MBSS Site Summary for: ASSA-104-X-2005


Located on Back Creek UT1 in the Assawoman Bay watershed, 8-digit code: 02130102.
This stream was visited in the spring on 4/21/2005 and again in the summer on 5/23/2005.

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 N R
Benthic IBI Poor - 1.0 / 5.0

Land Use

Land use can provide important information for determining stream health.
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Catchment area 9 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 93 %
Forested Land Use 1 %


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

Physical Stream Habitat
Instream Habitat 3/20 (Poor)
Epifaunal Substrate 2/20 (Poor)
Velocity/Depth Diversity 2/20 (Poor)
Pool Quality
Pool Extent = 39 meters 		3/20 (Poor)
Riffle Quality
Riffle Extent = 0 meters 		0/20 (Poor)
Shading 45 %
Embeddedness 100 %
The embeddedness, a measure of silt on the stream bottom, was 100%. This is very high, and may adversely affect biotic communities.
Several measures of instream habitat were considered 'Poor' at this location.


Stream Water Quality:
Water temperature 25.2 ° C
Dissolved oxygen (DO) 2.7 mg/L
Dissolved oxygen levels measured in the stream were very low (2.7 mg/L). Many fishes and other aquatic animals cannot tolerate low levels of oxygen in the water.
pH (lab) 6.96
Conductivity 11 µmho/cm
Alkalinity
(acid neutralizing capacity) 		2141.3 µeq/L
Dissolved organic carbon (DOC) 38.462 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:
Fish data is unavailable or no fish observed.

Amphibians and Reptiles:
Fowler's Toad

Crayfish:
No crayfish noted.

Exotic Plants:
Common Reed (Phragmites)
Japanese Honeysuckle
 

Benthic Macroinvertebrates:
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Genus/Family Common Name Count
Naididae Aquatic Worm 93
Tubificidae Aquatic Worm 5
Chironomus Non-Biting Midges 3
Limnoporus 1
Limnophyes Non-Biting Midge 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.