MBSS Site Summary for: PAXL-294-S-2008

Site Photos

Field photo showing stream conditions at site PAXL-294-S-2008-1 (Opens in a new window) Field photo showing stream conditions at site PAXL-294-S-2008-2 (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 3/3/2008 and again in the summer on 6/2/2008.

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 - 4.0 / 5.0
Benthic IBI Good - 4.1 / 5.0

Land Use

Land use can provide important information for determining stream health.
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Catchment area 3,723 acres A stream flowing through a densely forested area. An example of a forested stream.
Urban Land Use 3.6 %
Agricultural Land Use 30.9 %
Forested Land Use 62.6 %


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

Physical Stream Habitat
Instream Habitat 17/20 (Optimal)
Epifaunal Substrate 14/20 (Suboptimal)
Velocity/Depth Diversity 16/20 (Optimal)
Pool Quality
Pool Extent = 59 meters 		16/20 (Optimal)
Riffle Quality
Riffle Extent = 34 meters 		17/20 (Optimal)
Shading 80 %
Embeddedness 75 %
The embeddedness, a measure of silt on the stream bottom, was 75%. This is relatively high, and may exclude some biota.
Several measures of instream habitat were considered 'Optimal' at this location.


Stream Water Quality:
Water temperature 19 ° C
Dissolved oxygen (DO) 9.7 mg/L
pH (lab) 6.89
Conductivity 114 µmho/cm
Alkalinity
(acid neutralizing capacity) 		214.6 µeq/L
Dissolved organic carbon (DOC) 3.0858 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 9 fish species were collected.
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Common name Count
Blacknose Dace 34
Fallfish 23
American Eel 14
Tessellated Darter 14
Creek Chubsucker 6
Eastern Mudminnow 6
Sea Lamprey 5
Rosyside Dace 4
Tadpole Madtom 2
Biologists sampling fish communities.
Electrofishing to sample fish communities.

Amphibians and Reptiles:
Eastern Cricket Frog
Gray Treefrog
Northern Green Frog
Northern Two-Lined Salamander
Pickerel Frog

Crayfish:
Orconectes limosus

Exotic Plants:
Japanese Honeysuckle
Multiflora Rose
 

Benthic Macroinvertebrates:
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Genus/Family Common Name Count
Strophopteryx Early Brown Stonefly 29
Prostoia Spring Stonefly 14
Nemouridae Nemourid Stonefly 13
Prosimulium Black Fly 10
Isoperla Stripetail Stonefly 8
Tribelos Non-Biting Midges 4
Orthocladius Non-Biting Midges 3
Parametriocnemus Non-Biting Midges 3
Paratanytarsus Non-Biting Midges 2
Probezzia Biting Midges 2
Limnephilidae Northern Casemaker Caddisfly 2
Thienemannimyia Group Non-Biting Midges 2
Oulimnius Riffle Beetle 1
Capniidae Small Winter Stonefly 1
Ephemerella Sulphur Mayfly 1
Leuctra  Rolled-Winged Stonefly 1
Nigronia Megaloptera (Dark Fishfly) 1
Simuliidae Black Fly 1
Neophylax Caddisfly 1
Tipula Crane Fly 1
Ormosia Cranefly 1
Stempellinella Non-Biting Midges 1
Tanytarsus Non-Biting Midges 1
Tvetenia Non-Biting Midges 1
Zavrelimyia Non-Biting Midges 1
Paraphaenocladius Non-Biting Midges 1
Eukiefferiella 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.