BIO ASSAY
The Bio Assay group conducts experiments to measure effects of the creek on living organisms. "Indicator species", a group of animals which are extremely sensitive to changes in its environment, are used to examine the health of the Arcade Creek
Ceriodaphnia dubia
Its high sensitivity to changes in environmental conditions makes it an ideal indicator species.
Bio Assay Students
working in the Bio Assay lab.
Bio Assay Students
working in the lab
Bio Assay Students
working in the lab
Since changes in creek water quality become apparent in the survival rates of the Ceriodaphnia dubia colony, the use of this species allows for accurate measurement of biological responses around each site. By observing the effects of this creek water on C. dubia and diatoms against controls, Bio Assay effectively monitors pollutants, namely toxins, in the creek and can effectively predict population declines of other species and help prevent them.
Bio Assay collaboratively works with the Water Chemistry group by using their creek water samples to test in the laboratory. Initial tests include pH and electrical conductivity. A control group is created as a "wasser" solution (consiting of 80% Evian and 20% Arrowhead water). A recorded number of C. dubia are then placed in vials containing creek water and "wasser" water, and are given light and time to react to their new environment. For a duration of two days, the C. dubia are counted and population changes are measured.
Large population decreases indicate the presence of toxins or an abnormally large or small pH levels. Early detection of declines in the creek's health through the observation of indicator species can be used as an effective method to promptly alert other studies so the project can restore the creek's health.