MBSS Site Summary for: CH-S-213-120-95


Located on NANJEMOY CR UT1 in the Nanjemoy Creek watershed, 8-digit code: 02140110.
This stream was visited in the spring on 3/13/1995 and again in the summer on 6/1/1995.

Index of Biotic Integrity (IBI) Results:

An Index of Biotic Integrity (IBI) is a scientific tool used to identify and classify stream health. An IBI associates anthropogenic influences on a stream or with biological condition in the stream, and is formulated using data developed from biosurveys.
Details on the development and application of MBSS IBIs are in this document.
Fish IBI Poor - 1.7 / 5.0
Benthic IBI Poor - 1.9 / 5.0

Land Use

Land use can provide important information for determining stream health.
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Catchment area 494 acres A stream flowing through a densely forested area. An example of a forested stream.
Urban Land Use 1.3 %
Agricultural Land Use 19.6 %
Forested Land Use 78.9 %


Stream showing woody debris, logs, and rocky substrate.
An example of woody debris in a stream.

Physical Stream Habitat
Instream Habitat 4/20 (Poor)
Epifaunal Substrate 1/20 (Poor)
Velocity/Depth Diversity 1/20 (Poor)
Pool Quality
Pool Extent = meters 		3/20 (Poor)
Riffle Quality 0/20 (Poor)
Shading 92 %
Embeddedness 100 %
The embeddedness, a measure of silt on the stream bottom, was 100%. This is very high, and may adversely affect biotic communities.
Several measures of instream habitat were considered 'Poor' at this location.


Stream Water Quality:
Water temperature 15.8 ° C
Dissolved oxygen (DO) 0.3 mg/L
Dissolved oxygen levels measured in the stream were very low (0.3 mg/L). Many fishes and other aquatic animals cannot tolerate low levels of oxygen in the water.
pH (lab) 4.95
Conductivity 108 µmho/cm
Alkalinity
(acid neutralizing capacity) 		-11.4 µeq/L
Dissolved organic carbon (DOC) 4 mg/L

Biological Stream Condition:

Surveys of the organisms living within a stream can give indications of stream health. Species richness, or the number of different species present, as well as indicator species (species whose presence, absence or abundance can serve as a measure of environmental conditions) are informative for stream health. 		Close-up of a mayfly indicator species.

Fish Survey Results:
The following 1 fish species were collected.
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Common name Count
Eastern Mudminnow 269
Biologists sampling fish communities.
Electrofishing to sample fish communities.

Amphibians and Reptiles:
Eastern Box Turtle
Eastern Cricket Frog
Northern Green Frog
Northern Red Salamander
Pickerel Frog

Crayfish:
No crayfish noted.

Exotic Plants:
No exotic plants noted.
 

Benthic Macroinvertebrates:
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Genus/Family Common Name Count
Stegopterna Black Fly 34
Caecidotea Isopod 23
Crangonyx Amphipod 20
Thienemannimyia Non-Biting Midges 9
Pycnopsyche Great Autumn Brown Sedge Caddisfly 5
Isotomurus Elongate-Bodied Springtail 3
Heterotrissocladius European Non-Biting Midge 1
Chironomus Non-Biting Midges 1
Kick net sampling for macroinvertebrates.
Sampling with a kick net.

Information disclaimer: The information and data on this page is for guidance and general planning purposes only. It should not be used to make decisions on specific matters.