MBSS Site Summary for: HO-P-068-231-96


Located on ROCKBURN BR in the Patapsco River L N Br watershed, 8-digit code: 02130906.
This stream was visited in the spring on 3/22/1996 and again in the summer on 6/4/1996.

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 - 4.0 / 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 1,893 acres A stream flowing through a densely forested area. An example of a forested stream.
Urban Land Use 1.9 %
Agricultural Land Use 46.6 %
Forested Land Use 51.3 %


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

Physical Stream Habitat
Instream Habitat 18/20 (Optimal)
Epifaunal Substrate 17/20 (Optimal)
Velocity/Depth Diversity 10/20 (Marginal)
Pool Quality
Pool Extent = meters 		17/20 (Optimal)
Riffle Quality 16/20 (Optimal)
Shading 70 %
Embeddedness 50 %
Several measures of instream habitat were considered 'Optimal' at this location.


Stream Water Quality:
Water temperature 16.4 ° C
Dissolved oxygen (DO) 9.9 mg/L
pH (lab) 7.33
Conductivity 192 µmho/cm
Alkalinity
(acid neutralizing capacity) 		709.6 µeq/L
Dissolved organic carbon (DOC) 2.2 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 6 fish species were collected.
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Common name Count
Blue Ridge Sculpin 127
Blacknose Dace 65
Longnose Dace 58
American Eel 39
Tessellated Darter 17
Rosyside Dace 4
Biologists sampling fish communities.
Electrofishing to sample fish communities.

Amphibians and Reptiles:
Northern Two-Lined Salamander
Pickerel Frog

Crayfish:
No crayfish noted.

Exotic Plants:
No exotic plants noted.
 

Benthic Macroinvertebrates:
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Genus/Family Common Name Count
Cricotopus/Orthocladius Midge 104
Prosimulium Black Fly 16
Ephemerella Sulphur Mayfly 7
Diamesa Bloodworm 2
Lanthus Clubtail Dragonfly 1
Rhyacophila Free-Living Caddisfly 1
Hemerodromia Tiny Fly 1
Nemouridae Nemourid Stonefly 1
Optioservus Riffle Beetle 1
Anchytarsus Beetle 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.