MBSS Site Summary for: ROCK-204-R-2009

Site Photos

Field photo showing stream conditions at site ROCK-204-R-2009-1 (Opens in a new window) Field photo showing stream conditions at site ROCK-204-R-2009-2 (Opens in a new window)

Located on Rock Creek in the Rock Creek watershed, 8-digit code: 02140206.
This stream was visited in the spring on 4/2/2009 and again in the summer on 7/22/2009.

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 - 4.7 / 5.0

Land Use

Land use can provide important information for determining stream health.
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Catchment area 4,691 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 13.8 %
Agricultural Land Use 64.5 %
Forested Land Use 21.4 %


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

Physical Stream Habitat
Instream Habitat 17/20 (Optimal)
Epifaunal Substrate 16/20 (Optimal)
Velocity/Depth Diversity 15/20 (Suboptimal)
Pool Quality
Pool Extent = 58 meters 		15/20 (Suboptimal)
Riffle Quality
Riffle Extent = 38 meters 		16/20 (Optimal)
Shading 65 %
Embeddedness 30 %
Several measures of instream habitat were considered 'Optimal' at this location.


Stream Water Quality:
Water temperature 19.8 ° C
Dissolved oxygen (DO) 8.5 mg/L
pH (lab) 7.36
Conductivity 137 µmho/cm
Alkalinity
(acid neutralizing capacity) 		472.6 µeq/L
Dissolved organic carbon (DOC) 1.274 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 14 fish species were collected.
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Common name Count
Potomac Sculpin 126
Blacknose Dace 55
Longnose Dace 22
Rosyside Dace 21
Cutlip Minnow 19
Spottail Shiner 18
Tessellated Darter 13
White Sucker 12
Bluegill 8
Creek Chub 7
Brown Bullhead 6
Largemouth Bass 5
Yellow Bullhead 5
Bluntnose Minnow 1
Biologists sampling fish communities.
Electrofishing to sample fish communities.

Amphibians and Reptiles:
Eastern Box Turtle
Northern Green Frog

Crayfish:
Orconectes virilis

Exotic Plants:
Garlic Mustard
Japanese Barberry
Japanese Honeysuckle
Japanese Stiltgrass
Mile-A-Minute
Multiflora Rose
Shrub Honeysuckle
Tree Of Heaven
 

Benthic Macroinvertebrates:
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Genus/Family Common Name Count
Isonychia Slate Drake Mayfly 21
Amphinemura Spring Stonefly 18
Cheumatopsyche Net-Spinning Caddisfly 11
Parametriocnemus Non-Biting Midges 7
Ephemerella Sulphur Mayfly 7
Neophylax Caddisfly 6
Maccaffertium March Brown And Cahill Mayfly 6
Chimarra Fingernet Caddisfly 4
Polypedilum Non-Biting Midges 4
Rheocricotopus Non-Biting Midges 4
Ceratopsyche 3
Tvetenia Non-Biting Midges 3
Simulium Black Fly 2
Hydropsyche Net-Spinning Caddisfly 2
Cricotopus Non-Biting Midges 2
Paratanytarsus Non-Biting Midges 1
Rheotanytarsus Non-Biting Midges 1
Thienemannimyia Group Non-Biting Midges 1
Stenelmis Beetle 1
Antocha Crane Fly 1
Triaenodes Long-Horned Caddisfly 1
Nigronia Megaloptera (Dark Fishfly) 1
Orthocladiinae Midge 1
Perlodidae Perlodid Stonefly 1
Optioservus Riffle Beetle 1
Ferrissia Small Air-Breathing Freshwater Limpets 1
Ancyronyx Spider Riffle 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.