MBSS Site Summary for: CH-S-331-301-95


Located on MILL RUN in the Nanjemoy Creek watershed, 8-digit code: 02140110.
This stream was visited in the spring on 3/2/1995 and again in the summer on 9/12/1995.

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 Good - 4.7 / 5.0
Benthic IBI Good - 4.4 / 5.0

Land Use

Land use can provide important information for determining stream health.
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Catchment area 6,295 acres A stream flowing through a densely forested area. An example of a forested stream.
Urban Land Use 3.9 %
Agricultural Land Use 13.4 %
Forested Land Use 80.9 %


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

Physical Stream Habitat
Instream Habitat 7/20 (Marginal)
Epifaunal Substrate 4/20 (Poor)
Velocity/Depth Diversity 7/20 (Marginal)
Pool Quality
Pool Extent = meters 		16/20 (Optimal)
Riffle Quality 0/20 (Poor)
Shading 50 %
Embeddedness 100 %
The embeddedness, a measure of silt on the stream bottom, was 100%. This is very high, and may adversely affect biotic communities.


Stream Water Quality:
Water temperature 16.6 ° C
Dissolved oxygen (DO) 1.2 mg/L
Dissolved oxygen levels measured in the stream were very low (1.2 mg/L). Many fishes and other aquatic animals cannot tolerate low levels of oxygen in the water.
pH (lab) 6.35
Conductivity 90 µmho/cm
Alkalinity
(acid neutralizing capacity) 		86.3 µeq/L
Dissolved organic carbon (DOC) 3 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 16 fish species were collected.
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Common name Count
Bluegill 209
Creek Chubsucker 143
Brown Bullhead 84
Pumpkinseed 44
American Eel 36
Golden Shiner 32
White Sucker 27
Black Crappie 20
Eastern Mudminnow 20
Eastern Mosquitofish 10
Chain Pickerel 5
Largemouth Bass 5
Pirate Perch 3
Eastern Silvery Minnow 1
Least Brook Lamprey 1
Yellow Perch 1
Biologists sampling fish communities.
Electrofishing to sample fish communities.

Amphibians and Reptiles:
American Bullfrog
Eastern Painted Turtle
Pickerel Frog
Southern Leopard Frog
Stinkpot

Crayfish:
No crayfish noted.

Exotic Plants:
No exotic plants noted.
 

Benthic Macroinvertebrates:
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Genus/Family Common Name Count
Siphlonurus Gray Drake Mayfly 57
Eurylophella Mayfly 33
Leptophlebia Pronggilled Mayfly 12
Zavrelimyia Non-Biting Midges 7
Acerpenna Tiny Blue-Winged Olive Mayflies 6
Crangonyx Amphipod 5
Paraleptophlebia Blue Quill Mayfly 2
Unniella Non-Biting Midge 2
Corynoneura Non-Biting Midges 1
Parametriocnemus Non-Biting Midges 1
Thienemanniella Non-Biting Midges 1
Tribelos Non-Biting Midges 1
Dubiraphia Riffle Beetle 1
Amphinemura Spring Stonefly 1
Chrysops Deerfly 1
Stenonema Flatheaded Mayfly 1
Pisidium Freshwater Pea (Pill) Clam 1
Ceratopogonidae Biting Midge 1
Ablabesmyia Non-Biting Midge 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.