MBSS Site Summary for: CH-S-123-317-95


Located on BEAVERDAM CR 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 8/17/1995.

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 Fair - 3.7 / 5.0
Benthic IBI Good - 5.0 / 5.0

Land Use

Land use can provide important information for determining stream health.
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Catchment area 9,670 acres A stream flowing through a densely forested area. An example of a forested stream.
Urban Land Use 1.3 %
Agricultural Land Use 9.8 %
Forested Land Use 86.9 %


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

Physical Stream Habitat
Instream Habitat 13/20 (Suboptimal)
Epifaunal Substrate 11/20 (Suboptimal)
Velocity/Depth Diversity 11/20 (Suboptimal)
Pool Quality
Pool Extent = meters 		16/20 (Optimal)
Riffle Quality 6/20 (Marginal)
Shading 92 %
Embeddedness 65 %
The embeddedness, a measure of silt on the stream bottom, was 65%. This is relatively high, and may exclude some biota.


Stream Water Quality:
Water temperature 25.1 ° C
Dissolved oxygen (DO) 4.8 mg/L
Dissolved oxygen levels measured in the stream were very low (4.8 mg/L). Many fishes and other aquatic animals cannot tolerate low levels of oxygen in the water.
pH (lab) 6.07
Conductivity 84 µmho/cm
Alkalinity
(acid neutralizing capacity) 		65.3 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 14 fish species were collected.
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Common name Count
Redbreast Sunfish 59
Creek Chubsucker 13
American Eel 12
Bluegill 11
Margined Madtom 9
Tessellated Darter 8
Pumpkinseed 6
Pirate Perch 3
Brown Bullhead 2
Chain Pickerel 1
Eastern Mudminnow 1
Largemouth Bass 1
Least Brook Lamprey 1
Lepomis Hybrid 1
Biologists sampling fish communities.
Electrofishing to sample fish communities.

Amphibians and Reptiles:
American Bullfrog
Eastern Cricket 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 21
Prosimulium Black Fly 11
Gammarus Amphipod 7
Allocapnia Small Winter Stonefly 6
Oxyethira Microcaddisfly 5
Cheumatopsyche Net-Spinning Caddisfly 4
Tanytarsus Non-Biting Midges 4
Stegopterna Black Fly 4
Stenelmis Beetle 4
Oulimnius Riffle Beetle 3
Nectopsyche 2
Habrophlebia Prong-Gilled Mayfly 2
Psilotreta Mortarjoint Casemaker Caddisfly 2
Stenonema Flatheaded Mayfly 2
Pycnopsyche Great Autumn Brown Sedge Caddisfly 1
Caecidotea Isopod 1
Enallagma Narrow-Winged Damselfly 1
Dubiraphia Riffle Beetle 1
Ablabesmyia Non-Biting Midge 1
Planorbella 1
Helichus Beetle 1
Chrysops Deerfly 1
Chimarra Fingernet Caddisfly 1
Amphinemura Spring 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.