Stroubles Creek Answer
Stroubles
Creek Sample VA SOS Multimetric Score ANSWER!
If you got the following scores (in red) correct, you are ready to monitor the streams in your area!
| Macroinvertebrates |
Counts
|
| Worms |
16
|
| Flat Worms |
36
|
| Leeches |
13
|
| Crayfishes |
1
|
| Sowbugs |
5
|
| Scuds |
11
|
| Stoneflies |
0
|
| Mayflies |
32
|
| Dragonflies and Damselflies |
1
|
| Hellgrammites, Fishflies, and Alderflies |
0
|
| Common Netspinners |
29
|
| Most Caddisflies |
0
|
| Beetles |
0
|
| Midges |
25
|
| Blackflies |
15
|
| Most True Flies |
6
|
| Gilled Snails |
0
|
| Lunged Snails |
11
|
| Clams |
0
|
| TOTAL |
201
|
Calculate the total number of organisms they collected, then use the numbers from the above table to calculate these individual metrics:
| Metric Name | Number of Metric Organisms | Total Number of Organisms in the Sample | Metric Score (Percent) | ||
| Mayflies + Stoneflies + Most Caddisfly |
32
|
Divide
By
|
201
|
Multiply
By 100
|
15.9%
|
| Common Netspinners |
29
|
Divide
By
|
201
|
Multiply
By 100
|
14.4%
|
| Lunged Snails |
11
|
Divide
By
|
201
|
Multiply
By 100
|
5.5%
|
| Beetles |
0
|
Divide
By
|
201
|
Multiply
By 100
|
0
|
| % Tolerant | % Non-Insects | |||
| Taxon | Number of Organisms in Taxon | Taxon | Number of Organisms in Taxon | |
| Worms |
16
|
Worms |
16
|
|
| Flatworms |
36
|
Flatworms |
36
|
|
| Leeches |
13
|
Leeches |
13
|
|
| Sowbugs |
5
|
Crayfish |
1
|
|
| Scuds |
11
|
Sowbugs |
5
|
|
| Dragonflies and Damselflies |
1
|
Scuds |
11
|
|
| Midges |
25
|
Gilled Snails |
0
|
|
| Blackflies |
15
|
Lunged Snails |
11
|
|
| Lunged Snails |
11
|
Clams |
0
|
|
| Clams |
0
|
|
||
| Total Tolerant Organisms |
133
|
Total Non-Insect Organisms |
93
|
|
| Total Tolerant Organisms Divided by the Total Number of Organisms in the Sample |
0.6617
|
Total Non-Insect Organisms Divided by the Total Number of Organisms in the Sample |
0.4627
|
|
| Multiply by 100 to get your Metric Score |
66.2%
|
Multiply by 100 to get your Metric Score |
46.3%
|
Now
use your individual metric scores to calculate the final ecological condition
score:
Determine whether each metric should get a score of 2,1, or 0. Write your
metric value from the previous page in the 2nd column (Your Metric Value).
Put a check in the appropriate boxes for 2,1, or 0. Then calculate the
subtotals and Save Our Streams Multimetric Index score and determine whether
the site has acceptable or unacceptable ecological condition.
| Metric | Your Metric Score | 2 | 1 | 0 |
| % Mayflies, Stoneflies, and Most Caddisfly |
15.9
|
Greater than 32.2 |
Between 16.1 - 32.2
|
Less than 16.1 x |
| % Common Netspinner |
14.4
|
Less than 19.7 x |
Between 19.7 - 34.5 | Greater than 34.5 |
| % Lunged Snail |
5.5
|
Less than 0.3 |
Between 0.3 - 1.5
|
Greater than 1.5 x |
| % Beetle |
0
|
Greater than 6.4 |
Between 3.2 - 6.4
|
Less than 3.2 x |
| % Tolerant Organisms |
66.2
|
Less than 46.7 |
Between 46.7 - 61.5
|
Greater than 61.5 x |
| % Non-Insect Organisms |
46.3
|
Less than 5.4 |
Between 5.4 - 20.8
|
Greater than 20.8 x |
|
Total # of 2s: 1 |
Total # of 1s: 0 |
Total # of 0s: 5 |
||
| Subtotals: |
Multiply by 2: 2 |
Multiply by 1: 0 |
Multiply by 0: 0 |
|
Now add the 3 subtotals to get the Save Our Streams Multimetric Index Score:______2____ |
| _____ Acceptable Conditions (9 to 12) |
| ______ Conditions cannot be Determined - Gray Area (8) |
| __X___ Unacceptable Conditions (0 to 7) |
How many scores did you get right?
If you got them all right, congratulations!
If you had trouble, practice with the other streams till you get them
all right. If you continue to have problems, please contact Stacey
Brown for help.