Average Chl a and Secchi Disk 1991-2006

To do this activity you will need to access the Seneca Lake data sets on an MS Excell worksheet andmake a line graph. Instructions for doing this are shown below.

Instructions to make graph

  1. Visit this website about making line graphs to learn more about line graphs
  2. Open and save the dataset for Average Secchi and Chl a in Seneca Lake

B. What are two possible explanations for the rise in secchi disk depths over the past ten years?

View Graph 1 below which is a graph of the numbers of zebra mussels in Lake Ontario and the corresponding Chl a concentrations from 1990-2004.


C. What does Graph 1 tell you about the impact of zebra mussels on the primary production in Lake Ontario?

D. If you were a scientist that researched Seneca Lake ecology would you be concerned about the impact of Zebra Mussels? Why or Why not?