MBSS Site Summary for: PAXL-294-S-2012

Site Photos

Field photo showing stream conditions at site PAXL-294-S-2012-1 (Opens in a new window) Field photo showing stream conditions at site PAXL-294-S-2012-2 (Opens in a new window)

Located on SWANSON CREEK in the Patuxent River lower watershed, 8-digit code: 02131101.
This stream was visited in the spring on 3/8/2012 and again in the summer on 6/7/2012.

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 - 4.1 / 5.0

Land Use

Land use can provide important information for determining stream health.
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Catchment area 3,723 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 16/20 (Optimal)
Velocity/Depth Diversity 14/20 (Suboptimal)
Pool Quality
Pool Extent = 48 meters 		15/20 (Suboptimal)
Riffle Quality
Riffle Extent = 40 meters 		17/20 (Optimal)
Shading 80 %
Embeddedness 70 %
The embeddedness, a measure of silt on the stream bottom, was 70%. This is relatively high, and may exclude some biota.
Several measures of instream habitat were considered 'Optimal' at this location.


Stream Water Quality:
pH (lab) 6.93
Alkalinity
(acid neutralizing capacity) 		195.9 µeq/L
Dissolved organic carbon (DOC) 2.6672 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 8 fish species were collected.
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Common name Count
Rosyside Dace 45
Blacknose Dace 31
Fallfish 16
Eastern Mudminnow 15
Tessellated Darter 13
American Eel 4
Creek Chubsucker 2
Tadpole Madtom 1
Biologists sampling fish communities.
Electrofishing to sample fish communities.

Amphibians and Reptiles:
Cope's Gray Treefrog
Northern Green Frog

Crayfish:
Orconectes limosus

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

Benthic Macroinvertebrates:
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Genus/Family Common Name Count
Ephemerella Sulphur Mayfly 50
Prosimulium Black Fly 17
Acerpenna Tiny Blue-Winged Olive Mayflies 14
Haploperla Green Stonefly 8
Isoperla Stripetail Stonefly 7
Amphinemura Spring Stonefly 6
PERLIDAE Common Stonefly 3
Strophopteryx Early Brown Stonefly 2
Leuctra  Rolled-Winged Stonefly 2
LEPTOPHLEBIIDAE Pronggilled Mayfly 2
Cheumatopsyche Net-Spinning Caddisfly 2
Eukiefferiella Non-Biting Midges 1
Orthocladius Non-Biting Midges 1
PERLODIDAE Perlodid Stonefly 1
Oulimnius Riffle Beetle 1
Cordulegaster Spiketail Dragonfly 1
Perlesta 1
Caecidotea Isopod 1
Maccaffertium March Brown And Cahill Mayfly 1
Stenochironomus European Non-Biting Midge 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.