MBSS Site Summary for: CR-P-086-325-96


Located on GILLIS FALLS in the S Branch Patapsco watershed, 8-digit code: 02130908.
This stream was visited in the spring on 3/13/1996 and again in the summer on 7/17/1996.

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 - 4.7 / 5.0
Benthic IBI Fair - 3.7 / 5.0

Land Use

Land use can provide important information for determining stream health.
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Catchment area 11,701 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 0.8 %
Agricultural Land Use 72.3 %
Forested Land Use 26 %


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

Physical Stream Habitat
Instream Habitat 15/20 (Suboptimal)
Epifaunal Substrate 16/20 (Optimal)
Velocity/Depth Diversity 17/20 (Optimal)
Pool Quality
Pool Extent = meters 		13/20 (Suboptimal)
Riffle Quality 18/20 (Optimal)
Shading 45 %
Embeddedness 10 %
Several measures of instream habitat were considered 'Optimal' at this location.


Stream Water Quality:
Water temperature 20.6 ° C
Dissolved oxygen (DO) 9.6 mg/L
pH (lab) 7.23
Conductivity 120 µmho/cm
Alkalinity
(acid neutralizing capacity) 		262.7 µeq/L
Dissolved organic carbon (DOC) 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 15 fish species were collected.
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Common name Count
Blue Ridge Sculpin 267
Central Stoneroller 151
Common Shiner 141
Blacknose Dace 75
Longnose Dace 38
Cutlip Minnow 35
Rosyside Dace 30
White Sucker 14
Northern Hogsucker 11
Rosyface Shiner 7
River Chub 6
Brown Trout 4
Tessellated Darter 4
Creek Chub 2
Largemouth Bass 1
Biologists sampling fish communities.
Electrofishing to sample fish communities.

Amphibians and Reptiles:
Eastern Box Turtle
Pickerel Frog

Crayfish:
Orconectes virilis

Exotic Plants:
No exotic plants noted.
 

Benthic Macroinvertebrates:
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Genus/Family Common Name Count
Prosimulium Black Fly 81
Strophopteryx Early Brown Stonefly 3
Chimarra Fingernet Caddisfly 2
Prostoia Spring Stonefly 2
Ephemerella Sulphur Mayfly 1
Stenonema Flatheaded Mayfly 1
Cheumatopsyche Net-Spinning Caddisfly 1
Orthocladius Non-Biting Midges 1
Amphinemura Spring Stonefly 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.