MBSS Site Summary for: LOPC-206-R-2002

Site Photos

Located on CORKERS CR in the Lower Pocomoke River watershed, 8-digit code: 02130202.
This stream was visited in the spring on 3/11/2002 and again in the summer on 6/4/2002.

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 Fair - 3.3 / 5.0

Land Use

Land use can provide important information for determining stream health.
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Catchment area 5,087 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 1 %
Agricultural Land Use 49 %
Forested Land Use 48 %


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 8/20 (Marginal)
Velocity/Depth Diversity 3/20 (Poor)
Pool Quality
Pool Extent = 73 meters 		7/20 (Marginal)
Riffle Quality
Riffle Extent = 2 meters 		6/20 (Marginal)
Shading 97 %
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 19.7 ° C
Dissolved oxygen (DO) 4.1 mg/L
Dissolved oxygen levels measured in the stream were very low (4.1 mg/L). Many fishes and other aquatic animals cannot tolerate low levels of oxygen in the water.
pH (lab) 5.87
Conductivity 140 µmho/cm
Alkalinity
(acid neutralizing capacity) 		104.7 µeq/L
Dissolved organic carbon (DOC) 8.4 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 5 fish species were collected.
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Common name Count
Redfin Pickerel 44
Pirate Perch 27
Eastern Mudminnow 16
Bluegill 2
Golden Shiner 2
Biologists sampling fish communities.
Electrofishing to sample fish communities.

Amphibians and Reptiles:
Northern Green Frog

Crayfish:
No crayfish noted.

Exotic Plants:
Japanese Stiltgrass
 

Benthic Macroinvertebrates:
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Genus/Family Common Name Count
Tvetenia Non-Biting Midges 28
Simuliidae Black Fly 12
Crangonyx Amphipod 10
Parametriocnemus Non-Biting Midges 8
Hydrobaenus Midge 8
Dytiscidae Predaceous Diving Beetle 6
Stegopterna Black Fly 5
Diplocladius Non-Biting Midges 4
Pisidiidae Pill Clam 4
Menetus Air Breathing Freshwater Snail 3
Limnephilidae Northern Casemaker Caddisfly 3
Orthocladiinae Midge 3
Nemouridae Nemourid Stonefly 3
Conchapelopia Non-Biting Midges 2
Natarsia Non-Biting Midges 1
Procladius Non-Biting Midge 1
Corduliidae Emerald Dragonfly 1
Tabanidae Horse Fly 1
Caecidotea Isopod 1
Leptophlebiidae Pronggilled Mayfly 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.