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Thomas J Kwak

Unit Leader Research Fish Biologist

Cooperative Research Units

Office Phone: 919-513-2696
Fax: 919-515-4454
ORCID: 0000-0002-0616-137X

Supervisor: James B Grand
Abstract (from Freshwater mussels (Unionidae) are a highly imperilled faunal group. One critical threat is thermal sensitivity, because global climate change and other anthropogenic activities contribute to increasing stream temperature and altered hydrologic flow that may be detrimental to freshwater mussels. We incorporated four benthic environmental components – temperature, sediment, water level (a surrogate for flow) and a vertical thermal gradient in the sediment column – in laboratory mesocosm experiments with juveniles of two species of freshwater mussels (Lampsilis abrupta and Lampsilis radiata) and tested their effects on survival, burrowing...
Abstract: Rising environmental temperatures result from changes in land use and global climate and can cause significant shifts in the composition and distribution of species within communities. In freshwater systems, the larval life stage, glochidia, of Unionida mussels develops as an obligate parasite on host fish gills or fins before transforming into the juvenile stage and dropping to the sediment to complete the life cycle. Because of the relationship between freshwater mussels and their often specific host fish species, mussels are not only limited by their own variable thermal tolerances, but also by those of their host fish. Our intent was to compile data from available literature regarding thermal sensitivities...
North American freshwater mussels are in serious decline as a result of pollution and habitat destruction from human activities. In addition, many mussel species are living in habitats that push the upper limits of their heat tolerance, which may become problematic as the climate and, as a result, water temperatures warm. As part of this project, we created a set of models to predict how freshwater mussels would respond to climate change effects. Our primary objective was to help federal and state natural resource managers forecast how mussel species will respond to climate change over the next 30 to 50 years, so that managers can develop appropriate adaptation strategies to address these changes. Additionally,...
Abstract (from Scientific Data): Inland fishes provide important ecosystem services to communities worldwide and are especially vulnerable to the impacts of climate change. Fish respond to climate change in diverse and nuanced ways, which creates challenges for practitioners of fish conservation, climate change adaptation, and management. Although climate change is known to affect fish globally, a comprehensive online, public database of how climate change has impacted inland fishes worldwide and adaptation or management practices that may address these impacts does not exist. We conducted an extensive, systematic primary literature review to identify peer-reviewed journal publications describing projected and documented...
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