Environmental Engineering Reference
In-Depth Information
Sturgeons (Acipen seridae); exLake
sturgeon ( Acipenser fulvescens )
North American catfishes (Ictaluridae);
ex. Channel catfish ( Ictalurus punctatus )
Minnows, carps and
suckers (Cypriniformes);
ex. Common carp,
( Cyprinus carpio )
Pikes (Esocidae); ex. Grass pickerel
( Esox americanus )
Sculpin (Cottidae); ex. Mottled
sculpin ( Cottus bairdi )
Trout and salmon (Salmoniformes); ex. Rainbow trout
( Oncorhynchus mykiss )
Order Perciformes (Temperate basses,
sunfish, perches, drums); ex. largemouth
bass ( Micropterus salmoides )
FIGURE 6.18 Freshwater ish by order. (Photographs from U.S. EPA, Biological indicators of watershed
health, Available at http://www.epa.gov/bioiweb1/html/ish_id.html.)
more commonly associated with low-order, colder streams and rivers, such as smallmouth bass and
trout. Fish such as catish and other species are commonly associated with higher-order streams, as
illustrated by the RCC (Figure 6.2).
Fish populations are adversely impacted by pollution, hydromodiication, and a variety of
other habitat modiications. Hydromodiication, such as channelization and dam construction, has
impacted ish populations in a number of ways. One impact of dams is changing the thermal regime,
both within and downstream of the dam, depending on the size of the dam and the dam operations.
For example, peaking hydropower facilities with the release of colder bottom waters have converted
many tailwater systems from warmwater to cold-water isheries.
Dams also have an impact as barriers to ish movement. Most commonly known are the impacts
of dams on the upstream movement of anadromous ish, those that live in the ocean and then repro-
duce in streams. Perhaps most widely known is the plight of Paciic salmon species. However, dams
impede the migration of other anadromous ish as well, such as the American shad, herring, striped
bass, and Atlantic sturgeon. There are also a number of freshwater ish that migrate up rivers and
tributaries to spawn, such as the white bass, and are adversely impacted by dams.
One of the stated goals of the Clean Water Act was to make the nation's waters “ishable and
swimmable.” One difference between ish and other indicator organisms is that often isheries
management is targeted toward speciic “ishable” or sports isheries, rather than native spe-
cies, such as artiicial stocking and ish management programs targeted toward ish species of
recreational importance. Examples include stocking programs for Florida bass, striped bass, and
the introduction of hybrids, such as white bass-striped bass hybrids, which sometimes occur at
the expense of species native to those stocked waters. The introduction of rainbow and brown
trout has resulted in dramatic declines of native brook trout and other species in some rivers and
streams.
Fish are commonly used as indicators of aquatic health. Grabarkiewicz and Davis (2008) describe
the importance and use of ish as biological indicators.
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