Golden Alga Workshop Summary Report - Texas Parks & Wildlife ...

facilities was a problem in North Carolina. By being close to the Atlantic in Elizabeth
City, part of the introduction could be the result of birds. Introducing fry might be
another. We really don’t know, but there are 2, possibly 3, ways this might have been
introduced.
5. Richard L. Kiesling: Analysis of Prymnesium parvum Blooms in Lake Whitney, Texas
Were nutrient bioassays included?
Single assays were performed.
Did you have a total nutrient control in the experimentation?
No full nutrient controls were performed.
Have you considered nutrient bioassays by exclusion?
We have never done this. It should be discussed and pursued. It looks promising.
A limited number of replicates that could be run on an exclusionary basis should be
considered.
How much chlorophyll was generated in blooms?
15 -10 micrograms/liter
Typically, one approach that works in a study like this is adding three to five-fold
amounts of ambient nutrients to avoid stressing the populations. Managing phosphorus
production should reduce bloom production. This is an important takeaway message.
Were the incubations stirred or mixed in any fashion?
Achieving replication or maximum growth is the main objective here. Algae don’t
respond well to any handling or storage conditions, although they are pretty good at
adapting to nutrient pulses. Bioassays are done in large pools that are gently mixed. All
bioassays are somewhat artificial. It is believed that there are nutrient effects on the
bloom. This must be studied further. “Dinoflagellate whiners” can pose a challenge!
6. Edna Graneli: Kill your Enemies and Eat Them: The Role of Prymnesium Toxins
What are the observations from reservoirs and lakes on the phytoplankton community
during a bloom? Are the blooms initially monospecific?
Glass: When the blooms start, we have mixed communities, and the toxicity is low. As
they progress, the toxicity increases, and the community becomes monospecific.
7. Paul Kugrens: Prymnesium parvum Laboratory Studies: Structure, Reproduction,
Salinity Tolerance and Bioassay
Have you found the small, immobile cells in the Colorado research?
Cyst-like structures ¾ the size of a cell have been identified in some of the Texas
samples. They are not orange but rather greenish with very small chloroplasts.
The variability in the organism, depending on the geographic location it originates from,
is remarkable. The Wyoming strain has distinctly different shapes than Texas and
Colorado samples.
How was the Colorado fish kill attributed to Prymnesium?
The head fish pathologist contacted Texas. The Colorado organism was a similar shape
(i.e. a Chrysophyte) but not Prymnesium.
PWD RP T3200-1203
Golden Alga Workshop Notes 3