MBSS Site Summary for: PAXM-120-R-2001

Site Photos

Field photo showing stream conditions at site PAXM-120-R-2001-133 (Opens in a new window) Field photo showing stream conditions at site PAXM-120-R-2001-134 (Opens in a new window)

Located on LYONS CR in the Patuxent River middle watershed, 8-digit code: 02131102.
This stream was visited in the spring on 3/26/2001 and again in the summer on 7/31/2001.

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 - 3.0 / 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 1,372 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 3 %
Agricultural Land Use 67 %
Forested Land Use 28 %


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

Physical Stream Habitat
Instream Habitat 12/20 (Suboptimal)
Epifaunal Substrate 8/20 (Marginal)
Velocity/Depth Diversity 5/20 (Poor)
Pool Quality
Pool Extent = 75 meters 		8/20 (Marginal)
Riffle Quality
Riffle Extent = 0 meters 		0/20 (Poor)
Shading 90 %
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 19.2 ° C
Dissolved oxygen (DO) 8.3 mg/L
pH (lab) 6.79
Conductivity 190 µmho/cm
Alkalinity
(acid neutralizing capacity) 		168.5 µeq/L
Dissolved organic carbon (DOC) 2.8 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 7 fish species were collected.
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Common name Count
Eastern Mudminnow 431
Pirate Perch 35
Golden Shiner 25
Tessellated Darter 11
Creek Chubsucker 9
Pumpkinseed 6
Redfin Pickerel 6
Biologists sampling fish communities.
Electrofishing to sample fish communities.

Amphibians and Reptiles:
American Bullfrog
Eastern American Toad
Northern Green Frog
Southern Leopard Frog

Crayfish:
No crayfish noted.

Exotic Plants:
Japanese Honeysuckle
Multiflora Rose
 

Benthic Macroinvertebrates:
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Genus/Family Common Name Count
Cricotopus/Orthocladius Midge 43
Paratanytarsus Non-Biting Midges 11
Polypedilum Non-Biting Midges 10
Thienemanniella Non-Biting Midges 7
Rheosmittia Non-Biting Midges 6
Parametriocnemus Non-Biting Midges 5
Zavrelimyia Non-Biting Midges 5
Leptophlebia Pronggilled Mayfly 4
Conchapelopia Non-Biting Midges 4
Cricotopus Non-Biting Midges 2
Hyalella Amphipod 2
Caecidotea Isopod 2
Tanytarsus Non-Biting Midges 2
Stempellinella Non-Biting Midges 2
Rheocricotopus Non-Biting Midges 2
Tanypodinae Non-Biting Midges 1
Tvetenia Non-Biting Midges 1
Crangonyx Amphipod 1
Simuliidae Black Fly 1
Ablabesmyia Non-Biting Midge 1
Chironomini 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.