MBSS Site Summary for: LOWI-115-R-2009

Site Photos

Field photo showing stream conditions at site LOWI-115-R-2009-1 (Opens in a new window) Field photo showing stream conditions at site LOWI-115-R-2009-2 (Opens in a new window)

Located on Horsebridge Creek in the Lower Wicomico River watershed, 8-digit code: 02130301.
This stream was visited in the spring on 3/24/2009 and again in the summer on 6/17/2009.

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 Poor - 2.7 / 5.0
Benthic IBI Poor - 2.4 / 5.0

Land Use

Land use can provide important information for determining stream health.
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Catchment area 3,812 acres A stream flowing through a densely forested area. An example of a forested stream.
Urban Land Use 6.5 %
Agricultural Land Use 42.7 %
Forested Land Use 47.9 %


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

Physical Stream Habitat
Instream Habitat 11/20 (Suboptimal)
Epifaunal Substrate 12/20 (Suboptimal)
Velocity/Depth Diversity 3/20 (Poor)
Pool Quality
Pool Extent = 75 meters 		10/20 (Marginal)
Riffle Quality
Riffle Extent = 0 meters 		0/20 (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 17.9 ° C
Dissolved oxygen (DO) 3.3 mg/L
Dissolved oxygen levels measured in the stream were very low (3.3 mg/L). Many fishes and other aquatic animals cannot tolerate low levels of oxygen in the water.
pH (lab) 5.94
Conductivity 118 µmho/cm
Alkalinity
(acid neutralizing capacity) 		177.8 µeq/L
Dissolved organic carbon (DOC) 6.4642 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
Redfin Pickerel 15
Eastern Mudminnow 14
Bluegill 13
Pumpkinseed 8
Chain Pickerel 2
Eastern Mosquitofish 1
Biologists sampling fish communities.
Electrofishing to sample fish communities.

Amphibians and Reptiles:
Northern Green Frog

Crayfish:
Cambarus diogenes

Exotic Plants:
Japanese Honeysuckle
Japanese Stiltgrass
Multiflora Rose
 

Benthic Macroinvertebrates:
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Genus/Family Common Name Count
Crangonyx Amphipod 44
Synurella Amphipod 17
Caecidotea Isopod 10
Hydrobaenus Midge 6
Orthocladius Non-Biting Midges 6
Musculium Fingernail Clam 4
Spirosperma Aquatic Oligochaete Worm 4
Tubificidae Aquatic Worm 3
Tipulidae Cranefly 2
Limnodrilus Worm 2
Ironoquia Northern Caddisfly 2
Rheocricotopus Non-Biting Midges 2
Zavrelimyia Non-Biting Midges 1
Paraphaenocladius Non-Biting Midges 1
Polypedilum Non-Biting Midges 1
Dytiscidae Predaceous Diving Beetle 1
Orthocladiinae Midge 1
Nemouridae Nemourid Stonefly 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.