MBSS Site Summary for: PAXL-294-S-2005


Located on Swanson Creek in the Patuxent River lower watershed, 8-digit code: 02131101.
This stream was visited in the spring on 4/11/2005 and again in the summer on 7/21/2005.

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 - 3.3 / 5.0
Benthic IBI Good - 4.7 / 5.0

Land Use

Land use can provide important information for determining stream health.
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Catchment area 3,717 acres A stream flowing through a densely forested area. An example of a forested stream.
Urban Land Use 3.6 %
Agricultural Land Use 30.9 %
Forested Land Use 62.6 %


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 13/20 (Suboptimal)
Velocity/Depth Diversity 13/20 (Suboptimal)
Pool Quality
Pool Extent = 58 meters 		16/20 (Optimal)
Riffle Quality
Riffle Extent = 33 meters 		13/20 (Suboptimal)
Shading 90 %
Embeddedness 35 %


Stream Water Quality:
Water temperature 21.2 ° C
Dissolved oxygen (DO) 7.1 mg/L
pH (lab) 6.75
Conductivity 114 µmho/cm
Alkalinity
(acid neutralizing capacity) 		128.8543 µeq/L
Dissolved organic carbon (DOC) 3.016 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 10 fish species were collected.
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Common name Count
Blacknose Dace 26
Tessellated Darter 11
Eastern Mudminnow 10
Least Brook Lamprey 9
American Eel 6
Tadpole Madtom 3
Pumpkinseed 2
Redfin Pickerel 2
Golden Shiner 1
Rosyside Dace 1
Biologists sampling fish communities.
Electrofishing to sample fish communities.

Amphibians and Reptiles:
Northern Two-Lined Salamander

Crayfish:
No crayfish noted.

Exotic Plants:
Japanese Stiltgrass
Mile-A-Minute
Multiflora Rose
 

Benthic Macroinvertebrates:
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Genus/Family Common Name Count
Acerpenna Tiny Blue-Winged Olive Mayflies 41
Oulimnius Riffle Beetle 20
Ephemerella Sulphur Mayfly 14
Chloroperlidae Green Stonefly 11
Haploperla Green Stonefly 5
Gammarus Amphipod 5
Neophylax Caddisfly 3
Amphinemura Spring Stonefly 3
Anchytarsus Beetle 2
Hexatoma Crane Fly 2
Heleniella European Non-Biting Midge 1
Stenelmis Beetle 1
Hydropsychidae Common Netspinner Caddisfly 1
Perlidae Common Stonefly 1
Antocha Crane Fly 1
Eurylophella Mayfly 1
Orthocladiinae Midge 1
Hydropsyche Net-Spinning Caddisfly 1
Pseudorthocladius Non-Biting Midges 1
Rheosmittia Non-Biting Midges 1
Thienemannimyia group Non-Biting Midges 1
Leptophlebiidae Pronggilled Mayfly 1
Limnephilus 1
Boyeria Spotted Darner Dragonfly 1
Lumbriculidae Worm 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.