Click on the Lake Finder Icon (Left Center of Screen)

Name ______

WWW Lake Comparison Activity

Directions:

-  Go to www.dnr.state.mn.us

-  Click on the “Lake Finder” icon (left center of screen)

-  Enter the lake name and county. Then click “Get Lake Data”.

-  Now click on “go” under the “Lake Info” column and answer the following questions.

1.  What is the lake area?

2.  What is the water clarity?

3.  Based on the data table “Length of Selected Species Sampled for All Gear for the 2002 Survey Year”, answer the following questions.

a.  What are the 2 species of fish that were most abundant in the sample?

b.  What are the 2 species of fish that were the least abundant in the sample?

c.  Why are the smaller fish species more abundant than the larger fish species (think of the energy pyramid)?

d.  Are there any specific coldwater fish species present in the sample?

Directions:

-  Click “back”.

-  Now click on “go” under the column for “Lake Water Quality” and answer the following questions.

4.  What is the “Total Phosphorus Mean” for the lake?

5.  What is the “Chlorophyll-a Mean” for the lake?

6.  What is the “Secchi Disk Mean” for the lake?

7.  Now look at the Carlson Trophic State Index graph. What is the Carlson TSI for the lake?

8.  What type of lake is it classified as?

9.  Based on what you see here, what is the current health of the lake? Explain your answer citing specific data from this webpage.

Some Sample Discussion questions that could be used.

Assume a very high load of phosphorus entered the lake. Based on your knowledge answer the following question.

a.  What would happen to the Chlorophyll-a measurement in the lake? Explain.

b.  What would happen to the turbidity of the lake? Explain.

c.  What would happen to the Carlson TSI reading? Explain.

d.  What would happen to the amount of dissolved oxygen in the lake and what effect would that have on the fish of the lake?

e.  How would you now rate the overall health of the lake?

Base on the 3 lakes that you researched, answer the following questions.

a.  What lake would you rather swim in? Explain.

b.  What lake would you rather fish in? Explain.

c.  Which lake would you rather eat fish out of? Explain.

d.  Rank your lakes in order from clearest water to most turbid.

e.  Which of the lakes in most healthy in your opinion and why?