MBSS Site Summary for: PAXM-122-R-2015

Site Photos

Field photo showing stream conditions at site PAXM-122-R-2015_Midpoint-looking-downstream (Opens in a new window) Field photo showing stream conditions at site PAXM-122-R-2015_Midpoint-looking-upstream (Opens in a new window)

Located on SWAN POINT BRANCH UT in the Patuxent River middle watershed, 8-digit code: 02131102.
This stream was visited in the spring on 3/30/2015 and again in the summer on 6/4/2015.

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 Good - 4.4 / 5.0

Land Use

Land use can provide important information for determining stream health.
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Catchment area 335 acres A highly channelized urban stream with concrete banks. An example of a highly channelized urban stream.
Urban Land Use 13.2 %
Agricultural Land Use 9.5 %
Forested Land Use 72.4 %


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

Physical Stream Habitat
Instream Habitat 9/20 (Marginal)
Epifaunal Substrate 10/20 (Marginal)
Velocity/Depth Diversity 7/20 (Marginal)
Pool Quality
Pool Extent = 22 meters 		7/20 (Marginal)
Riffle Quality
Riffle Extent = 53 meters 		9/20 (Marginal)
Shading 75 %
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:
pH (lab) 6.72
Alkalinity
(acid neutralizing capacity) 		295 µeq/L
Dissolved organic carbon (DOC) 2.2074 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 1 fish species were collected.
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Common name Count
Blacknose Dace 93
Biologists sampling fish communities.
Electrofishing to sample fish communities.

Amphibians and Reptiles:
No amphibians and reptiles noted.

Crayfish:
No crayfish noted.

Exotic Plants:
Garlic Mustard
Japanese Honeysuckle
Japanese Stiltgrass
Multiflora Rose
 

Benthic Macroinvertebrates:
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Genus/Family Common Name Count
Amphinemura Spring Stonefly 26
Gammarus Amphipod 18
Micropsectra Non-Biting Midges 13
Parametriocnemus Non-Biting Midges 9
Orthocladius Non-Biting Midges 6
Hydrobaenus Midge 6
Ironoquia Northern Caddisfly 4
Polypedilum Non-Biting Midges 3
Nanocladius Non-Biting Midges 3
Synurella Amphipod 3
Tipula Crane Fly 2
Rhyacophila Free-Living Caddisfly 2
Simuliidae Black Fly 2
Ameletus Combmouthed Minnow Mayfly 2
Orthocladiinae Midge 2
Diplocladius Non-Biting Midges 2
Rheocricotopus Non-Biting Midges 2
Limnephilidae Northern Casemaker Caddisfly 2
Caecidotea Isopod 2
Prostoia Spring Stonefly 2
Thienemannimyia Group Non-Biting Midges 1
Eukiefferiella Non-Biting Midges 1
Hexatoma Crane Fly 1
Siphlonurus Gray Drake Mayfly 1
Clioperla Green-Winged Stonefly 1
Tubificidae Aquatic Worm 1
Prosimulium Black Fly 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.