MBSS Site Summary for: MPAX-106-R-2007

Site Photos

Field photo showing stream conditions at site MPAX-106-R-2007-1 (Opens in a new window) Field photo showing stream conditions at site MPAX-106-R-2007-2 (Opens in a new window)

Located on Middle Patuxent River UT7 in the Middle Patuxent River watershed, 8-digit code: 02131106.
This stream was visited in the spring on 4/18/2007 and again in the summer on 6/12/2007.

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 Poor - 2.0 / 5.0

Land Use

Land use can provide important information for determining stream health.
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Catchment area 223 acres Cows standing in a stream at a site with high agricultural land use. Cows survey the sampling procedure at this extreme example of a highly agriculturalized site.
Urban Land Use 43.6 %
Agricultural Land Use 47 %
Forested Land Use 6.7 %


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 9/20 (Marginal)
Velocity/Depth Diversity 11/20 (Suboptimal)
Pool Quality
Pool Extent = 59 meters 		11/20 (Suboptimal)
Riffle Quality
Riffle Extent = 16 meters 		6/20 (Marginal)
Shading 95 %
Embeddedness 50 %


Stream Water Quality:
Water temperature 20.2 ° C
Dissolved oxygen (DO) 7.9 mg/L
pH (lab) 7.38
Conductivity 269 µmho/cm
Alkalinity
(acid neutralizing capacity) 		1044.2 µeq/L
Dissolved organic carbon (DOC) 5.0984 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 5 fish species were collected.
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Common name Count
Blacknose Dace 73
Bluegill 21
Rosyside Dace 6
Creek Chub 5
Largemouth Bass 1
Biologists sampling fish communities.
Electrofishing to sample fish communities.

Amphibians and Reptiles:
Eastern American Toad
Gray Treefrog
Northern Green Frog
Northern Spring Peeper
Pickerel Frog

Crayfish:
Cambarus diogenes
Orconectes virilis

Exotic Plants:
Japanese Honeysuckle
Japanese Stiltgrass
Multiflora Rose
Privet
 

Benthic Macroinvertebrates:
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Genus/Family Common Name Count
Crangonyx Amphipod 91
Naididae Aquatic Worm 38
Orthocladius Non-Biting Midges 8
Tanytarsus Non-Biting Midges 3
Tvetenia Non-Biting Midges 3
Lumbriculidae Worm 2
Polypedilum Non-Biting Midges 2
Rheosmittia Non-Biting Midges 1
Enchytraeidae Aquatic Worm 1
Tubificidae Aquatic Worm 1
Simuliidae Black Fly 1
Diamesa Bloodworm 1
Girardia Freshwater Flatworm 1
Diplectrona Net-Spinning Caddisfly 1
Chaetocladius Non-Biting Midges 1
Thienemannimyia group Non-Biting Midges 1
Menetus Air Breathing Freshwater Snail 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.