Insight into the combined effects of eutrophication and climate warming on fish.

Worldwide habitat degradation has created a matrix of stressors for species to navigate but understanding interactions among stressors is one of the largest knowledge deficiencies in ecological conservation. Anthropogenic eutrophication (hereafter, eutrophication) and climate warming are two of the most pervasive global stressors. The environmental and economic burdens of eutrophication and climate warming by themselves are well documented, with frequent reports of species range shifts and mortalities, fisheries collapses and contamination of drinking water. The consequences of eutrophication are predicted to surge under forecasted climate change as heat waves lead to more intense and frequent eutrophication events. However, it is unknown how climate warming and eutrophication will interact to impact the physiological performance of fish. Stressor interactions can reveal 'ecological surprises', where exposure to one stressor may heighten or reduce resilience to another stressor. This project will explore how simultaneous exposure to eutrophication and climate warming impacts the physiology, behaviour and fitness of a valuable fish species- the European grayling (Thymallus thymallus). A mechanistic, experimental approach will be implemented to assess the efficacy of physiological compensation in coping with the negative impacts of these stressors, which unless combated, may lead to cardio-respiratory compromise, impaired swimming, altered behaviour and reduced fitness. This project will unveil crucial data required to advance our understanding of stressor interactions and may ultimately aid conservation efforts in novel and changing environments.

Keywords:CLIMATE WARMING, EUTROPHICATION, FISH PHYSIOLOGY, ECOPHYSIOLOGY

Disciplines:Vertebrate biology, Ecophysiology and ecomorphology, Conservation and biodiversity