MBSS Site Summary for: PG-N-257-303-97


Located on HENSON CR in the Potomac River U tidal watershed, 8-digit code: 02140201.
This stream was visited in the spring on 3/11/1997 and again in the summer on 6/11/1997.

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 - 3.3 / 5.0
Benthic IBI Poor - 1.3 / 5.0

Land Use

Land use can provide important information for determining stream health.
(Hint: Screen readers will announce definitions; mouse users can hover over dotted text.)
Catchment area 11,641 acres A highly channelized urban stream with concrete banks. An example of a highly channelized urban stream.
Urban Land Use 52.1 %
Agricultural Land Use 12.3 %
Forested Land Use 32.9 %


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 11/20 (Suboptimal)
Velocity/Depth Diversity 15/20 (Suboptimal)
Pool Quality
Pool Extent = meters 		17/20 (Optimal)
Riffle Quality 12/20 (Suboptimal)
Shading 97 %
Embeddedness 45 %


Stream Water Quality:
Water temperature 17 ° C
Dissolved oxygen (DO) 8.6 mg/L
pH (lab) 7.44
Conductivity 280 µmho/cm
Alkalinity
(acid neutralizing capacity) 		837.8 µeq/L
Dissolved organic carbon (DOC) 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 14 fish species were collected.
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Common name Count
Blacknose Dace 65
American Eel 38
Longnose Dace 13
Tessellated Darter 13
Spottail Shiner 12
White Sucker 12
Redbreast Sunfish 11
Satinfin Shiner 10
Creek Chub 9
Pumpkinseed 8
Swallowtail Shiner 7
Mummichog 4
Bluegill 1
Creek Chubsucker 1
Biologists sampling fish communities.
Electrofishing to sample fish communities.

Amphibians and Reptiles:
Northern Green Frog

Crayfish:
Orconectes limosus

Exotic Plants:
No exotic plants noted.
 

Benthic Macroinvertebrates:
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Genus/Family Common Name Count
Rheocricotopus Non-Biting Midges 25
Cricotopus/Orthocladius Midge 12
Limnodrilus Worm 9
Parametriocnemus Non-Biting Midges 4
Enchytraeidae Aquatic Worm 3
Nematomorpha Horsehair Worm 2
Boyeria Spotted Darner Dragonfly 2
Hemerodromia Tiny Fly 1
Argia Narrow-Winged Damselfly 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.