Allegheny River Headwaters Watershed Conservation Plan

Allegheny River Headwaters Conservation Plan
Chapter 4. Biological Resources
crop fields, and unpaved roadways will reduce the amount of sediments and contaminants introduced to
the streams (Walsh, Deeds, & Nightingale, 2007).
High Quality Large Stream Macroinvertebrate Community represents high-quality mid-reached
streams found in higher elevations with moderate gradients (Walsh, Deeds, & Nightingale, 2007). This
community type is typically located in high quality habitats and in highly forested catchments, while
urbanized development and agricultural operations are typically minimal. Water temperatures are cool,
and water chemistry values suggest some disturbances exist in the watershed, but do not indicate elevated
pollution levels.
Blue-winged olive dun mayfly, acentrellan mayfly, dark leadwinged olive mayfly, ephemerellid
mayfly, pale evening dun mayfly, fingernet caddisfly, netspinner caddisfly, and small minnow mayfly are
typical species found within this community. This community contains a biologically diverse assemblage
of organisms, of which many are intolerant of organic pollution (Walsh, Deeds, & Nightingale, 2007).
Threats to the High Quality Large Stream Macroinvertebrate Community increase as streams reach
valleys and urbanized areas. Pollution, habitat alteration, acidic precipitation, and increased levels of
sediment and nutrients from poorly managed buffers and agricultural areas can affect this community.
Streambank fencing and vegetated riparian buffer plantings can mitigate sedimentation and agricultural
runoff. Retention and treatment of any municipal discharges can help improve water quality and habitat
conditions (Walsh, Deeds, & Nightingale, 2007).
The Common Large Stream Community occurs in medium sized to large streams that maintain
fairly good water quality. These streams typically occur in high elevations with high gradients and high
quality in-stream habitats. Sections of stream within this community are often affected by disturbances,
such as non-point source pollution, that can cause excess sedimentation and could decrease water quality.
This community contains a diverse assemblage of organisms that has a relatively high richness.
Nemourid broadback stonefly, ameletid mayfly, taeniopterygid broadback stonefly are indicator species
for this community (Walsh, Deeds, & Nightingale, 2007).
Threats to this community come from agricultural operations, municipal point source pollution, and
urban stormwater effluents. Agricultural runoff and animal feed lots increase sedimentation; however,
implementing vegetative streambank buffers and livestock crossings can reduce sedimentation and
improve conditions. Mitigating stream discharges, such as stormwater runoff and point source sewage
effluents, through treatment and upgraded systems reduces pollution impacts on the streams habitat
(Walsh, Deeds, & Nightingale, 2007).
Mussel Communities
The Spike Mussel Community inhabits medium sized streams to large rivers that contain sand and
gravel substrate within riffle areas of fast moving and low gradient waterways. It is commonly found in
the larger tributaries to the Allegheny River, such as Potato Creek. Species that typify this community
include spike mussel and black sandshell. Other mussels, such as mucket, fatmucket, fluted-shell, and
pocket-book are also commonly found within this community, but are common in other communities, as
well (Walsh, Deeds, & Nightingale, 2007).
Habitats that support this community are often located in areas that have substantial agricultural
operations that likely impact the water quality. Managing agricultural runoff through the installation of
vegetative riparian buffers and riparian fencing should improve conditions. Strategies for retention of
stormwater and encouraging groundwater recharge could be applied where impervious surfaces create
runoff. Implementing additional proactive approaches to reducing sediment and nutrient loading that is
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