MBSS Site Summary for: CR-P-086-313-96


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 7/16/1996.

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 Good - 4.0 / 5.0

Land Use

Land use can provide important information for determining stream health.
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Catchment area 12,157 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 72.4 %
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 16/20 (Optimal)
Epifaunal Substrate 16/20 (Optimal)
Velocity/Depth Diversity 17/20 (Optimal)
Pool Quality
Pool Extent = meters 		16/20 (Optimal)
Riffle Quality 18/20 (Optimal)
Shading 70 %
Embeddedness 20 %
Several measures of instream habitat were considered 'Optimal' at this location.


Stream Water Quality:
Water temperature 20.2 ° C
Dissolved oxygen (DO) 9.2 mg/L
pH (lab) 7.41
Conductivity 124 µmho/cm
Alkalinity
(acid neutralizing capacity) 		273.2 µeq/L
Dissolved organic carbon (DOC) 0.9 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
Blue Ridge Sculpin 243
Central Stoneroller 183
White Sucker 96
Common Shiner 80
Blacknose Dace 75
Cutlip Minnow 70
Rosyside Dace 45
Longnose Dace 21
River Chub 12
Largemouth Bass 9
Tessellated Darter 8
Northern Hogsucker 7
Bluegill 4
American Eel 1
Brown Bullhead 1
Fallfish 1
Lepomis Hybrid 1
Pumpkinseed 1
Biologists sampling fish communities.
Electrofishing to sample fish communities.

Amphibians and Reptiles:
Eastern Snapping Turtle
Northern Green 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 59
Cricotopus/Orthocladius Midge 10
Ephemerella Sulphur Mayfly 9
Strophopteryx Early Brown Stonefly 6
Stenonema Flatheaded Mayfly 2
Nemouridae Nemourid Stonefly 2
Amphinemura Spring Stonefly 2
Tipula Crane Fly 1
Cheumatopsyche Net-Spinning Caddisfly 1
Orthocladius Non-Biting Midges 1
Baetidae Small Minnow Mayfly 1
Ephemera Mayfly 1
Eurylophella Mayfly 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.