MBSS Site Summary for: PAXL-294-S-2017

Site Photos

Field photo showing stream conditions at site PAXL-294-S-2017-MidpointPDownstream (Opens in a new window) Field photo showing stream conditions at site PAXL-294-S-2017-MidpointPUpstream (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 3/8/2017 and again in the summer on 6/12/2017.

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 - 5.0 / 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 3,723 acres A stream flowing through a densely forested area. An example of a forested stream.
Urban Land Use 9.7 %
Agricultural Land Use 19.1 %
Forested Land Use 68 %


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

Physical Stream Habitat
Instream Habitat 15/20 (Suboptimal)
Epifaunal Substrate 14/20 (Suboptimal)
Velocity/Depth Diversity 13/20 (Suboptimal)
Pool Quality
Pool Extent = 52 meters 		15/20 (Suboptimal)
Riffle Quality
Riffle Extent = 32 meters 		9/20 (Marginal)
Shading 70 %
Embeddedness 80 %
The embeddedness, a measure of silt on the stream bottom, was 80%. This is relatively high, and may exclude some biota.


Stream Water Quality:
pH (lab) 7.3
Alkalinity
(acid neutralizing capacity) 		261.7 µeq/L
Dissolved organic carbon (DOC) 2.9937 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 13 fish species were collected.
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Common name Count
Blacknose Dace 63
Rosyside Dace 44
Sea Lamprey 21
Fallfish 15
Creek Chubsucker 14
Tessellated Darter 13
Least Brook Lamprey 12
Redbreast Sunfish 7
Eastern Mudminnow 4
American Eel 2
White Sucker 2
Green Sunfish 1
Pumpkinseed 1
Biologists sampling fish communities.
Electrofishing to sample fish communities.

Amphibians and Reptiles:
Cope's Gray Treefrog
Eastern Cricket Frog
Pickerel Frog
Southern Leopard Frog

Crayfish:
Orconectes limosus

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

Benthic Macroinvertebrates:
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Genus/Family Common Name Count
EPHEMERELLA Sulphur Mayfly 29
ACERPENNA Tiny Blue-Winged Olive Mayflies 16
ORTHOCLADIUS Non-Biting Midges 10
CHLOROPERLIDAE Green Stonefly 9
ISOPERLA Stripetail Stonefly 8
AMPHINEMURA Spring Stonefly 6
PARAMETRIOCNEMUS Non-Biting Midges 6
RHEOCRICOTOPUS Non-Biting Midges 6
HAPLOPERLA Green Stonefly 5
PROSTOIA Spring Stonefly 5
HEXATOMA Crane Fly 4
PROSIMULIUM Black Fly 3
SIMULIUM Black Fly 3
STROPHOPTERYX Early Brown Stonefly 2
STEMPELLINELLA Non-Biting Midges 2
TANYTARSUS Non-Biting Midges 2
POLYPEDILUM Non-Biting Midges 2
PERLODIDAE Perlodid Stonefly 2
HEMERODROMIA Tiny Fly 2
ISOTOMIDAE Springtail 1
OULIMNIUS Riffle Beetle 1
BOYERIA Spotted Darner Dragonfly 1
THIENEMANNIMYIA GROUP Non-Biting Midges 1
TVETENIA Non-Biting Midges 1
MACCAFFERTIUM March Brown And Cahill Mayfly 1
LYPE Net Tube Caddisfly 1
CLADOTANYTARSUS Non-Biting Midge 1
CORYNONEURA Non-Biting Midges 1
MICROTENDIPES 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.