IN-LAKE: Cyanobacteria, Phycoyanin & More

Absent or present? Non-detectable or is a bloom imminent? Latest results? -- click here.

As part of WORCESTER CYANOBACTERIA MONITORING COLLABORATIVE (WCMC)

The Worcester Cyanobacteria Monitoring Collaborative (WCMC) is a group of volunteer community scientists that tracks cyanobacteria activity at our local lakes and ponds. Between May and October, volunteers from Manchaug Pond Foundation and Stevens Pond collect samples 1-2 times a month and examine them under the microscope for cyanobacteria. In addition, the samples are analyzed using several other indicators of bloom risk. The WCMC is developing ways to assess risk to cyanotoxin
exposure using fast and low cost methods. These results are based on methods that are not certified by the Commonwealth of MA but are presented as recommendations so we can use to make informed choices about their contact.

The WCMC does not measure cyanotoxins, instead the group uses four parameters to determine the risk of cyanotoxin exposure. These include phycocyanin concentration, particle concentration, cyanobacteria density, and the cyanobacteria observed. Each of the results are ranked and given a color to identify severity. The overall risk of exposure at each lake is determined by reviewing all four parameters together.

TERMS:

• Risk of Exposure: Overall risk of exposure to cyanotoxins in the waterbody based on a holistic interpretation of the data collected.
• Phycocyanin: Cyanobacteria-specific pigment concentration in the water. The more phycocyanin there is in the water, the more cyanobacteria are present. However, because different kinds of cyanobacteria produce different quantities of phycocyanin, the risk of toxin production is different for the same concentration of
  phycocyanin when there are different cyanobacteria present.
• Particle Concentration: Particles include living and non-living materials and can be a proxy for overall turbidity of the water. High concentrations of particles in the water can be indicative of cyanobacteria blooms, but can also be the result of other factors such as non-living debris and sediment. The phycocyanin concentrations and cyanobacteria density help to interpret if particles are due to cyanobacteria or other sources.
• Cyanobacteria Density: The ratio of cyanobacteria to other organisms in the sample. Higher densities can indicate elevated risk of exposure to cyanotoxins. Density results do not consider concentration, but in general, systems dominated by cyanobacteria are at higher risk for producing toxins.
• Cyanobacteria Observed: Genera of cyanobacteria identified in the sample. Because different cyanobacteria have different levels of phycocyanin, observed cyanobacteria help determine the threshold of phycocyanin that is considered risky.