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Abstract Climate change is intensifying extreme weather events, including marine heatwaves, which are prolonged periods of anomalously high sea surface temperature that pose a novel threat to aquatic animals. Tropical animals may be especially vulnerable to marine heatwaves because they are adapted to a narrow temperature range. If these animals cannot acclimate to marine heatwaves, the extreme heat could impair their behavior and fitness. Here, we investigated how marine heatwave conditions affected the performance and thermal tolerance of a tropical predatory fish, arceye hawkfish (Paracirrhites arcatus), across two seasons in Moorea, French Polynesia. We found that the fish’s daily activities, including recovery from burst swimming and digestion, were more energetically costly in fish exposed to marine heatwave conditions across both seasons, while their aerobic capacity remained the same. Given their constrained energy budget, these rising costs associated with warming may impact how hawkfish prioritize activities. Additionally, hawkfish that were exposed to hotter temperatures exhibited cardiac plasticity by increasing their maximum heart rate but were still operating within a few degrees of their thermal limits. With more frequent and intense heatwaves, hawkfish, and other tropical fishes must rapidly acclimate, or they may suffer physiological consequences that alter their role in the ecosystem.
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Bringing heatwaves into the lab: A low‐cost, open‐source, and automated system to simulate realistic warming events in an experimental setting
Abstract Aquatic ecosystems face increasing threats from heatwaves driven by anthropogenic climate change, necessitating continued research to understand and manage the ecological consequences. Experimental studies are essential for understanding the impacts of heatwaves in aquatic systems; however, traditional experimental methods often fail to capture real‐world complexity. Here, we present a method for simulating aquatic heatwaves that match the dynamic nature of real‐world heatwave events in an experimental setting. Our method allows researchers to re‐create heatwaves that have happened in the past or produce entirely new heatwave scenarios based on future projections. A Raspberry Pi serves as the foundation of our autonomous, customizable temperature control system, leveraging a low‐cost and open‐source platform for adaptability and accessibility. We demonstrate system functionality for laboratory experiments by first simulating a hypothetical marine heatwave scenario with defined temperature parameters and then replicating a real‐world marine heatwave that occurred in the Santa Barbara Channel, California, in 2015. The average difference between desired and observed temperatures was 0.023°C for the basic heatwave simulation and less than 0.001°C for the real‐world heatwave simulation, with standard deviations of 0.04°C and 0.01°C, respectively. Our novel method facilitates broader access to high‐quality and affordable tools to study extreme climate events. By adopting a more realistic experimental approach, scientists can conduct more informative aquatic heatwaves studies.
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- PAR ID:
- 10561606
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Limnology and Oceanography: Methods
- Volume:
- 23
- Issue:
- 2
- ISSN:
- 1541-5856
- Format(s):
- Medium: X Size: p. 87-96
- Size(s):
- p. 87-96
- Sponsoring Org:
- National Science Foundation
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