MBSS Site Summary for: RKGR-404-R-2002

Site Photos

Field photo showing stream conditions at site RKGR-404-R-2002-1 (Opens in a new window) Field photo showing stream conditions at site RKGR-404-R-2002-2 (Opens in a new window)

Located on PATUXENT R in the Rocky Gorge Dam watershed, 8-digit code: 02131107.
This stream was visited in the spring on 3/20/2002 and again in the summer on 8/5/2002.

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 - 2.0 / 5.0

Land Use

Land use can provide important information for determining stream health.
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Catchment area 51,335 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 1 %
Agricultural Land Use 66 %
Forested Land Use 31 %


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 14/20 (Suboptimal)
Pool Quality
Pool Extent = 70 meters 		18/20 (Optimal)
Riffle Quality
Riffle Extent = 12 meters 		16/20 (Optimal)
Shading 72 %
Embeddedness 35 %
Several measures of instream habitat were considered 'Optimal' at this location.


Stream Water Quality:
Water temperature 22.6 ° C
Dissolved oxygen (DO) 5.6 mg/L
pH (lab) 7.36
Conductivity 160 µmho/cm
Alkalinity
(acid neutralizing capacity) 		480.1 µeq/L
Dissolved organic carbon (DOC) 2.1 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 18 fish species were collected.
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Common name Count
Tessellated Darter 65
Bluegill 63
Gizzard Shad 27
Largemouth Bass 25
White Sucker 15
Yellow Perch 15
Redbreast Sunfish 13
Northern Hogsucker 8
Margined Madtom 4
Blacknose Dace 3
Fallfish 3
Common Carp 2
Rosyside Dace 2
Yellow Bullhead 2
Black Crappie 1
Creek Chub 1
Longnose Dace 1
River Chub 1
Biologists sampling fish communities.
Electrofishing to sample fish communities.

Amphibians and Reptiles:
No amphibians and reptiles noted.

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
Hydropsyche Net-Spinning Caddisfly 19
Cheumatopsyche Net-Spinning Caddisfly 16
Rheosmittia Non-Biting Midges 14
Sphaerium Fingernail Clam 12
Conchapelopia Non-Biting Midges 7
Hemerodromia Tiny Fly 6
Orthocladius Non-Biting Midges 5
Rheocricotopus Non-Biting Midges 5
Glyptotendipes 5
Hyalella Amphipod 2
Tubificidae Aquatic Worm 2
Simulium Black Fly 2
Stenonema Flatheaded Mayfly 2
Dicrotendipes Non-Biting Midges 2
Nanocladius Non-Biting Midges 1
Brillia Non-Biting Midges 1
Girardia Freshwater Flatworm 1
Nigronia Megaloptera (Dark Fishfly) 1
Orthocladiinae Midge 1
Musculium Fingernail Clam 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.