MBSS Site Summary for: PAXU-212-R-2004

Site Photos

Field photo showing stream conditions at site PAXU-212-R-2004-69 (Opens in a new window) Field photo showing stream conditions at site PAXU-212-R-2004-70 (Opens in a new window) Field photo showing stream conditions at site PAXU-212-R-2004-71 (Opens in a new window)

Located on STOCKETTS RUN in the Patuxent River upper watershed, 8-digit code: 02131104.
This stream was visited in the spring on 3/10/2004 and again in the summer on 7/1/2004.

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 Fair - 3.3 / 5.0
Benthic IBI Fair - 3.6 / 5.0

Land Use

Land use can provide important information for determining stream health.
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Catchment area 4,375 acres A stream flowing through a densely forested area. An example of a forested stream.
Urban Land Use 1 %
Agricultural Land Use 44 %
Forested Land Use 54 %


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

Physical Stream Habitat
Instream Habitat 16/20 (Optimal)
Epifaunal Substrate 13/20 (Suboptimal)
Velocity/Depth Diversity 15/20 (Suboptimal)
Pool Quality
Pool Extent = 40 meters 		14/20 (Suboptimal)
Riffle Quality
Riffle Extent = 35 meters 		12/20 (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 19.1 ° C
Dissolved oxygen (DO) 7.9 mg/L
pH (lab) 6.86
Conductivity 176 µmho/cm
Alkalinity
(acid neutralizing capacity) 		285.8 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 10 fish species were collected.
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Common name Count
Tessellated Darter 32
Blacknose Dace 30
American Eel 18
Green Sunfish 13
Least Brook Lamprey 4
Sea Lamprey 2
White Sucker 2
Eastern Mudminnow 1
Rosyside Dace 1
Satinfin Shiner 1
Biologists sampling fish communities.
Electrofishing to sample fish communities.

Amphibians and Reptiles:
American Bullfrog
Common Five-Lined Skink
Eastern Red-Backed Salamander
Gray Treefrog
Northern Green Frog
Northern Ring-Necked Snake
Northern Spring Peeper
Northern Two-Lined Salamander
Pickerel Frog
Southern Leopard Frog
Wood 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
Gammarus Amphipod 20
Parametriocnemus Non-Biting Midges 19
Isoperla Stripetail Stonefly 15
Prostoia Spring Stonefly 12
Strophopteryx Early Brown Stonefly 8
Tvetenia Non-Biting Midges 8
Synurella Amphipod 5
Capniidae Small Winter Stonefly 5
Prosimulium Black Fly 4
Tipula Crane Fly 4
Diplocladius Non-Biting Midges 3
Cheumatopsyche Net-Spinning Caddisfly 3
Thienemannimyia group Non-Biting Midges 3
Limnodrilus Worm 3
Polypedilum Non-Biting Midges 2
Oemopteryx Stonefly 2
Ephemerella Sulphur Mayfly 2
Acerpenna Tiny Blue-Winged Olive Mayflies 1
Rheosmittia Non-Biting Midges 1
Brillia Non-Biting Midges 1
Corynoneura Non-Biting Midges 1
Zavrelimyia Non-Biting Midges 1
Limnephilidae Northern Casemaker Caddisfly 1
Leptophlebiidae Pronggilled Mayfly 1
Stegopterna Black Fly 1
Ameletus Combmouthed Minnow Mayfly 1
Antocha Crane Fly 1
Enchytraeidae Aquatic Worm 1
Clioperla Green-Winged Stonefly 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.