MBSS Site Summary for: CA-S-089-201-97


Located on CHEW CR in the Patuxent River lower watershed, 8-digit code: 02131101.
This stream was visited in the spring on 3/17/1997 and again in the summer on 6/16/1997.

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 Fair - 3.7 / 5.0
Benthic IBI Fair - 3.6 / 5.0

Land Use

Land use can provide important information for determining stream health.
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Catchment area 1,991 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 22.6 %
Agricultural Land Use 41.3 %
Forested Land Use 35.7 %


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

Physical Stream Habitat
Instream Habitat 8/20 (Marginal)
Epifaunal Substrate 5/20 (Poor)
Velocity/Depth Diversity 9/20 (Marginal)
Pool Quality
Pool Extent = meters 		16/20 (Optimal)
Riffle Quality 4/20 (Poor)
Shading 75 %
Embeddedness 100 %
The embeddedness, a measure of silt on the stream bottom, was 100%. This is very high, and may adversely affect biotic communities.


Stream Water Quality:
Water temperature 14.7 ° C
Dissolved oxygen (DO) 10.7 mg/L
pH (lab) 7.17
Conductivity 206 µmho/cm
Alkalinity
(acid neutralizing capacity) 		577 µeq/L
Dissolved organic carbon (DOC) 2.1 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 8 fish species were collected.
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Common name Count
Tessellated Darter 23
Blacknose Dace 16
Bluegill 16
Fathead Minnow 10
American Eel 8
Eastern Mudminnow 6
Creek Chubsucker 3
Redfin Pickerel 2
Biologists sampling fish communities.
Electrofishing to sample fish communities.

Amphibians and Reptiles:
American Bullfrog
Eastern Box Turtle
Northern Spring Peeper
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
Crangonyx Amphipod 20
Ostracoda Seed Shrimp 14
Conchapelopia Non-Biting Midges 10
Caecidotea Isopod 10
Gammarus Amphipod 3
Polypedilum Non-Biting Midges 3
Zavrelimyia Non-Biting Midges 3
Perlodidae Perlodid Stonefly 2
Corynoneura Non-Biting Midges 2
Cheumatopsyche Net-Spinning Caddisfly 2
Stenonema Flatheaded Mayfly 2
Amphinemura Spring Stonefly 2
Hemerodromia Tiny Fly 2
Corixidae Water Boatman 1
Pseudosuccinea Air Breathing Freshwater Snail 1
Pycnopsyche Great Autumn Brown Sedge Caddisfly 1
Diplectrona Net-Spinning Caddisfly 1
Probezzia Biting Midges 1
Perlidae Common Stonefly 1
Hexatoma Crane Fly 1
Rheotanytarsus Non-Biting Midges 1
Thienemanniella Non-Biting Midges 1
Boyeria Spotted Darner Dragonfly 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.