MBSS Site Summary for: PAXU-499-B-2012

Site Photos

Field photo showing stream conditions at site PAXU-499-B-2012-1 (Opens in a new window) Field photo showing stream conditions at site PAXU-499-B-2012-2 (Opens in a new window)

Located on PATUXENT RIVER in the Patuxent River upper watershed, 8-digit code: 02131104.
This stream was visited in the spring on 3/26/2012 and again in the summer on 7/6/2012.

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 - 3.7 / 5.0
Benthic IBI Poor - 2.3 / 5.0

Land Use

Land use can provide important information for determining stream health.
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Catchment area 84,976 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 13.9 %
Agricultural Land Use 43.1 %
Forested Land Use 38.9 %


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

Physical Stream Habitat
Instream Habitat 17/20 (Optimal)
Epifaunal Substrate 15/20 (Suboptimal)
Velocity/Depth Diversity 13/20 (Suboptimal)
Pool Quality
Pool Extent = 64 meters 		14/20 (Suboptimal)
Riffle Quality
Riffle Extent = 38 meters 		16/20 (Optimal)
Shading 40 %
Embeddedness 0 %


Stream Water Quality:
pH (lab) 7.46
Alkalinity
(acid neutralizing capacity) 		509.7 µeq/L
Dissolved organic carbon (DOC) 2.166 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 20 fish species were collected.
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Common name Count
Cutlip Minnow 136
Swallowtail Shiner 107
Tessellated Darter 105
Longnose Dace 87
Spottail Shiner 68
Fallfish 61
American Eel 60
White Sucker 58
Satinfin Shiner 49
Blacknose Dace 32
Green Sunfish 29
Redbreast Sunfish 18
Creek Chub 13
Creek Chubsucker 9
Golden Shiner 6
Bluegill 3
Yellow Perch 3
Pumpkinseed 1
Sea Lamprey 1
Yellow Bullhead 1
Biologists sampling fish communities.
Electrofishing to sample fish communities.

Amphibians and Reptiles:
American Bullfrog
Eastern American Toad
Gray Treefrog
Northern Green Frog
Pickerel Frog

Crayfish:
Orconectes limosus
Orconectes virilis

Exotic Plants:
Garlic Mustard
Japanese Barberry
Japanese Honeysuckle
Japanese Knotweed
Japanese Stiltgrass
Multiflora Rose
Oriental Bittersweet
Wineberry
 

Benthic Macroinvertebrates:
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Genus/Family Common Name Count
Orthocladius Non-Biting Midges 56
Cheumatopsyche Net-Spinning Caddisfly 19
Crangonyx Amphipod 14
Orthocladiinae Midge 5
Hydrobaenus Midge 4
Amphinemura Spring Stonefly 2
COENAGRIONIDAE Narrowwinged Damselfly 2
Physa Air-Breathing Freshwater Snail 2
Maccaffertium March Brown And Cahill Mayfly 2
Clinocera Aquatic Dance Fly 1
Simulium Black Fly 1
Musculium Fingernail Clam 1
Caecidotea Isopod 1
Ephemerella Sulphur Mayfly 1
Hydropsyche Net-Spinning Caddisfly 1
Microvelia Small Water Strider Beetle 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.