Nutrient Cycling and Transport by Fish and Terrestrial Insect Nutrient Subsidies to Lakes
Limnology and Oceanography
American Society of Limnology and Oceanography
Mehner et al. (2005) reported that fish feeding on terrestrial insects could be important for the nutrient budgets and cycling in lakes. They studied bleak (Alburnus alburnus) that fed largely on terrestrial insects, and they suggested that this contributed 2.1% of the nutrient budget of a 12-ha lake (Großer Va¨ tersee) and that the subsequent excretion by the fish was equivalent to 11% of epilimnetic dissolved phosphorus concentrations. They concluded that nutrients delivered to lakes via terrestrial insects and recycled by fish would be most important for small lakes because of the large perimeter-to-area ratio between donor and recipient habitats. Fish may have important impacts on the community structure of lakes (e.g., Brooks and Dodson 1965), and, under some circumstances, they may influence internal nutrient cycling and transport (e.g., Vanni et al. 1997, 2006). However, three aspects of Mehner et al.’s analysis may have led them to considerably overstate the influence of fish on nutrient budgets and terrestrial subsidies to lakes, regardless of the size of the system.
Wurtsbaugh, W.A. 2007. Nutrient cycling and transport by fish and terrestrial insect nutrient subsidies to lakes. Limnol. Oceanogr. 52: 2715-2718.