MBSS Site Summary for: PG-S-035-301-97


Located on SWANSON CR in the Patuxent River lower watershed, 8-digit code: 02131101.
This stream was visited in the spring on 3/11/1997 and again in the summer on 7/22/1997.

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 Good - 4.7 / 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 12,882 acres A stream flowing through a densely forested area. An example of a forested stream.
Urban Land Use 6.1 %
Agricultural Land Use 22.8 %
Forested Land Use 69.8 %


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

Physical Stream Habitat
Instream Habitat 7/20 (Marginal)
Epifaunal Substrate 4/20 (Poor)
Velocity/Depth Diversity 13/20 (Suboptimal)
Pool Quality
Pool Extent = meters 		13/20 (Suboptimal)
Riffle Quality 13/20 (Suboptimal)
Shading 85 %
Embeddedness 100 %
The embeddedness, a measure of silt on the stream bottom, was 100%. This is very high, and may adversely affect biotic communities.


Stream Water Quality:
Water temperature 23.1 ° C
Dissolved oxygen (DO) 6.9 mg/L
pH (lab) 7.01
Conductivity 106 µmho/cm
Alkalinity
(acid neutralizing capacity) 		230.4 µeq/L
Dissolved organic carbon (DOC) 2.8 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 17 fish species were collected.
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Common name Count
Satinfin Shiner 43
Creek Chubsucker 16
American Eel 14
Sea Lamprey 13
Tadpole Madtom 12
White Sucker 11
Fallfish 10
Pumpkinseed 8
Tessellated Darter 8
Bluegill 6
Golden Shiner 6
Eastern Mudminnow 3
Redbreast Sunfish 3
Redfin Pickerel 3
Brown Bullhead 1
Largemouth Bass 1
Least Brook Lamprey 1
Biologists sampling fish communities.
Electrofishing to sample fish communities.

Amphibians and Reptiles:
American Bullfrog
Eastern Ratsnake
Northern Green Frog
Northern Spring Peeper
Stinkpot

Crayfish:
Orconectes limosus

Exotic Plants:
No exotic plants noted.
 

Benthic Macroinvertebrates:
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Genus/Family Common Name Count
Acerpenna Tiny Blue-Winged Olive Mayflies 46
Isoperla Stripetail Stonefly 10
Ephemerella Sulphur Mayfly 10
Prosimulium Black Fly 10
Prostoia Spring Stonefly 5
Crangonyx Amphipod 4
Cheumatopsyche Net-Spinning Caddisfly 3
Tipula Crane Fly 3
Pycnopsyche Great Autumn Brown Sedge Caddisfly 2
Cricotopus/Orthocladius Midge 2
Parametriocnemus Non-Biting Midges 2
Paratanytarsus Non-Biting Midges 2
Tribelos Non-Biting Midges 2
Boyeria Spotted Darner Dragonfly 1
Stenonema Flatheaded Mayfly 1
Hydropsyche Net-Spinning Caddisfly 1
Cryptochironomus Non-Biting Midges 1
Dineutus Whirlygig Beetle 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.