Eric T. Koepfler
The raphidophyte Chattonella subsalsa has been reported to cause harmful algal blooms in every major ocean. In South Carolina, C. subsalsa blooms have been observed in brackish stormwater detention ponds as well as estuarine waters neighboring urbanized areas. Blooms frequently cause fish kills although the fish kill mechanism of C. subsalsa is currently unknown. In many harmful species, the lethality of algal cells is thought to correspond with algal growth phase. Algal growth is known to progress through five distinct phases; lag, early exponential, late exponential, stationary, and decline. In nature, harmful algal blooms commonly occur in the late exponential or stationary growth phases; however, in vitro studies of Chattonella have identified the early exponential phase as most lethal. The strain of C. subsalsa used for this study was found to progress through the five growth phases in a period of twenty days. To examine the lethality of C. subsalsa at various growth phases, the zooplankton species Artemia salina was exposed to C. subsalsa culture at two-day intervals for twenty days. Deaths fluctuated among the growth phases of C. subsalsa with the highest mortalities observed in the late exponential and stationary growth phases. The late exponential and stationary growth phases were found to have significantly greater percent mortalities than the early exponential, lag phase, and control groups (Kruskal-Wallis rank sum test, p=0.05).
"Exposing Artemia Salina to Chattonella Subsalsa: A General Toxicity Test,"
Bridges: A Journal of Student Research: Vol. 10
, Article 4.
Available at: https://digitalcommons.coastal.edu/bridges/vol10/iss10/4