MBSS Site Summary for: PAXL-294-S-2002

Site Photos

Field photo showing stream conditions at site PAXL-294-S-2002-442 (Opens in a new window) Field photo showing stream conditions at site PAXL-294-S-2002-443 (Opens in a new window)

Located on SWANSON CR in the Patuxent River lower watershed, 8-digit code: 02131101.
This stream was visited in the spring on 3/21/2002 and again in the summer on 7/9/2002.

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 Good - 4.3 / 5.0
Benthic IBI Good - 4.4 / 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 6/20 (Marginal)
Epifaunal Substrate 4/20 (Poor)
Velocity/Depth Diversity 6/20 (Marginal)
Pool Quality
Pool Extent = 31 meters 		11/20 (Suboptimal)
Riffle Quality
Riffle Extent = 0 meters 		0/20 (Poor)
Shading 91 %
Embeddedness 50 %


Stream Water Quality:
Water temperature 21.3 ° C
Dissolved oxygen (DO) 2.1 mg/L
Dissolved oxygen levels measured in the stream were very low (2.1 mg/L). Many fishes and other aquatic animals cannot tolerate low levels of oxygen in the water.
pH (lab) 6.83
Conductivity 110 µmho/cm
Alkalinity
(acid neutralizing capacity) 		207.6 µeq/L
Dissolved organic carbon (DOC) 3.8 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 11 fish species were collected.
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Common name Count
Blacknose Dace 62
Tessellated Darter 35
White Sucker 33
Rosyside Dace 26
Sea Lamprey 26
Largemouth Bass 8
Least Brook Lamprey 7
Fallfish 4
Pumpkinseed 4
Eastern Mudminnow 3
Creek Chubsucker 1
Biologists sampling fish communities.
Electrofishing to sample fish communities.

Amphibians and Reptiles:
American Bullfrog
Eastern Cricket Frog
Northern Green Frog
Northern Two-Lined Salamander
Pickerel Frog

Crayfish:
No crayfish noted.

Exotic Plants:
Japanese Honeysuckle
Japanese Stiltgrass
 

Benthic Macroinvertebrates:
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Genus/Family Common Name Count
Ephemerella Sulphur Mayfly 54
Haploperla Green Stonefly 16
Acerpenna Tiny Blue-Winged Olive Mayflies 15
Tanytarsus Non-Biting Midges 7
Cheumatopsyche Net-Spinning Caddisfly 5
Hexatoma Crane Fly 5
Oulimnius Riffle Beetle 4
Isoperla Stripetail Stonefly 3
Hemerodromia Tiny Fly 2
Perlodidae Perlodid Stonefly 2
Orthocladius Non-Biting Midges 2
Paraphaenocladius Non-Biting Midges 1
Tipula Crane Fly 1
Chrysops Deerfly 1
Heleniella European Non-Biting Midge 1
Stenonema Flatheaded Mayfly 1
Pycnopsyche Great Autumn Brown Sedge Caddisfly 1
Neophylax Caddisfly 1
Perlidae Common Stonefly 1
Boyeria Spotted Darner Dragonfly 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.