K. R. Bestgen, K. A. Zelasko, and G. C. White. Monitoring ...

1997). A minimum of three sampling events per wetland in autumn and spring, including
overnight trap or fyke net sets, should be employed. Trammel nets should be used, but
judiciously, and perhaps with only short soak times (2 hr), given the potential presence of other
endangered fishes and mortalities that may occur with longer sets. If conditions permit and
efficiency is potentially high, other sampling gears including electrofishing or seining could also
be used.
Biological sampling in target wetlands should be accompanied by sampling for physicochemical
parameters as well. This is important because documented fish kills in floodplain
wetlands have been associated with poor water quality conditions in both summer and winter.
Minimally, measurements should include dissolved oxygen and water temperature, but other
parameters including pH, salinity and conductivity measurements may also be useful, and each
should be collected several times per day and year-round. Some wetlands are also known to
have elevated levels of selenium (e.g., Stewart Lake), which is being monitored sporadically
through a different U. S. Fish and Wildlife Service program. It may also be prudent to collect
some minimal level of information on the size and depth of the wetland habitats available. It
may be possible to monitor this relatively easily if staff-gauge depth measurements at known
elevations are linked with bathymetric maps of wetlands, if those data still accurately portray the
physical characteristics of the area (e.g., minimal sedimentation over time). These types of data,
when collected over several years, should yield insights into limiting parameters during various
flow (spring peak vs. baseflow) and climatic (warm summers, snowy winters which may induce
hypoxia) conditions.
Recognizing that equipment to continuously monitor floodplain wetlands is expensive
and that all wetlands in the middle Green River may not be suitable in all years to entrain and
support early life or older stages of razorback suckers, some areas should be given priority.
Selection of wetlands for monitoring should first focus on those that have supported early life
stages of razorback suckers in the past, and those with relatively low-elevation breaches that
flood relatively frequently (e.g., various Leota wetlands, Old Charley Wash, Stewart Lake;
Bestgen et al. 2011). Other locations that flood less frequently but have supported razorback
suckers in the past (e.g., Wyasket Lake, 2011), should also be monitored when fish are known to
inhabit the system to assist with interpretation of patterns of growth and survival. Other
wetlands should be monitored as equipment is available and appropriate conditions warrant (e.g.,
known entrainment of larvae, presence of other life stages). More comprehensive bathymetric
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