Marsh - Anadromous Fish Habitat
Anadromous Fish Habitat
A variety of biotic and physicochemical data should
be monitored at restored fish runs.
- Water temperature and current speed at the fishway should be
monitored regularly, especially during the duration of the run.
- Observations of water turbidity should be made regularly.
- Seasonal (summer) juvenile
fish surveys should be conducted that targets juveniles to
monitor yearly production and gain information on future adult
- Adult fish surveys
should be conducted in deeper water above the impediment or at
the base of the dam using gill nets.
- Observations and visual estimates of fish entering or leaving
fishways can be used to gauge fish migration.
Volunteers can often be used to gather data on fishway activity, flow
rates, water temperature, and turbidity. Careful monitoring is critical
in the first season following restoration of the fish run to identify
any problems with the design of the fishway.
Duration of Monitoring
Monitoring should be continued yearly until it is evident that a
sustainable fishery has been reestablished for the river or stream
in which the impediments have been removed or modified. Periodic
monitoring thereafter should be continued for the life of the fishway
in order to maintain the function of the fishway, and to keep long-term
records on water quality and flow patterns.
Concrete and aluminum fishways are durable and long lasting. Wood
construction, although less expensive initially, generally requires
more maintenance over the long term. Routine clearing of debris
from the fishway and quickly repairing any damage that may occur
The principles of Adaptive Management have been incorporated into
the administration of habitat restoration projects within a variety
of governmental funding authorities and programs (Thom
1997). Comprehensive, long-term monitoring is a component of adaptive
management, which relies on the accumulation of evidence (via long-term
monitoring) to support a decision that demands action. If established early in the project planning phase
and implemented during successive monitoring and management phases,
adaptive management can be a powerful method to systematically assess
and improve the performance of restored ecosystems (Thom 2000).
A well-designed restoration monitoring program will allow project
managers to detect deviation from projected results months, years,
or decades following construction. For example, yearly monitoring
of a waterway following installation of a fishway might reveal seasonal
water quality problems or episodic sedimentation events. The specific
design features of a fishway may require enhancement or modification
during successive years to optimize fish passage.
Monitoring data can be used by project managers to demonstrate
the ability of the project to meet stated goals and objectives.
This is especially important in promoting the benefits of fish run
restoration to funding agencies, potential partners or sponsors for
future restoration projects, and the general public. Finally, long-term
monitoring data allows managers to learn from early projects, and
avoid potential pitfalls in successive restoration efforts (Thom
and Wellman 1997).
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Thom, R.M. 1997. System-development matrix for adaptive management
of coastal ecosystem restoration projects. Ecological Engineering
Thom, R.M. 2000. Adaptive management of coastal ecosystem restoration
projects. Ecological Engineering 15:365-372.
Thom, R.M. and K.F. Wellman. 1997. Planning aquatic ecosystem restoration
monitoring programs. Evaluation of Environmental Investments Research
Program, U.S. Army Corps of Engineers Institute for Water Resources,
Alexandria VA. IWR Report 96-R-23.
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