MBSS Site Summary for: CH-S-331-304-95


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 7/6/1995.

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 6,238 acres A stream flowing through a densely forested area. An example of a forested stream.
Urban Land Use 4 %
Agricultural Land Use 13.1 %
Forested Land Use 81.1 %


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

Physical Stream Habitat
Instream Habitat 12/20 (Suboptimal)
Epifaunal Substrate 5/20 (Poor)
Velocity/Depth Diversity 14/20 (Suboptimal)
Pool Quality
Pool Extent = meters 		13/20 (Suboptimal)
Riffle Quality 13/20 (Suboptimal)
Shading 90 %
Embeddedness 80 %
The embeddedness, a measure of silt on the stream bottom, was 80%. This is relatively high, and may exclude some biota.


Stream Water Quality:
Water temperature 22.4 ° C
Dissolved oxygen (DO) 6.4 mg/L
pH (lab) 6.46
Conductivity 58 µmho/cm
Alkalinity
(acid neutralizing capacity) 		81.5 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 15 fish species were collected.
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Common name Count
Eastern Mudminnow 95
Tessellated Darter 70
White Sucker 51
Rosyside Dace 42
Creek Chub 35
Least Brook Lamprey 31
Creek Chubsucker 29
Redbreast Sunfish 24
Bluegill 15
Blacknose Dace 14
Pumpkinseed 10
American Eel 8
Golden Shiner 7
Sea Lamprey 5
Largemouth Bass 3
Biologists sampling fish communities.
Electrofishing to sample fish communities.

Amphibians and Reptiles:
Northern Green Frog
Southern Leopard 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
Acerpenna Tiny Blue-Winged Olive Mayflies 31
Eurylophella Mayfly 13
Optioservus Riffle Beetle 9
Ephemerella Sulphur Mayfly 7
Rheotanytarsus Non-Biting Midges 6
Psectrocladius Non-Biting Midge 6
Nemouridae Nemourid Stonefly 4
Tanytarsus Non-Biting Midges 4
Paraleptophlebia Blue Quill Mayfly 3
Conchapelopia Non-Biting Midges 2
Cricotopus Non-Biting Midges 1
Polypedilum Non-Biting Midges 1
Neophylax Caddisfly 1
Chrysops Deerfly 1
Ablabesmyia Non-Biting Midge 1
Leptophlebia Pronggilled Mayfly 1
Crangonyx Amphipod 1
Oulimnius Riffle Beetle 1
Baetidae Small Minnow Mayfly 1
Amphinemura Spring Stonefly 1
Isoperla Stripetail Stonefly 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.