MBSS Site Summary for: ROCK-208-R-2003

Site Photos

Field photo showing stream conditions at site ROCK-208-R-2003-747 (Opens in a new window) Field photo showing stream conditions at site ROCK-208-R-2003-748 (Opens in a new window)

Located on NORTH BR ROCK CR in the Rock Creek watershed, 8-digit code: 02140206.
This stream was visited in the spring on 4/2/2003 and again in the summer on 7/15/2003.

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 Poor - 1.3 / 5.0

Land Use

Land use can provide important information for determining stream health.
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Catchment area 5,634 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 34 %
Agricultural Land Use 39 %
Forested Land Use 27 %


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 15/20 (Suboptimal)
Pool Quality
Pool Extent = 50 meters 		17/20 (Optimal)
Riffle Quality
Riffle Extent = 25 meters 		13/20 (Suboptimal)
Shading 85 %
Embeddedness 27 %


Stream Water Quality:
Water temperature 18.6 ° C
Dissolved oxygen (DO) 8 mg/L
pH (lab) 7.44
Conductivity 174 µmho/cm
Alkalinity
(acid neutralizing capacity) 		624.2 µeq/L
Dissolved organic carbon (DOC) 2.5 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
Potomac Sculpin 80
White Sucker 31
Tessellated Darter 20
Longnose Dace 19
Blacknose Dace 16
Bluegill 9
Bluntnose Minnow 7
Fallfish 5
Largemouth Bass 3
Spottail Shiner 3
Cutlip Minnow 1
Rosyside Dace 1
Silverjaw Minnow 1
Swallowtail Shiner 1
Biologists sampling fish communities.
Electrofishing to sample fish communities.

Amphibians and Reptiles:
Eastern Box Turtle
Northern Two-Lined Salamander
Pickerel Frog

Crayfish:
No crayfish noted.

Exotic Plants:
Japanese Honeysuckle
Japanese Stiltgrass
Mile-A-Minute
Multiflora Rose
 

Benthic Macroinvertebrates:
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Genus/Family Common Name Count
Hydrobaenus Midge 48
Orthocladius Non-Biting Midges 24
Diamesa Bloodworm 7
Ceratopogonidae Biting Midge 5
Hemerodromia Tiny Fly 4
Stenelmis Beetle 3
Prosimulium Black Fly 2
Orthocladiinae Midge 2
Stegopterna Black Fly 2
Parametriocnemus Non-Biting Midges 2
Paraphaenocladius Non-Biting Midges 1
Polypedilum Non-Biting Midges 1
Rheocricotopus Non-Biting Midges 1
Rheosmittia Non-Biting Midges 1
Oulimnius Riffle Beetle 1
Pisidium Freshwater Pea (Pill) Clam 1
Cheumatopsyche Net-Spinning Caddisfly 1
Cryptochironomus Non-Biting Midges 1
Simuliidae Black Fly 1
Tubificidae Aquatic Worm 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.