Biological
Conditions
The health of fish and macroinvertebrate (i.e., animals
without backbones that are larger than the size of a pencil
dot) communities is a strong indication of overall stream
health.
Since the mid-1990's many natural resources professionals
working in the Anacostia watershed have monitored these
communities using an Index of Biotic Integrity
or IBI approach. The IBI compares the fish and macroinvertebrate
communities of urban streams with those of healthy reference
streams, incorporating geographical, ecosystem, community,
and population, as well as distribution and abundance
variables that account for differences in waterbody size,
type, and region of occurrence. |
| The
table on the right shows adjusted IBI scores and verbal
ratings for the Anacostia River and its tributaries. While
there are still many gaps in the Anacostia macroinvertebrate
and fish community IBI databases, available data have
proven extremely valuable in the restoration effort. |
|
| Fish |
Macroinvertebrates |
| Scores
|
Verbal
Rating |
Scores
|
Verbal
Rating |
| 47
- 50 |
Excellent
|
36
- 40 |
Excellent
|
| 35
- 46 |
Good
|
27
- 35 |
Good
|
| 23
- 34 |
Fair |
17
- 26 |
Fair |
| 0
- 22 |
Poor
|
0
- 16 |
Poor
|
|
Click on the following links for graphs
showing biological conditions in the
Indian
Creek
subwatershed.
There are currently no Fish
IBI
results for the
Indian
Creek
subwatershed.
The
adjusted Macroinvertebrate
IBI
score
puts the overall health of the Indian Creek subwatershed
macroinvertebrate community in the Excellent range.
|
|
|
|
|
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