products. Specifically, using linear regression to compare maximal organismal and environmental (air temperature) climatologies, we show that not only are the magnitudes of body and air temperature markedly different, as expected, but so are their temporal trends at both local and biogeographic scales, with some sites showing significant decadal-scale increases in organismal temperature despite reductions in air temperature, or vice versa. The idiosyncratic relationship between the spatiotemporal patterns of organismal and air temperatures suggests that environmental climatology cannot be statistically corrected to serve as an accurate proxy for organismal climatology. Finally, using quantile regression, we show that spatiotemporal trends vary across the distribution of organismal temperature, with extremes shifting in different directions and at different rates than average metrics. Overall, our results highlight the importance of quantifying changes in the entire distribution of temperature to better predict biological performance and dispel the notion that raw or 'corrected' environmental (and specially air temperature) climatologies can be used to predict organismal temperature trends. Hence, despite their widespread coverage and availability, the severe limitations of environmental climatologies suggest that their role in conservation and management policy should be carefully considered.
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Affiliation(s)
- Aubrey Foulk
- Department of Marine and Environmental Sciences, Northeastern University Marine Science Center, Nahant, MA 01908, USA
| | - Tarik Gouhier
- Department of Marine and Environmental Sciences, Northeastern University Marine Science Center, Nahant, MA 01908, USA
| | - Francis Choi
- Department of Marine and Environmental Sciences, Northeastern University Marine Science Center, Nahant, MA 01908, USA
| | - Jessica L Torossian
- Department of Marine and Environmental Sciences, Northeastern University Marine Science Center, Nahant, MA 01908, USA
- Volpe Center, U.S. Department of Transportation, Cambridge, MA 02142, USA
| | - Allison Matzelle
- Department of Marine and Environmental Sciences, Northeastern University Marine Science Center, Nahant, MA 01908, USA
| | - David Sittenfeld
- Center for the Environment, Museum of Science, Boston, MA 02114, USA
- School of Public Policy and Urban Affairs, Northeastern University, Boston, MA 02115, USA
| | - Brian Helmuth
- Department of Marine and Environmental Sciences, Northeastern University Marine Science Center, Nahant, MA 01908, USA
- School of Public Policy and Urban Affairs, Northeastern University, Boston, MA 02115, USA
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3
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Fleming JM, Marshall KE, Coverley AJ, Sheldon KS. Diurnal temperature variation impacts energetics but not reproductive effort across seasons in a temperate dung beetle. Ecology 2024; 105:e4232. [PMID: 38290131 DOI: 10.1002/ecy.4232] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Revised: 06/11/2023] [Accepted: 10/23/2023] [Indexed: 02/01/2024]
Abstract
Temperature varies on multiple timescales and ectotherms must adjust to these changes to survive. These adjustments may lead to energetic trade-offs between self-maintenance and reproductive investment. However, we know little about how diurnal and seasonal temperature changes impact energy allocation. Here we used a combination of empirical data and modeling of both thermoregulatory behaviors and body temperature to examine potential energetic trade-offs in the dung beetle Onthophagus taurus. Beginning in March 2020, universities and laboratories were officially closed due to the COVID-19 pandemic. We thus performed experiments at a private residence near Knoxville, Tennessee, USA, leveraging the heating, ventilation and air conditioning of the home to manipulate temperature and compare beetle responses to stable indoor temperatures versus variable outdoor temperatures. We collected O. taurus beetles in the early-, mid-, and late-breeding seasons to examine energetics and reproductive output in relation to diurnal and seasonal temperature fluctuations. We recorded the mass of field fresh beetles before and after a 24-h fast and used the resulting change in mass as a proxy for energetic costs of self-maintenance across seasons. To understand the impacts of diurnal fluctuations on energy allocation, we held beetles either indoors or outdoors for 14-day acclimation trials, fed them cow dung, and recorded mass change and reproductive output. Utilizing biophysical models, we integrated individual-level biophysical characteristics, microhabitat-specific performance, respirometry data, and thermoregulatory behaviors to predict temperature-induced changes to the allocation of energy toward survival and reproduction. During 24 h of outdoor fasting, we found that beetles experiencing reduced temperature variation lost more mass than those experiencing greater temperature variation, and this was not affected by season. By contrast, during the 14-day acclimation trials, we found that beetles experiencing reduced temperature variation (i.e., indoors) gained more mass than those experiencing greater temperature variation (i.e., outdoors). This effect may have been driven by shifts in the metabolism of the beetles during acclimation to increased temperature variation. Despite the negative relationship between temperature variation and energetic reserves, the only significant predictor of reproductive output was mean temperature. Taken together, we find that diurnal temperature fluctuations are important for driving energetics, but not reproductive output.
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Affiliation(s)
- J Morgan Fleming
- Department of Ecology and Evolutionary Biology, University of Tennessee, Knoxville, Tennessee, USA
| | - Katie E Marshall
- Department of Zoology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Alexander J Coverley
- Department of Zoology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Kimberly S Sheldon
- Department of Ecology and Evolutionary Biology, University of Tennessee, Knoxville, Tennessee, USA
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4
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Litmer AR, Beaupre SJ. Cycling temperature treatments affect estimates of digestive performance in prairie lizards (Sceloporus consobrinus). J Exp Biol 2024; 227:jeb247006. [PMID: 38299309 DOI: 10.1242/jeb.247006] [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: 11/08/2023] [Accepted: 01/22/2024] [Indexed: 02/02/2024]
Abstract
In nature, many organisms experience a daily range of body temperatures. Thermal performance at stable temperatures is often extrapolated to predict function in cyclical environments. However, temperature order and cyclicity may influence physiological processes. The current study compared energy intake, digestive passage time and energy budgets at a stable temperature (33°C) and two temperature cycles in lizards (Sceloporus consobrinus), to determine (1) whether stable treatments adequately project performance in a cycling environment and (2) whether temperature order influences performance. Cycles had a mean temperature of 33°C, and rotated through 30°C, 33°C and 36°C daily, with equal durations of time at each temperature but differing temperature order, with warm days and cool nights in cycle 1 and cool days and warm nights in cycle 2. For analyses, performance in the stable treatment was compared with that during cycles. If temperature is the primary factor regulating performance, then performance from the stable treatment and cycles should compare favorably. However, physiological performance varied based on temperature treatment. Energy intake and budgets were similar between the stable trial and cycle 1 but not cycle 2. However, passage time did not differ. Notably, the two cycling regimes consistently varied in performance, indicating that temperature order plays a primary role in regulating performance. Physiological data collection requires careful consideration of effects of cycling versus stable temperature treatments. Stable temperatures do not consistently represent performance in cycling regimes and consideration should be paid not only to which temperatures animals experience but also to how temperature is experienced in nature.
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Affiliation(s)
- Allison R Litmer
- University of Arkansas, Department of Biological Sciences, 650 W. Dickson Street, Fayetteville, AR 72701, USA
| | - Steven J Beaupre
- University of Arkansas, Department of Biological Sciences, 650 W. Dickson Street, Fayetteville, AR 72701, USA
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5
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Dewenter BS, Shah AA, Hughes J, Poff NL, Thompson R, Kefford BJ. The thermal breadth of temperate and tropical freshwater insects supports the climate variability hypothesis. Ecol Evol 2024; 14:e10937. [PMID: 38405410 PMCID: PMC10891360 DOI: 10.1002/ece3.10937] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2023] [Revised: 12/13/2023] [Accepted: 01/04/2024] [Indexed: 02/27/2024] Open
Abstract
Climate change involves increases in mean temperature and changes in temperature variability at multiple temporal scales but research rarely considers these temporal scales. The climate variability hypothesis (CVH) provides a conceptual framework for exploring the potential effects of annual scale thermal variability across climatic zones. The CVH predicts ectotherms in temperate regions tolerate a wider range of temperatures than those in tropical regions in response to greater annual variability in temperate regions. However, various other aspects of thermal regimes (e.g. diel variability), organisms' size and taxonomic identity are also hypothesised to influence thermal tolerance. Indeed, high temperatures in the tropics have been proposed as constraining organisms' ability to tolerate a wide range of temperatures, implying that high annual maximum temperatures would be associated with tolerating a narrow range of temperatures. We measured thermal regimes and critical thermal limits (CTmax and CTmin) of freshwater insects in the orders Ephemeroptera (mayflies), Plecoptera (stoneflies) and Trichoptera (caddisflies) along elevation gradients in streams in temperate and tropical regions of eastern Australia and tested the CVH by determining which variables were most correlated with thermal breadth (T br = CTmax - CTmin). Consistent with the CVH, T br tended to increase with increasing annual temperature range. T br also increased with body size and T br was generally wider in Plecoptera than in Ephemeroptera or Trichoptera. We also find some support for a related hypothesis, the climate extreme hypothesis (CEH), particularly for predicting upper thermal limits. We found no evidence that higher annual maximum temperature constrained individuals' abilities to tolerate a wide range of temperatures. The support for the CVH we document suggests that temperate organisms may be able to tolerate wider ranges of temperatures than tropical organisms. There is an urgent need to investigate other aspects of thermal regimes, such as diel temperature cycling and minimum temperature.
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Affiliation(s)
- Beatrice S. Dewenter
- Centre for Applied Water Science, Institute for Applied EcologyUniversity of CanberraCanberraAustralian Capital TerritoryAustralia
| | - Alisha A. Shah
- W.K. Kellogg Biological Station, Department of Integrative BiologyMichigan State UniversityEast LansingMichiganUSA
| | - Jane Hughes
- School of Environment and ScienceGriffith UniversityNathanQueenslandAustralia
| | - N. LeRoy Poff
- Centre for Applied Water Science, Institute for Applied EcologyUniversity of CanberraCanberraAustralian Capital TerritoryAustralia
- Department of BiologyColorado State UniversityFort CollinsColoradoUSA
| | - Ross Thompson
- Centre for Applied Water Science, Institute for Applied EcologyUniversity of CanberraCanberraAustralian Capital TerritoryAustralia
| | - Ben J. Kefford
- Centre for Applied Water Science, Institute for Applied EcologyUniversity of CanberraCanberraAustralian Capital TerritoryAustralia
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6
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Strait JT, Grummer JA, Hoffman NF, Muhlfeld CC, Narum SR, Luikart G. Local environments, not invasive hybridization, influence cardiac performance of native trout under acute thermal stress. Evol Appl 2024; 17:e13663. [PMID: 38390377 PMCID: PMC10883762 DOI: 10.1111/eva.13663] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2023] [Revised: 12/08/2023] [Accepted: 01/17/2024] [Indexed: 02/24/2024] Open
Abstract
Climate-induced expansion of invasive hybridization (breeding between invasive and native species) poses a significant threat to the persistence of many native species worldwide. In the northern U.S. Rocky Mountains, hybridization between native cutthroat trout and non-native rainbow trout has increased in recent decades due, in part, to climate-driven increases in water temperature. It has been postulated that invasive hybridization may enhance physiological tolerance to climate-induced thermal stress because laboratory studies indicate that rainbow trout have a higher thermal tolerance than cutthroat trout. Here, we assessed whether invasive hybridization improves cardiac performance response to acute water temperature stress of native wild trout populations. We collected trout from four streams with a wide range of non-native admixture among individuals and with different temperature and streamflow regimes in the upper Flathead River drainage, USA. We measured individual cardiac performance (maximum heart rate, "MaxHR", and temperature at arrhythmia, "ArrTemp") during laboratory trials with increasing water temperatures (10-28°C). Across the study populations, we observed substantial variation in cardiac performance of individual trout when exposed to thermal stress. Notably, we found significant differences in the cardiac response to thermal regimes among native cutthroat trout populations, suggesting the importance of genotype-by-environment interactions in shaping the physiological performance of native cutthroat trout. However, rainbow trout admixture had no significant effect on cardiac performance (MaxHR and ArrTemp) within any of the three populations. Our results indicate that invasive hybridization with a warmer-adapted species does not enhance the cardiac performance of native trout under warming conditions. Maintaining numerous populations across thermally and hydrologically diverse stream environments will be crucial for native trout to adapt and persist in a warming climate.
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Affiliation(s)
- Jeffrey T Strait
- Flathead Lake Biological Station, Wildlife Biology Program University of Montana Polson Montana USA
| | - Jared A Grummer
- Flathead Lake Biological Station, Wildlife Biology Program University of Montana Polson Montana USA
| | | | - Clint C Muhlfeld
- U.S. Geological Survey, Northern Rocky Mountain Science Center West Glacier Montana USA
| | - Shawn R Narum
- Columbia River Inter-Tribal Fish Commission Hagerman Idaho USA
| | - Gordon Luikart
- Flathead Lake Biological Station, Wildlife Biology Program University of Montana Polson Montana USA
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7
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González-Olalla JM, Powell JA, Brahney J. Dust storms increase the tolerance of phytoplankton to thermal and pH changes. GLOBAL CHANGE BIOLOGY 2024; 30:e17055. [PMID: 38273543 DOI: 10.1111/gcb.17055] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2023] [Revised: 10/31/2023] [Accepted: 11/08/2023] [Indexed: 01/27/2024]
Abstract
Aquatic communities are increasingly subjected to multiple stressors through global change, including warming, pH shifts, and elevated nutrient concentrations. These stressors often surpass species tolerance range, leading to unpredictable consequences for aquatic communities and ecosystem functioning. Phytoplankton, as the foundation of the aquatic food web, play a crucial role in controlling water quality and the transfer of nutrients and energy to higher trophic levels. Despite the significance in understanding the effect of multiple stressors, further research is required to explore the combined impact of multiple stressors on phytoplankton. In this study, we used a combination of crossed experiment and mechanistic model to analyze the ecological and biogeochemical effects of global change on aquatic ecosystems and to forecast phytoplankton dynamics. We examined the effect of dust (0-75 mg L-1 ), temperature (19-27°C), and pH (6.3-7.3) on the growth rate of the algal species Scenedesmus obliquus. Furthermore, we carried out a geospatial analysis to identify regions of the planet where aquatic systems could be most affected by atmospheric dust deposition. Our mechanistic model and our empirical data show that dust exerts a positive effect on phytoplankton growth rate, broadening its thermal and pH tolerance range. Finally, our geospatial analysis identifies several high-risk areas including the highlands of the Tibetan Plateau, western United States, South America, central and southern Africa, central Australia as well as the Mediterranean region where dust-induced changes are expected to have the greatest impacts. Overall, our study shows that increasing dust storms associated with a more arid climate and land degradation can reverse the negative effects of high temperatures and low pH on phytoplankton growth, affecting the biogeochemistry of aquatic ecosystems and their role in the cycles of the elements and tolerance to global change.
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Affiliation(s)
| | - James A Powell
- Department of Mathematics and Statistics, Utah State University, Logan, Utah, USA
| | - Janice Brahney
- Department of Watershed Sciences, Utah State University, Logan, Utah, USA
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8
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Qu HC, Yang Y, Cui ZC, Wang D, Xue CD, Qin KR. Temperature-mediated diffusion of nanoparticles in semidilute polymer solutions. Electrophoresis 2023; 44:1899-1906. [PMID: 37736676 DOI: 10.1002/elps.202300054] [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: 03/14/2023] [Revised: 09/07/2023] [Accepted: 09/10/2023] [Indexed: 09/23/2023]
Abstract
The temperature is often a critical factor affecting the diffusion of nanoparticles in complex physiological media, but its specific effects are still to be fully understood. Here, we constructed a temperature-regulated model of semidilute polymer solution and experimentally investigated the temperature-mediated diffusion of nanoparticles using the particle tracking method. By examining the ensemble-averaged mean square displacements (MSDs), we found that the MSD grows gradually as the temperature increases while the transition time from sublinear to linear stage in MSD decreases. Meanwhile, the temperature-dependent measured diffusivity of the nanoparticles shows an exponential growth. We revealed that these temperature-mediated changes are determined by the composite effect of the macroscale property of polymer solution and the microscale dynamics of polymer chain as well as nanoparticles. Furthermore, the measured non-Gaussian displacement probability distributions were found to exhibit non-Gaussian fat tails, and the tailed distribution is enhanced as the temperature increases. The non-Gaussianity was calculated and found to vary in the same trend with the tailed distribution, suggesting the occurrence of hopping events. This temperature-mediated non-Gaussian feature validates the recent theory of thermally induced activated hopping. Our results highlight the temperature-mediated changes in diffusive transport of nanoparticles in polymer solutions and may provide the possible strategy to improve drug delivery in physiological media.
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Affiliation(s)
- Heng-Chao Qu
- Affiliated Central Hospital of Dalian University of Technology, Dalian, P. R. China
- School of Optoelectronic Engineering and Instrumentation Science, Dalian University of Technology, Dalian, P. R. China
| | - Yi Yang
- School of Optoelectronic Engineering and Instrumentation Science, Dalian University of Technology, Dalian, P. R. China
| | - Zhi-Chao Cui
- School of Optoelectronic Engineering and Instrumentation Science, Dalian University of Technology, Dalian, P. R. China
| | - Dong Wang
- Affiliated Central Hospital of Dalian University of Technology, Dalian, P. R. China
| | - Chun-Dong Xue
- Affiliated Central Hospital of Dalian University of Technology, Dalian, P. R. China
- School of Optoelectronic Engineering and Instrumentation Science, Dalian University of Technology, Dalian, P. R. China
- Faculty of Medicine, Dalian University of Technology, Dalian, P. R. China
| | - Kai-Rong Qin
- Affiliated Central Hospital of Dalian University of Technology, Dalian, P. R. China
- Faculty of Medicine, Dalian University of Technology, Dalian, P. R. China
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9
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Mejia FH, Ouellet V, Briggs MA, Carlson SM, Casas-Mulet R, Chapman M, Collins MJ, Dugdale SJ, Ebersole JL, Frechette DM, Fullerton AH, Gillis CA, Johnson ZC, Kelleher C, Kurylyk BL, Lave R, Letcher BH, Myrvold KM, Nadeau TL, Neville H, Piégay H, Smith KA, Tonolla D, Torgersen CE. Closing the gap between science and management of cold-water refuges in rivers and streams. GLOBAL CHANGE BIOLOGY 2023; 29:5482-5508. [PMID: 37466251 PMCID: PMC10615108 DOI: 10.1111/gcb.16844] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Revised: 05/06/2023] [Accepted: 06/09/2023] [Indexed: 07/20/2023]
Abstract
Human activities and climate change threaten coldwater organisms in freshwater ecosystems by causing rivers and streams to warm, increasing the intensity and frequency of warm temperature events, and reducing thermal heterogeneity. Cold-water refuges are discrete patches of relatively cool water that are used by coldwater organisms for thermal relief and short-term survival. Globally, cohesive management approaches are needed that consider interlinked physical, biological, and social factors of cold-water refuges. We review current understanding of cold-water refuges, identify gaps between science and management, and evaluate policies aimed at protecting thermally sensitive species. Existing policies include designating cold-water habitats, restricting fishing during warm periods, and implementing threshold temperature standards or guidelines. However, these policies are rare and uncoordinated across spatial scales and often do not consider input from Indigenous peoples. We propose that cold-water refuges be managed as distinct operational landscape units, which provide a social and ecological context that is relevant at the watershed scale. These operational landscape units provide the foundation for an integrated framework that links science and management by (1) mapping and characterizing cold-water refuges to prioritize management and conservation actions, (2) leveraging existing and new policies, (3) improving coordination across jurisdictions, and (4) implementing adaptive management practices across scales. Our findings show that while there are many opportunities for scientific advancement, the current state of the sciences is sufficient to inform policy and management. Our proposed framework provides a path forward for managing and protecting cold-water refuges using existing and new policies to protect coldwater organisms in the face of global change.
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Affiliation(s)
- Francine H. Mejia
- U.S. Geological Survey, Forest and Rangeland Ecosystem Science Center, Cascadia Field Station, Seattle, Washington, USA
| | - Valerie Ouellet
- National Oceanic and Atmospheric Administration, Northeast Fisheries Science Center, Orono, Maine, USA
| | - Martin A. Briggs
- Observing Systems Division, U.S. Geological Survey, Hydrologic Remote Sensing Branch, Storrs, Connecticut, USA
| | - Stephanie M. Carlson
- Department of Environmental Science, Policy, and Management, University of California, Berkeley, California, USA
| | - Roser Casas-Mulet
- Aquatic Systems Biology Unit, TUM School of Life Sciences, Technical University of Munich, Freising, Germany
- Department of Infrastructure Engineering, School of Engineering, University of Melbourne, Melbourne, Victoria, Australia
| | - Mollie Chapman
- Department of Geography, URPP Global Change and Biodiversity, University of Zurich, Zurich, Switzerland
| | - Mathias J. Collins
- National Marine Fisheries Service, National Oceanic and Atmospheric Administration, Gloucester, Massachusetts, USA
| | | | - Joseph L. Ebersole
- Office of Research and Development, U.S. Environmental Protection Agency, Corvallis, Oregon, USA
| | - Danielle M. Frechette
- Maine Department of Marine Resources, Bureau of Sea Run Fisheries and Habitat, Augusta, Maine, USA
| | - Aimee H. Fullerton
- Northwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Association, Seattle, Washington, USA
| | | | - Zachary C. Johnson
- U.S. Geological Survey, Washington Water Science Center, Tacoma, Washington, USA
| | - Christa Kelleher
- Department of Civil and Environmental Engineering, Lafayette College, Easton, Pennsylvania, USA
- Department of Earth and Environmental Sciences, Syracuse University, Syracuse, New York, USA
| | - Barret L. Kurylyk
- Department of Civil and Resource Engineering, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Rebecca Lave
- Department of Geography, Indiana University, Bloomington, Indiana, USA
| | - Benjamin H. Letcher
- U.S. Geological Survey, Eastern Ecological Science Center, S.O. Conte Fish Research Center, Turners Falls, Massachusetts, USA
| | - Knut M. Myrvold
- Norwegian Institute for Nature Research, Lillehammer, Norway
| | - Tracie-Lynn Nadeau
- Region 10, Water Division, Oregon Operations Office, U.S. Environmental Protection Agency, Portland, Oregon, USA
| | | | - Herve Piégay
- UMR 5600 CNRS EVS, École Normale Supérieure de Lyon, University of Lyon, Lyon, France
| | - Kathryn A. Smith
- Department of Civil and Resource Engineering, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Diego Tonolla
- Institute of Natural Resource Sciences, Zurich University of Applied Sciences, Wädenswil, Switzerland
| | - Christian E. Torgersen
- U.S. Geological Survey, Forest and Rangeland Ecosystem Science Center, Cascadia Field Station, Seattle, Washington, USA
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10
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Harding L, Jackson AL, Payne N. Energetic costs increase with faster heating in an aquatic ectotherm. CONSERVATION PHYSIOLOGY 2023; 11:coad042. [PMID: 38026795 PMCID: PMC10660381 DOI: 10.1093/conphys/coad042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Revised: 05/08/2023] [Accepted: 05/26/2023] [Indexed: 12/01/2023]
Abstract
The thermal sensitivity of metabolism is widely studied due to its perceived importance for organismal fitness and resilience to future climate change. Almost all such studies estimate metabolism at a variety of constant temperatures, with very little work exploring how metabolism varies during temperature change. However, temperature in nature is rarely static, so our existing understanding from experiments may not reflect how temperature influences metabolism in natural systems. Using closed-chamber respirometry, we estimated the aerobic metabolic rate of an aquatic ectotherm, the Atlantic ditch shrimp Palaemonetes varians, under varying thermal conditions. We continuously measured oxygen consumption of shrimp during heating, cooling and constant temperatures, starting trials at a range of acclimation temperatures and exposing shrimp to a variety of rates of temperature change. In a broad sense, cumulative oxygen consumption estimated from static temperature exposures corresponded to estimates derived from ramping experiments. However, further analyses showed that oxygen consumption increases for both faster heating and faster cooling, with rapid heating driving higher metabolic rates than if shrimp were warmed slowly. These results suggest a systematic influence of heating rate on the thermal sensitivity of metabolism. With influential concepts such as the metabolic theory of ecology founded in data from constant temperature experiments, our results encourage further exploration of how variable temperature impacts organism energetics, and to test the generality of our findings across species. This is especially important given climate forecasts of heat waves that are characterised by both increased temperatures and faster rates of change.
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Affiliation(s)
- Lucy Harding
- Department of Zoology, Trinity College Dublin, D02PN40 Dublin, Ireland
| | - Andrew L Jackson
- Department of Zoology, Trinity College Dublin, D02PN40 Dublin, Ireland
| | - Nicholas Payne
- Department of Zoology, Trinity College Dublin, D02PN40 Dublin, Ireland
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11
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von Schmalensee L. How to generate accurate continuous thermal regimes from sparse but regular temperature measurements. Methods Ecol Evol 2023. [DOI: 10.1111/2041-210x.14092] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/18/2023]
Affiliation(s)
- Loke von Schmalensee
- Department of Zoology Stockholm University Stockholm Sweden
- Bolin Centre for Climate Research Stockholm University Stockholm Sweden
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Shokri M, Cozzoli F, Vignes F, Bertoli M, Pizzul E, Basset A. Metabolic rate and climate change across latitudes: evidence of mass-dependent responses in aquatic amphipods. J Exp Biol 2022; 225:280993. [PMID: 36337048 PMCID: PMC9720750 DOI: 10.1242/jeb.244842] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2022] [Accepted: 10/28/2022] [Indexed: 11/09/2022]
Abstract
Predictions of individual responses to climate change are often based on the assumption that temperature affects the metabolism of individuals independently of their body mass. However, empirical evidence indicates that interactive effects exist. Here, we investigated the response of individual standard metabolic rate (SMR) to annual temperature range and forecasted temperature rises of 0.6-1.2°C above the current maxima, under the conservative climate change scenario IPCC RCP2.6. As a model organism, we used the amphipod Gammarus insensibilis, collected across latitudes along the western coast of the Adriatic Sea down to the southernmost limit of the species' distributional range, with individuals varying in body mass (0.4-13.57 mg). Overall, we found that the effect of temperature on SMR is mass dependent. Within the annual temperature range, the mass-specific SMR of small/young individuals increased with temperature at a greater rate (activation energy: E=0.48 eV) than large/old individuals (E=0.29 eV), with a higher metabolic level for high-latitude than low-latitude populations. However, under the forecasted climate conditions, the mass-specific SMR of large individuals responded differently across latitudes. Unlike the higher-latitude population, whose mass-specific SMR increased in response to the forecasted climate change across all size classes, in the lower-latitude populations, this increase was not seen in large individuals. The larger/older conspecifics at lower latitudes could therefore be the first to experience the negative impacts of warming on metabolism-related processes. Although the ecological collapse of such a basic trophic level (aquatic amphipods) owing to climate change would have profound consequences for population ecology, the risk is significantly mitigated by phenotypic and genotypic adaptation.
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Affiliation(s)
- Milad Shokri
- Laboratory of Ecology, Department of Biological and Environmental Sciences and Technologies, University of Salento, S.P. Lecce-Monteroni, 73100 Lecce, Italy,Authors for correspondence (; )
| | - Francesco Cozzoli
- Laboratory of Ecology, Department of Biological and Environmental Sciences and Technologies, University of Salento, S.P. Lecce-Monteroni, 73100 Lecce, Italy,Research Institute on Terrestrial Ecosystems (IRET–URT Lecce), National Research Council of Italy (CNR), Campus Ecotekne, S.P. Lecce-Monteroni, 73100 Lecce, Italy,Authors for correspondence (; )
| | - Fabio Vignes
- Laboratory of Ecology, Department of Biological and Environmental Sciences and Technologies, University of Salento, S.P. Lecce-Monteroni, 73100 Lecce, Italy
| | - Marco Bertoli
- Department of Life Science, University of Trieste, Via Giorgieri 10, 34127 Trieste, Italy
| | - Elisabetta Pizzul
- Department of Life Science, University of Trieste, Via Giorgieri 10, 34127 Trieste, Italy
| | - Alberto Basset
- Laboratory of Ecology, Department of Biological and Environmental Sciences and Technologies, University of Salento, S.P. Lecce-Monteroni, 73100 Lecce, Italy,National Biodiversity Future Center, Palermo 90133, Italy
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