Biofouling animals in fresh water: biology, impacts, and ecosystem engineering

Biofoulers accumulate on underwater surfaces and adversely affect human activities and infrastructure. Freshwater biofoulers are much less well-known than their marine counterparts but can be economically important: we estimate the potential global cost of freshwater biofouling to be similar to US$277 million per year. They include several groups of organisms, all of which have the potential to be ecosystem engineers with strong effects on the physical and chemical properties of freshwater habitats. Nevertheless, ecological and economic research on freshwater biofoulers has been limited. We predict that freshwater biofouling will become worse in the future as a result of human activities, such as anthropogenic introductions of exotic species, eutrophication, construction of artificial habitats, and climate change. Increasing demand for energy and water may raise the costs associated with freshwater biofouling prevention and damage repair. More research and better policies and technologies are needed to prevent escalation of biofouler impacts and their related costs.