Here is a spring fed pond where blue-green algae is showing up. There are many different types of pond scums and blue-green algaes. Based upon samples microscope samples, this genera of blue-green algae that are capable of producing toxins. This can be harful to livestock and wildlife and is something we need to be careful about if you see this in the pond.
There must be a source of phosphorus and nitrogen that is allowing the growth of this algae. UGA Extension Aquaculture Specialist Dr. Gary Burtle says this is probably from water runoff in the winter and early spring brought nutrients into the pond. Without a volume of rainfall adequate to flush the pond, the algae continues to accumulate until scums form. Watershed ponds are more likely to flush, due to rainfall, than levee ponds used for aquaculture. We have long seen algal scum development as we feed catfish in ponds where water outflow is minimized and pumped water is used only to maintain water level. Some treatments Dr. Burtle has suggested can reduce the blue-green algae and destroy the scum.
I have information on pond scums I can send to anyone who would like to read about it. E-mail me at firstname.lastname@example.org. UGA also has a website called CyanoTracker dedicated to tracking toxic algal blooms anyone can report. If anyone wants to test water, The Warnell School of Forestry and Natural Resources and Dr. Burtle have also teamed developing a new test protocol that includes toxic algal identification.