| dc.description.abstract | Canadian freshwater commercial and recreational fisheries contribute $8.8 billion
in revenue to the economy annually and are a significant subsistence food source for
Indigenous communities. Fish production is recognized as the best indicator of fish
population fitness and for assessing productive capacity at both the population and
community levels and is legislatively required by the Canadian federal government to
prevent, mitigate and/or monitor impacts of development in the Fisheries Act. However,
empirical tests of correlates and drivers of fish productivity are lacking due to the
extensive effort and monetary expense required to calculate estimates of production.
Using approximately 20-years of data from disturbed and undisturbed freshwater fish
populations and the environments that support them at the IISD-Experimental Lakes Area
(ELA) this dissertation explored spatiotemporal correlates and drivers of freshwater fish
production. Here, I (i) proposed modifications to current estimation methodologies
through the use of von Bertalanffy growth models to allow for estimates of negative
production, (ii) identified key fine-scale mechanisms of both population- and communitylevel fish production temporally, as well as population-level production over regional
scales, and (iii) based on these analyses, provide recommendations for variables that can
be used as surrogates of fish production. I show that physiochemical and limnological
factors that influence habitat availability (i.e., total phosphorus, dissolved organic carbon)
dictate lower food web dynamics (i.e., prey quantity and access to prey) and resulting life
history strategies (i.e., mean weight, mean length, abundance, and body condition), to
ultimately shape fish productivity, demonstrating that fish production is primarily driven
by factors that shape individual- and population-level bioenergetics. | en_US |
