MBSS Site Summary for: PAXL-331-A-2007

Site Photos

Field photo showing stream conditions at site PAXL-331-A-2007-1 (Opens in a new window) Field photo showing stream conditions at site PAXL-331-A-2007-2 (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 4/9/2007 and again in the summer on 6/12/2007.

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 - 3.7 / 5.0
Benthic IBI Good - 5.0 / 5.0

Land Use

Land use can provide important information for determining stream health.
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Catchment area 5,769 acres A stream flowing through a densely forested area. An example of a forested stream.
Urban Land Use 4.2 %
Agricultural Land Use 28.5 %
Forested Land Use 65 %


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

Physical Stream Habitat
Instream Habitat 18/20 (Optimal)
Epifaunal Substrate 9/20 (Marginal)
Velocity/Depth Diversity 14/20 (Suboptimal)
Pool Quality
Pool Extent = 67 meters 		18/20 (Optimal)
Riffle Quality
Riffle Extent = 16 meters 		11/20 (Suboptimal)
Shading 92 %
Embeddedness 70 %
The embeddedness, a measure of silt on the stream bottom, was 70%. This is relatively high, and may exclude some biota.


Stream Water Quality:
Water temperature 17.8 ° C
Dissolved oxygen (DO) 8.7 mg/L
pH (lab) 7.01
Conductivity 140 µmho/cm
Alkalinity
(acid neutralizing capacity) 		190.8 µeq/L
Dissolved organic carbon (DOC) 1.9879 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 12 fish species were collected.
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Common name Count
Fallfish 29
Sea Lamprey 28
Eastern Mudminnow 14
White Sucker 14
Tessellated Darter 11
American Eel 5
Blacknose Dace 5
Tadpole Madtom 3
Largemouth Bass 1
Pumpkinseed 1
Redbreast Sunfish 1
Satinfin Shiner 1
Biologists sampling fish communities.
Electrofishing to sample fish communities.

Amphibians and Reptiles:
Northern Green Frog
Northern Two-Lined Salamander

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 18
Orthocladius Non-Biting Midges 14
Acerpenna Tiny Blue-Winged Olive Mayflies 10
Cheumatopsyche Net-Spinning Caddisfly 8
Perlidae Common Stonefly 7
Polypedilum Non-Biting Midges 7
Rheocricotopus Non-Biting Midges 6
Haploperla Green Stonefly 5
Amphinemura Spring Stonefly 4
Tanytarsus Non-Biting Midges 2
Limnephilidae Northern Casemaker Caddisfly 2
Eukiefferiella Non-Biting Midges 2
Parametriocnemus Non-Biting Midges 2
Calopteryx Damselfly 2
Pycnopsyche Great Autumn Brown Sedge Caddisfly 2
Synurella Amphipod 1
Hagenius Clubtail Dragonfly 1
Diplectrona Net-Spinning Caddisfly 1
Hydropsyche Net-Spinning Caddisfly 1
Cryptochironomus Non-Biting Midges 1
Rheosmittia Non-Biting Midges 1
Natarsia Non-Biting Midges 1
Lepidostoma Little Brown Sedge Caddisfly 1
Macronychus Riffle Beetle 1
Oulimnius Riffle Beetle 1
Ancyronyx Spider Riffle Beetle 1
Tribelos Non-Biting Midges 1
Zavrelimyia 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.