 
Anabaena, Microcystis and Cylindrospermopsin algae (Click to enlarge)
My observations told me why our lake was eutrophic, but I still had not determined whether we had any toxic algae species in our lake. I found pictures of toxic algae to compare to what I saw under the microscope. I looked at the lake water under my microscope at home and saw what I thought was Cylindrospermopsida, but since it is a cylindrical algae and there are more than one type of cylindrical algae, I wasn't positive about what I was seeing. I called Mr. Kevin McCann, who is the Orlando Lake Enhancement Coordinator, and he gave me Julie Bortle's number. She is a researcher at Florida's Environmental Protection Division, and she could help me identify and take pictures of any toxic algae we might find. I went to her lab and we identified Anabaena, Microcystis, and Cylindrospermopsin. We also found Scenedesmus, Agmenellum, and a pennate diatom.
My hypothesis was correct. There are "killer algae" in my lake. But I'm not sure if they warrant the label "killer." They can be very harmful to animals that live in the water and eat large amounts of them, especially when the algae are releasing toxins. They can also be harmful to people who drink algae-contaminated water because the algae release hepatotoxins and neurotoxins (Burns, 2002). This means that the algae can damage your liver and nervous system. The algae exist in Spring Lake because of chemical factors such as storm-water runoff and a lack of shoreline vegetation.
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My third question of what to do about the problem is a tricky one. How could I influence people and a golf course to plant native Florida plants on their lakefront property? How could I help make people aware that blowing lawn clippings into storm drains and throwing trash into the street may affect a lake a mile away?
Algae on a Florida lake
I learned a very interesting thing about Florida's aquifer that may get the public's attention. Florida used to be under the ocean and is actually made up of the remains of the hard shells of sea animals. This created limestone bedrock under the state. Limestone is made up of calcium carbonate, which is dissolved by acidic water. So, under the ground, Florida has a karst topography-which means that it is full of caves that fill up with water. This is where 90% of Florida's drinking water comes from. Only 20 of about 6,400 public water systems use surface water (Drew, 2005). In many other states they do not have underground water to drink-they drink treated surface water. More and more people are moving to Florida and building houses on top of our karst system, which is leading to sinkholes and a loss of aquifer space. The pace of development also means that more people will need water to drink, so at some point we will probably need to start drinking surface water. Currently, there is no way to eradicate toxic algae from the surface water, but filters and treatment plans are being studied (Drew). If we don't take care of the lake water we have, we may need to import drinking water from other states. Maybe an article about Florida's aquifer being in danger would get people's attention as much as the article about "killer algae" got mine.
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