MBSS Site Summary for: PAXL-294-S-2013

Site Photos

Field photo showing stream conditions at site PAXL-294-S-2013-MidpointPdownstream (Opens in a new window) Field photo showing stream conditions at site PAXL-294-S-2013-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 3/20/2013 and again in the summer on 6/5/2013.

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 - 4.4 / 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 13/20 (Suboptimal)
Epifaunal Substrate 12/20 (Suboptimal)
Velocity/Depth Diversity 15/20 (Suboptimal)
Pool Quality
Pool Extent = 48 meters 		17/20 (Optimal)
Riffle Quality
Riffle Extent = 42 meters 		12/20 (Suboptimal)
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) 6.85
Alkalinity
(acid neutralizing capacity) 		188.7 µeq/L
Dissolved organic carbon (DOC) 1.8977 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
Rosyside Dace 90
Tessellated Darter 86
Blacknose Dace 47
Fallfish 26
Eastern Mudminnow 16
American Eel 9
Creek Chubsucker 7
Sea Lamprey 6
Least Brook Lamprey 2
Tadpole Madtom 2
White Sucker 1
Biologists sampling fish communities.
Electrofishing to sample fish communities.

Amphibians and Reptiles:
American Bullfrog
Eastern Box Turtle
Fowler's Toad
Northern Spring Peeper
Pickerel Frog

Crayfish:
Cambarus bartonii bartonii
Cambarus diogenes
Orconectes limosus

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

Benthic Macroinvertebrates:
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Genus/Family Common Name Count
Ephemerella Sulphur Mayfly 38
Prosimulium Black Fly 19
Acerpenna Tiny Blue-Winged Olive Mayflies 13
Haploperla Green Stonefly 9
Amphinemura Spring Stonefly 5
Cheumatopsyche Net-Spinning Caddisfly 4
Neophylax Caddisfly 2
Hexatoma Crane Fly 2
Prostoia Spring Stonefly 2
Isoperla Stripetail Stonefly 2
Orthocladius Non-Biting Midges 2
Oulimnius Riffle Beetle 2
TUBIFICIDAE Aquatic Worm 1
Polypedilum Non-Biting Midges 1
LIMNEPHILIDAE Northern Casemaker Caddisfly 1
LUMBRICULIDAE Worm 1
Tipula Crane Fly 1
Strophopteryx Early Brown Stonefly 1
Eukiefferiella Non-Biting Midges 1
Micropsectra Non-Biting Midges 1
Xylotopus 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.