State Water Resources Research Institute Program
Project ID: 2011WA326B
Title: Understanding Toxin Production by Harmful Algae: Vancouver Lake as a Model System
Project Type: Research
Start Date: 3/01/2011
End Date: 2/28/2012
Congressional District: Washington, 3
Focus Categories: Toxic Substances, Ecology, Water Quality
Keywords: cyanobacteria, toxin production, zooplankton grazing
Principal Investigators: Rollwagen-Bollens, Gretchen (Washington State University Vancouver); Bollens, Stephen M. (Washington State Univesity)
Federal Funds: $ 30,000
Non-Federal Matching Funds: $ 62,297
Abstract: Seasonal blooms of cyanobacteria and other algae are natural occurrences in lakes, and may naturally increase in frequency as lakes evolve from oligotrophic states (deep, clean and unproductive) to eutrophic states (shallow and infested with aquatic plants and phytoplankton). However, increasing evidence demonstrates that the eutrophication process in lakes is being accelerated by human activity, and is contributing to an increase in frequency and intensity of cyanobacteria blooms.
Excessive abundance of cyanobacteria may have detrimental effects on lake ecosystems and water quality, including development of surface scums, depleted oxygen levels, and (in some cases) production of toxins that can negatively affect aquatic life and humans. This phenomenon is of great concern to water resource managers, particularly with respect to human health, as well as to the public whose use and enjoyment of these environments may be prohibited as a result.
Vancouver Lake, in Clark County, WA, is a large, shallow lake in the lower Columbia River floodplain that is popular with the local community for swimming, boating, fishing and other recreational activities. Vancouver Lake has experienced numerous summertime blooms of Anabaena and Aphanizomenon cyanobacteria over the past 20 years, often necessitating closure of the Lake to swimming and other recreational use.
In this proposal our goal is to better understand the dynamics of toxin production by cyanobacteria in Vancouver Lake, in particular the influence of biological (e.g. grazing pressure by planktonic consumers) and environmental (e.g. temperature, nutrient levels, and turbidity) factors on both the diversity of cyanobacteria and the stimulation of toxin production by particular cyanobacteria taxa.
We have three specific objectives designed to meet our goal for this project:
The results of these analyses will allow us to more accurately define cyanobacteria diversity in Vancouver Lake and to better predict the conditions that may lead to toxic cyanobacteria blooms. This information will be critical for assisting Clark County Public Health in determining whether restrictions must be imposed on Lake usage during bloom periods. In addition, these results will complement the suite of biological and chemical data currently available to Clark County Public Works and Environmental Services to inform management decisions that may mitigate or prevent cyanobacteria blooms in the future. Finally, what we learn about Vancouver Lake will have broad implications for other lakes in Washington as well as shallow, temperate lakes around the globe.
Progress/Completion Report, 2011, PDF