MBSS Site Summary for: PAXL-112-R-2004

Site Photos

Field photo showing stream conditions at site PAXL-112-R-2004-1 (Opens in a new window) Field photo showing stream conditions at site PAXL-112-R-2004-2 (Opens in a new window)

Located on PATUXENT R UT 12 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 7/8/2004.

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 - 2.7 / 5.0
Benthic IBI Fair - 3.0 / 5.0

Land Use

Land use can provide important information for determining stream health.
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Catchment area 476 acres A stream flowing through a densely forested area. An example of a forested stream.
Urban Land Use 6 %
Agricultural Land Use 23 %
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 13/20 (Suboptimal)
Epifaunal Substrate 14/20 (Suboptimal)
Velocity/Depth Diversity 8/20 (Marginal)
Pool Quality
Pool Extent = 19 meters 		9/20 (Marginal)
Riffle Quality
Riffle Extent = 56 meters 		13/20 (Suboptimal)
Shading 96 %
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 22.2 ° C
Dissolved oxygen (DO) 6.9 mg/L
pH (lab) 7.4
Conductivity 246 µmho/cm
Alkalinity
(acid neutralizing capacity) 		1212 µeq/L
Dissolved organic carbon (DOC) 2.2 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 4 fish species were collected.
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Common name Count
Eastern Mudminnow 33
Blacknose Dace 23
Mummichog 6
Tessellated Darter 2
Biologists sampling fish communities.
Electrofishing to sample fish communities.

Amphibians and Reptiles:
Eastern Box Turtle
Northern Green Frog
Pickerel Frog
Southern Leopard Frog

Crayfish:
No crayfish noted.

Exotic Plants:
Japanese Honeysuckle
Japanese Stiltgrass
Multiflora Rose
 

Benthic Macroinvertebrates:
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Genus/Family Common Name Count
Caecidotea Isopod 83
Thienemannimyia group Non-Biting Midges 23
Capniidae Small Winter Stonefly 11
Orthocladius Non-Biting Midges 10
Parametriocnemus Non-Biting Midges 10
Diplocladius Non-Biting Midges 6
Leptophlebia Pronggilled Mayfly 2
Parachaetocladius Non-Biting Midge 2
Corynoneura Non-Biting Midges 2
Gammarus Amphipod 2
Lumbriculidae Worm 2
Tubificidae Aquatic Worm 1
Pseudolimnophila Crane Fly 1
Parakiefferiella European Non-Biting Midge 1
Orthocladiinae Midge 1
Nemouridae Nemourid Stonefly 1
Eukiefferiella Non-Biting Midges 1
Micropsectra Non-Biting Midges 1
Polypedilum Non-Biting Midges 1
Rheosmittia 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.