MBSS Site Summary for: PRLN-626-S-2017

Site Photos

Field photo showing stream conditions at site PRLN-626-S-2017-DownstreamFromBoulderAt30m (Opens in a new window) Field photo showing stream conditions at site PRLN-626-S-2017-UpstreamFromBoulderAt30m (Opens in a new window)

Located on Mill Run in the Potomac River L N Branch watershed, 8-digit code: 02141001.
This stream was visited in the spring on 3/2/2017 and again in the summer on 6/7/2017.

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 - 4.5 / 5.0

Land Use

Land use can provide important information for determining stream health.
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Catchment area 470 acres A highly channelized urban stream with concrete banks. An example of a highly channelized urban stream.
Urban Land Use 0 %
Agricultural Land Use 0 %
Forested Land Use 100 %


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

Physical Stream Habitat
Instream Habitat 15/20 (Suboptimal)
Epifaunal Substrate 18/20 (Optimal)
Velocity/Depth Diversity 10/20 (Marginal)
Pool Quality
Pool Extent = 39 meters 		10/20 (Marginal)
Riffle Quality
Riffle Extent = 52 meters 		15/20 (Suboptimal)
Shading 75 %
Embeddedness 5 %


Stream Water Quality:
pH (lab) 7.55
Alkalinity
(acid neutralizing capacity) 		349.2 µeq/L
Dissolved organic carbon (DOC) 1.8281 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 3 fish species were collected.
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Common name Count
Blacknose Dace 38
Blue Ridge Sculpin 12
Brook Trout 5
Biologists sampling fish communities.
Electrofishing to sample fish communities.

Amphibians and Reptiles:
Northern Dusky Salamander
Northern Spring Salamander
Seal Salamander

Crayfish:
Cambarus bartonii bartonii

Exotic Plants:
Garlic Mustard
Japanese Barberry
Japanese Stiltgrass
Mile-A-Minute
Multiflora Rose
 

Benthic Macroinvertebrates:
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Genus/Family Common Name Count
AMPHINEMURA Spring Stonefly 28
EPEORUS Mayfly 21
DIPLECTRONA Net-Spinning Caddisfly 10
PROSIMULIUM Black Fly 9
EPHEMERELLA Sulphur Mayfly 7
LEUCTRA  Rolled-Winged Stonefly 5
DIPHETOR Mayfly 4
ISOPERLA Stripetail Stonefly 4
LEPTOPHLEBIIDAE Pronggilled Mayfly 3
TAENIOPTERYX Winter Stonefly 2
ACRONEURIA Golden Stoneflies 2
CHLOROPERLIDAE Green Stonefly 1
DICRANOTA Hairy-Eyed Cranefly 1
LEPIDOSTOMA Little Brown Sedge Caddisfly 1
BAETIS Blue-Winged Olive Mayfly 1
DRUNELLA Blue-Winged Olive Mayfly 1
NEOPHYLAX Caddisfly 1
AMELETUS Combmouthed Minnow Mayfly 1
WORMALDIA Fingernet Caddisfly 1
RHYACOPHILA Free-Living Caddisfly 1
NIGRONIA Megaloptera (Dark Fishfly) 1
HYDROPSYCHE Net-Spinning Caddisfly 1
MICROPSECTRA Non-Biting Midges 1
PARAMETRIOCNEMUS Non-Biting Midges 1
TVETENIA Non-Biting Midges 1
PELTOPERLIDAE Roachlike Stonefly 1
TALLAPERLA Roach-Like 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.