MBSS Site Summary for: CR-P-419-227-96


Located on GILLIS FALLS in the S Branch Patapsco watershed, 8-digit code: 02130908.
This stream was visited in the spring on 3/19/1996 and again in the summer on 7/23/1996.

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 - 4.3 / 5.0
Benthic IBI Fair - 3.0 / 5.0

Land Use

Land use can provide important information for determining stream health.
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Catchment area 6,171 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 73.1 %
Forested Land Use 25.4 %


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 17/20 (Optimal)
Velocity/Depth Diversity 16/20 (Optimal)
Pool Quality
Pool Extent = meters 		16/20 (Optimal)
Riffle Quality 16/20 (Optimal)
Shading 69 %
Embeddedness 15 %
Several measures of instream habitat were considered 'Optimal' at this location.


Stream Water Quality:
Water temperature 17.7 ° C
Dissolved oxygen (DO) 9.6 mg/L
pH (lab) 7.37
Conductivity 128 µmho/cm
Alkalinity
(acid neutralizing capacity) 		297.9 µeq/L
Dissolved organic carbon (DOC) 1.7 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 11 fish species were collected.
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Common name Count
Blue Ridge Sculpin 232
Rosyside Dace 132
Blacknose Dace 104
Common Shiner 36
Cutlip Minnow 32
Longnose Dace 28
White Sucker 21
Brown Trout 4
Central Stoneroller 3
River Chub 1
Tessellated Darter 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 79
Orthocladius Non-Biting Midges 26
Prostoia Spring Stonefly 2
Tanypodinae Non-Biting Midges 1
Baetidae Small Minnow Mayfly 1
Ephemerellidae Spiny Crawler Mayfly 1
Antocha Crane Fly 1
Tipula Crane Fly 1
Orthocladiinae Midge 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.