MBSS Site Summary for: PRLN-626-S-2001


Located on MILL RUN in the Potomac River L N Branch watershed, 8-digit code: 02141001.
This stream was visited in the spring on 4/6/2001 and again in the summer on 7/18/2001.

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 - 3.5 / 5.0
Benthic IBI Good - 4.3 / 5.0

Land Use

Land use can provide important information for determining stream health.
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Catchment area 484 acres A stream flowing through a densely forested area. An example of a forested stream.
Urban Land Use 1 %
Agricultural Land Use 3 %
Forested Land Use 64 %


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

Physical Stream Habitat
Instream Habitat 18/20 (Optimal)
Epifaunal Substrate 18/20 (Optimal)
Velocity/Depth Diversity 10/20 (Marginal)
Pool Quality
Pool Extent = 25 meters 		15/20 (Suboptimal)
Riffle Quality
Riffle Extent = 55 meters 		16/20 (Optimal)
Shading 85 %
Embeddedness 15 %
Several measures of instream habitat were considered 'Optimal' at this location.


Stream Water Quality:
Water temperature 17.6 ° C
Dissolved oxygen (DO) 8.9 mg/L
pH (lab) 7.67
Conductivity 160 µmho/cm
Alkalinity
(acid neutralizing capacity) 		544 µeq/L
Dissolved organic carbon (DOC) 0.9 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 2 fish species were collected.
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Common name Count
Blue Ridge Sculpin 137
Blacknose Dace 124
Biologists sampling fish communities.
Electrofishing to sample fish communities.

Amphibians and Reptiles:
Northern Dusky Salamander
Northern Two-Lined Salamander

Crayfish:
No crayfish noted.

Exotic Plants:
No exotic plants noted.
 

Benthic Macroinvertebrates:
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Genus/Family Common Name Count
Prosimulium Black Fly 37
Epeorus Mayfly 11
Paraleptophlebia Blue Quill Mayfly 10
Micropsectra Non-Biting Midges 8
Baetidae Small Minnow Mayfly 7
Amphinemura Spring Stonefly 7
Ephemerella Sulphur Mayfly 5
Diplectrona Net-Spinning Caddisfly 4
Leuctra  Rolled-Winged Stonefly 4
Chelifera Aquatic Dance Fly 4
Acroneuria Golden Stoneflies 3
Tvetenia Non-Biting Midges 3
Perlodidae Perlodid Stonefly 2
Neophylax Caddisfly 2
Heptageniidae Flathead Mayfly 2
Rhyacophila Free-Living Caddisfly 2
Isoperla Stripetail Stonefly 2
Pteronarcys Giant Stonefly 1
Diamesa Bloodworm 1
Tallaperla Roach-Like Stonefly 1
Thienemannimyia group Non-Biting Midges 1
Chloroperlidae Green 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.