Examining the relationship between species richness of fish communities and their biomass in freshwater ecosystems
Lennox, Preston A.
University of Lethbridge. Faculty of Arts and Science
Lethbridge, Alta. : University of lethbridge, Dept. of Biological Sciences
Models used to predict fish biomass in freshwater ecosystems are integral to fisheries management, however, are to date limited to predictions from either chemical (total phosphorus, nitrogen) or physical (morphometric) variables, and do not consider the implications of species and their influence on trophic energy transfer. Here, using empirical data, we first demonstrate that a significant relationship exists between species richness and fish biomass, which behaves similar to models proposed in terrestrial ecosystems. Second, we demonstrate the utility of modern food web analyses to quantify functional richness in freshwater fisheries, and relate functional richness to the species richness-biomass relationship. Finally, we apply this relationship to current models predicting biomass from chemical and physical drivers, and using data compiled from over 500 sites across North America, acquired from both the literature and this project, successfully demonstrate its ability to describe much of the regional variance in existing fish biomass models.
Fish , Fisheries management , Freshwater ecosystems