MBSS Site Summary for: PAXL-106-R-2004

Site Photos

Field photo showing stream conditions at site PAXL-106-R-2004-1 (Opens in a new window) Field photo showing stream conditions at site PAXL-106-R-2004-2 (Opens in a new window)

Located on SEWELL BR UT in the Patuxent River lower watershed, 8-digit code: 02131101.
This stream was visited in the spring on 3/2/2004 and again in the summer on 7/13/2004.

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 Poor - 1.7 / 5.0
Benthic IBI Poor - 2.7 / 5.0

Land Use

Land use can provide important information for determining stream health.
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Catchment area 723 acres A stream flowing through a densely forested area. An example of a forested stream.
Urban Land Use 12 %
Agricultural Land Use 26 %
Forested Land Use 58 %


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 7/20 (Marginal)
Velocity/Depth Diversity 7/20 (Marginal)
Pool Quality
Pool Extent = 60 meters 		6/20 (Marginal)
Riffle Quality
Riffle Extent = 15 meters 		11/20 (Suboptimal)
Shading 90 %
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 22.5 ° C
Dissolved oxygen (DO) 7.6 mg/L
pH (lab) 7.1
Conductivity 221 µmho/cm
Alkalinity
(acid neutralizing capacity) 		513.3 µeq/L
Dissolved organic carbon (DOC) 1.8 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 3 fish species were collected.
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Common name Count
Eastern Mudminnow 40
Blacknose Dace 1
Tessellated Darter 1
Biologists sampling fish communities.
Electrofishing to sample fish communities.

Amphibians and Reptiles:
Eastern Box Turtle
Northern Green Frog
Northern Spring Peeper
Pickerel Frog
Wood Frog

Crayfish:
No crayfish noted.

Exotic Plants:
Japanese Stiltgrass
Multiflora Rose
 

Benthic Macroinvertebrates:
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Genus/Family Common Name Count
Gammarus Amphipod 35
Caecidotea Isopod 23
Parametriocnemus Non-Biting Midges 18
Thienemannimyia group Non-Biting Midges 14
Isoperla Stripetail Stonefly 10
Nemouridae Nemourid Stonefly 8
Tipula Crane Fly 6
Eccoptura Yellow Stone Stonefly 5
Prostoia Spring Stonefly 4
Clioperla Green-Winged Stonefly 4
Pycnopsyche Great Autumn Brown Sedge Caddisfly 3
Ptilostomis Giant Casemaker Caddisfly 2
Diplocladius Non-Biting Midges 2
Tanytarsini Non-Biting Midges 2
Zavrelimyia Non-Biting Midges 2
Limnephilidae Northern Casemaker Caddisfly 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.