MBSS Site Summary for: AA-N-092-225-97


Located on MIDWAY BR in the Little Patuxent River watershed, 8-digit code: 02131105.
This stream was visited in the spring on 3/31/1997 and again in the summer on 6/18/1997.

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 - 3.0 / 5.0
Benthic IBI Poor - 1.3 / 5.0

Land Use

Land use can provide important information for determining stream health.
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Catchment area 1,766 acres A highly channelized urban stream with concrete banks. An example of a highly channelized urban stream.
Urban Land Use 38.8 %
Agricultural Land Use 31.2 %
Forested Land Use 29.9 %


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

Physical Stream Habitat
Instream Habitat 6/20 (Marginal)
Epifaunal Substrate 11/20 (Suboptimal)
Velocity/Depth Diversity 15/20 (Suboptimal)
Pool Quality
Pool Extent = meters 		13/20 (Suboptimal)
Riffle Quality 14/20 (Suboptimal)
Shading 41 %
Embeddedness 26 %


Stream Water Quality:
Water temperature 17.2 ° C
Dissolved oxygen (DO) 11.1 mg/L
pH (lab) 6.87
Conductivity 282 µmho/cm
Alkalinity
(acid neutralizing capacity) 		614.5 µeq/L
Dissolved organic carbon (DOC) 6.3 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 7 fish species were collected.
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Common name Count
Blacknose Dace 401
Bluegill 15
Eastern Mudminnow 9
Least Brook Lamprey 7
American Eel 4
Pumpkinseed 4
Green Sunfish 1
Biologists sampling fish communities.
Electrofishing to sample fish communities.

Amphibians and Reptiles:
American Bullfrog
Eastern American Toad
Northern Green Frog

Crayfish:
Orconectes limosus
Orconectes virilis

Exotic Plants:
No exotic plants noted.
 

Benthic Macroinvertebrates:
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Genus/Family Common Name Count
Cricotopus/Orthocladius Midge 52
Orthocladiinae A Non-Biting Midges 36
Tanytarsus Non-Biting Midges 2
Simulium Black Fly 2
Limnodrilus Worm 2
Pisidium Freshwater Pea (Pill) Clam 1
Pseudosuccinea Air Breathing Freshwater Snail 1
Chelifera Aquatic Dance Fly 1
Boyeria Spotted Darner Dragonfly 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.