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Abstract Bivalve molluscs have been the focus of behavioral and physiological studies for over a century, due in part to the relative ease with which their traits can be observed. The author reviews historical methods for monitoring behavior and physiology in bivalves, and how modern methods with electronic sensors can allow for a number of parameters to be measured in a variety of conditions using low-cost components and open-source tools. Open-source hardware and software tools can allow researchers to design and build custom monitoring systems to sample organismal processes and the environment, systems that can be tailored to the particular needs of a research program. The ability to leverage shared hardware and software can streamline the development process, providing greater flexibility to researchers looking to expand the number of traits they can measure, the frequency and duration of sampling, and the number of replicate devices they can afford to deploy. 

Abstract Wave‐generated flows, associated hydrodynamic forces, and disturbances created by them play critical roles in determining the structure and health of near‐shore coastal ecosystems. Oscillatory motions produced by waves increase delivery of nutrients and food to benthic organisms, and can enhance vertical mixing to facilitate delivery of larvae and spores to the seafloor. At the same time, wave disturbances can remove individuals and biomass with far‐reaching effects on critical coastal ecosystems and the biodiversity within them. Commercial instruments designed to measure wave characteristics and the effects of wave energy can be expensive to purchase and deploy, limiting their use in large quantities or in areas where they may be lost. We have developed an inexpensive open‐source pressure transducer data logger based on an Arduino microcontroller that can be used to characterize wave conditions for deployments lasting multiple months. Our design criteria centered around simplicity, longevity, low cost, and ease of use for researchers. Housed in ubiquitous polyvinylchloride (PVC) plumbing and constructed primarily with readily available materials, the Open Wave Height Logger (OWHL) can be fabricated in a college setting with basic shop tools. The OWHL performs comparably to commercial pressure‐based wave height data loggers during tests in the field, creating the opportunity to expand the use of these sensors for applications where sufficient spatial replication or risk of instrument loss would otherwise be cost prohibitive. 

Abstract It is critical to understand how human modifications of Earth’s ecosystems are influencing ecosystem functioning, including net and gross community production ( NCP and GCP , respectively) and community respiration ( CR ). These responses are often estimated by measuring oxygen production in the light ( NCP ) and consumption in the dark ( CR ), which can then be combined to estimate GCP . However, the method used to create “dark” conditions—either experimental darkening during the day or taking measurements at night—could result in different estimates of respiration and production, potentially affecting our ability to make integrative predictions. We tested this possibility by measuring oxygen concentrations under daytime ambient light conditions, in darkened tide pools during the day, and during nighttime low tides. We made measurements every 1–3 months over one year in southeastern Alaska. Daytime respiration rates were substantially higher than those measured at night, associated with higher temperature and oxygen levels during the day and leading to major differences in estimates of GCP calculated using daytime versus nighttime measurements. Our results highlight the potential importance of measuring respiration rates during both day and night to account for effects of temperature and oxygen—especially in shallow-water, constrained systems—with implications for understanding the impacts of global change on ecosystem metabolism.