MBSS Site Summary for: CN-N-051-202-96


Located on GRAVELLY BR in the Upper Choptank watershed, 8-digit code: 02130404.
This stream was visited in the spring on 3/11/1996 and again in the summer on 8/22/1996.

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 Fair - 3.7 / 5.0
Benthic IBI Poor - 2.7 / 5.0

Land Use

Land use can provide important information for determining stream health.
(Hint: Screen readers will announce definitions; mouse users can hover over dotted text.)
Catchment area 10,850 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 %
Agricultural Land Use 66.2 %
Forested Land Use 33.6 %


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 15/20 (Suboptimal)
Velocity/Depth Diversity 18/20 (Optimal)
Pool Quality
Pool Extent = meters 		15/20 (Suboptimal)
Riffle Quality 16/20 (Optimal)
Shading 75 %
Embeddedness 30 %
Several measures of instream habitat were considered 'Optimal' at this location.


Stream Water Quality:
Water temperature 19.3 ° C
Dissolved oxygen (DO) 9.7 mg/L
pH (lab) 6.6
Conductivity 141 µmho/cm
Alkalinity
(acid neutralizing capacity) 		165.4 µeq/L
Dissolved organic carbon (DOC) 5.8 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 16 fish species were collected.
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Common name Count
American Eel 16
Fallfish 8
Margined Madtom 6
Pumpkinseed 6
Redbreast Sunfish 6
Satinfin Shiner 6
Swallowtail Shiner 5
Tessellated Darter 4
Chain Pickerel 3
Pirate Perch 2
Redfin Pickerel 2
Rosyside Dace 2
Tadpole Madtom 2
Creek Chubsucker 1
Eastern Mudminnow 1
Yellow Perch 1
Biologists sampling fish communities.
Electrofishing to sample fish communities.

Amphibians and Reptiles:
American Bullfrog
Fowler's Toad
Northern Green Frog
Pickerel Frog
Wood 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
Prosimulium Black Fly 94
Strophopteryx Early Brown Stonefly 3
Prostoia Spring Stonefly 2
Oemopteryx Stonefly 2
Ephemerella Sulphur Mayfly 1
Parametriocnemus Non-Biting Midges 1
Micrasema 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.