MBSS Site Summary for: PAXM-219-X-2006


Located on Swan Point Creek in the Patuxent River middle watershed, 8-digit code: 02131102.
This stream was visited in the spring on 3/21/2006 and again in the summer on 7/19/2006.

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 - 4.3 / 5.0
Benthic IBI Fair - 3.9 / 5.0

Land Use

Land use can provide important information for determining stream health.
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Catchment area 1,372 acres A stream flowing through a densely forested area. An example of a forested stream.
Urban Land Use 1 %
Agricultural Land Use 28 %
Forested Land Use 70 %


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

Physical Stream Habitat
Instream Habitat 11/20 (Suboptimal)
Epifaunal Substrate 7/20 (Marginal)
Velocity/Depth Diversity 11/20 (Suboptimal)
Pool Quality
Pool Extent = 68 meters 		12/20 (Suboptimal)
Riffle Quality
Riffle Extent = 7 meters 		12/20 (Suboptimal)
Shading 35 %
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) 8.7 mg/L
pH (lab) 6.86
Conductivity 151 µmho/cm
Alkalinity
(acid neutralizing capacity) 		241.2 µeq/L
Dissolved organic carbon (DOC) 2.5396 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 10 fish species were collected.
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Common name Count
Eastern Mudminnow 39
Blacknose Dace 19
Green Sunfish 14
Golden Shiner 8
Creek Chubsucker 7
American Eel 5
Tessellated Darter 4
Least Brook Lamprey 2
Eastern Mosquitofish 1
Pumpkinseed 1
Biologists sampling fish communities.
Electrofishing to sample fish communities.

Amphibians and Reptiles:
Common Five-Lined Skink
Northern Green Frog
Northern Watersnake

Crayfish:
No crayfish noted.

Exotic Plants:
Japanese Honeysuckle
Japanese Stiltgrass
Mile-A-Minute
 

Benthic Macroinvertebrates:
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Genus/Family Common Name Count
Orthocladius Non-Biting Midges 33
Parametriocnemus Non-Biting Midges 13
Thienemannimyia group Non-Biting Midges 12
Caecidotea Isopod 8
Bezzia Biting Midge 6
Gammarus Amphipod 3
Synurella Amphipod 3
Rheosmittia Non-Biting Midges 3
Tanytarsus Non-Biting Midges 2
Hydrobaenus Midge 2
Pseudolimnophila Crane Fly 2
Isotomurus Elongate-Bodied Springtail 2
Heterotrissocladius European Non-Biting Midge 2
Zavrelimyia Non-Biting Midges 2
Prostoia Spring Stonefly 2
Acerpenna Tiny Blue-Winged Olive Mayflies 2
Limnodrilus Worm 2
Leptophlebia Pronggilled Mayfly 1
Leptophlebiidae Pronggilled Mayfly 1
Musculium Fingernail Clam 1
Pycnopsyche Great Autumn Brown Sedge Caddisfly 1
Phylocentropus Caddisfly 1
Clinotanypus Non-Biting Midge 1
Apsectrotanypus Non-Biting Midges 1
Diplocladius Non-Biting Midges 1
Micropsectra Non-Biting Midges 1
Nanocladius Non-Biting Midges 1
Rheocricotopus 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.