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

Site Photos

Field photo showing stream conditions at site MPAX-206-R-2002-1 (Opens in a new window) Field photo showing stream conditions at site MPAX-206-R-2002-2 (Opens in a new window)

Located on MIDDLE PATUXENT R in the Middle Patuxent River watershed, 8-digit code: 02131106.
This stream was visited in the spring on 4/3/2002 and again in the summer on 6/6/2002.

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 Good - 4.0 / 5.0
Benthic IBI Fair - 3.3 / 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 2,326 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 4 %
Agricultural Land Use 87 %
Forested Land Use 7 %


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

Physical Stream Habitat
Instream Habitat 13/20 (Suboptimal)
Epifaunal Substrate 14/20 (Suboptimal)
Velocity/Depth Diversity 13/20 (Suboptimal)
Pool Quality
Pool Extent = 63 meters 		12/20 (Suboptimal)
Riffle Quality
Riffle Extent = 12 meters 		15/20 (Suboptimal)
Shading 80 %
Embeddedness 60 %
The embeddedness, a measure of silt on the stream bottom, was 60%. This is relatively high, and may exclude some biota.


Stream Water Quality:
Water temperature 19.1 ° C
Dissolved oxygen (DO) 8 mg/L
pH (lab) 7.07
Conductivity 210 µmho/cm
Alkalinity
(acid neutralizing capacity) 		355.4 µeq/L
Dissolved organic carbon (DOC) 1.8 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 14 fish species were collected.
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Common name Count
Blacknose Dace 239
Rosyside Dace 206
White Sucker 54
Tessellated Darter 48
Longnose Dace 28
Fallfish 21
Cutlip Minnow 17
Creek Chub 12
Bluegill 4
American Eel 3
Common Shiner 2
Largemouth Bass 2
Swallowtail Shiner 2
Satinfin Shiner 1
Biologists sampling fish communities.
Electrofishing to sample fish communities.

Amphibians and Reptiles:
Northern Two-Lined Salamander

Crayfish:
No crayfish noted.

Exotic Plants:
Japanese Honeysuckle
Japanese Stiltgrass
Mile-A-Minute
Multiflora Rose
 

Benthic Macroinvertebrates:
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Genus/Family Common Name Count
Orthocladius Non-Biting Midges 14
Oulimnius Riffle Beetle 9
Tanytarsus Non-Biting Midges 7
Cricotopus Non-Biting Midges 7
Cheumatopsyche Net-Spinning Caddisfly 7
Hydropsyche Net-Spinning Caddisfly 6
Chaetocladius Non-Biting Midges 4
Conchapelopia Non-Biting Midges 4
Ephemerella Sulphur Mayfly 4
Nanocladius Non-Biting Midges 4
Tribelos Non-Biting Midges 3
Parametriocnemus Non-Biting Midges 3
Labrundinia Non-Biting Midges 2
Heptageniidae Flathead Mayfly 2
Hemerodromia Tiny Fly 2
Amphinemura Spring Stonefly 2
Pisidiidae Pill Clam 1
Dubiraphia Riffle Beetle 1
Optioservus Riffle Beetle 1
Prostoma Freshwater Nemertean (Ribbon Worm) 1
Serratella Mayfly 1
Hydroptila Microcaddisfly 1
Helichus Beetle 1
Antocha Crane Fly 1
Polypedilum Non-Biting Midges 1
Rheosmittia Non-Biting Midges 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.