1. Algal Control By Phosphate Restriction  Mason Lake (Irvine) contains toxic algae. They will install a water treatment plant to remove phosphate.  Newport Back Bay is nearby and may also be contaminated with the toxic algae.  Eastlake (Yorba Linda) is the control lake and is not being treated.

2. Mason Lake Sampling Site

3. Toxic Algae in Mason Lake

4. Visibility: 4cm

5. High phosphate levels are from many water fowl

6. Toxin-Producing Microcystis sp.

7. Mason Lake: One Mile From Newport Back Bay Estuary

8. Newport Back Bay

9. Urban runoff into the bay Bay

10. Storm drains with Phosphate-rich water from urban run-off

11. Phosphate-rich water dumping into the Bay

12. Upper Newport Bay  Top birding site  Home to 200 species of birds  30,000 migrating birds per day  Audubon Society/F&G conducts a monthly bird count

13. Endangered Species at Newport Back Bay: California Least Tern

14. Light- Footed Clapper Rail

15. Brown Pelican

16. Peregrine Falcon

17. Belding’s Savannah Sparrow

18. Coastal California Gnatcatcher

19. East Lake (Yorba Linda) Sampling Site

20. East Lake: Yorba Linda, CA

21. Algae is creating a foamy surface scum

22. A Diatom called Navicula is causing the foam

23. Sample Analysis  Algal Assay Species ID Cell count  Chlorophyll Assay  Flow Cytometry Species populations  Phosphate Assay

24. Algal Assay

25. Eastlake: Diatoms

26. Mason Lake: Cyanobacteria

27. Flow Cytometry is used to count algal cells and separate them by species

29. Chlorophyll Assay Filter the water to capture the algae on the filter paper

30. Mason Lake Eastlake

31. Grind up filter paper with acetone to release chlorophyll

32. After Centrifuge

33. Filter algae out of water, add a reagent that turns blue when it contacts phosphate Phosphate Assay

34. Mason Lake Eastlake Filters with algae left on them

35. The deeper the blue color, the more phosphate is present.

36. A dilution series with phosphate standard