MBSS Site Summary for: PRLN-626-S-2002

Site Photos

Field photo showing stream conditions at site PRLN-626-S-2002-1 (Opens in a new window) Field photo showing stream conditions at site PRLN-626-S-2002-2 (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 3/27/2002 and again in the summer on 7/1/2002.

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.
(Hint: Screen readers will announce definitions; mouse users can hover over dotted text.)
Catchment area 484 acres A stream flowing through a densely forested area. An example of a forested stream.
Urban Land Use 0.5 %
Agricultural Land Use 2.5 %
Forested Land Use 64.6 %


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

Physical Stream Habitat
Instream Habitat 16/20 (Optimal)
Epifaunal Substrate 16/20 (Optimal)
Velocity/Depth Diversity 10/20 (Marginal)
Pool Quality
Pool Extent = 29 meters 		10/20 (Marginal)
Riffle Quality
Riffle Extent = 49 meters 		14/20 (Suboptimal)
Shading 94 %
Embeddedness 20 %


Stream Water Quality:
Water temperature 21.4 ° C
Dissolved oxygen (DO) 8.8 mg/L
pH (lab) 7.16
Conductivity 190 µmho/cm
Alkalinity
(acid neutralizing capacity) 		489.4 µeq/L
Dissolved organic carbon (DOC) 1.6 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
Blacknose Dace 134
Blue Ridge Sculpin 120
Biologists sampling fish communities.
Electrofishing to sample fish communities.

Amphibians and Reptiles:
Northern Green 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
Micropsectra Non-Biting Midges 22
Diphetor Mayfly 12
Leptophlebiidae Pronggilled Mayfly 11
Paraleptophlebia Blue Quill Mayfly 10
Amphinemura Spring Stonefly 7
Prosimulium Black Fly 4
Epeorus Mayfly 4
Cinygmula Dark Red Quill Mayfly 3
Ephemerella Sulphur Mayfly 3
Stempellinella Non-Biting Midges 3
Oulimnius Riffle Beetle 2
Isoperla Stripetail Stonefly 2
Perlidae Common Stonefly 2
Neophylax Caddisfly 2
Orthocladiinae Midge 2
Diplectrona Net-Spinning Caddisfly 2
Hydropsyche Net-Spinning Caddisfly 1
Corynoneura Non-Biting Midges 1
Eukiefferiella Non-Biting Midges 1
Cheumatopsyche Net-Spinning Caddisfly 1
Stylogomphus Clubtail Dragonfly 1
Platysmittia 1
Sialis Alderfly 1
Hexatoma Crane Fly 1
Pteronarcys Giant Stonefly 1
Polycentropus Tube Maker Caddisfly 1
Isonychia Slate Drake Mayfly 1
Allocapnia Small Winter Stonefly 1
Tvetenia Non-Biting Midges 1
Parametriocnemus Non-Biting Midges 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.