8285

• UCREFRP Catalog Number: 8285
• Author: Hamilton, S. J., K. J. Buhl, F. A. Bullard and E. E. Little.
• Title: Chronic Toxicity and Hazard Assessment of an Inorganic Mixture Simulating Irrigation Drainwater to Razorback Sucker and Bonytail.
• USFW Year: 2000.
• USFW - Doc Type: Yankton, South Dakota\
• Copyright Material: YES

SIMULATING IRRIGATION WATER TOXICITY 51

TABLE I. Mean (SE) of water quality characteristics in exposure aquaria during the exposure
of razorback sucker and bonytall to a mixture of nine elements simulating Ashley Creek,
Utah, In a recon.d80d water representing the Green River

Reconstituted water

Water quality characteristic

Razorback sucker

Bonytail

Green Rivera

pH
Hardness (mg/L as CaC03)
Alkalinity (mg/L as CaC03)
Conductivity (ILmhos/cm)
Calcium (mg/L)
Chloride (mg/L)
Sulfate (mg/L)
Un-ionized ammonia (mg/L)

a ReMillard et aI. (1989).

8.0
202(0)
106(0)
628(2)
48(0)
24(0)
162(1)
0.01(0)

were randomly stocked with 60 larvae and growth
chambers with 20 larvae each. Razorback sucker larvae
were 7 days old and bonytaillarvae were 6 days old at
stocking. Larvae were acclimated to the experimental
water for 2 days before the inorganic mixture was
introduced. Mortality was recorded daily and dead fish
removed. Growth was evaluated at 30 day intervals by
measuring total length and weight of individual fish
anesthetized with tricaine methanesulfonate. Water
temperature was maintained at 25 ::t 20e by placing the
aquaria in water baths warmed by recirculating, ther-
mostatically controlled water chillers. Fish were fed
Biodiet ad libitum at the rate of about 10% of their
average body weight per day, which exceeded standard
methods (Piper et al., 1982). The pellet size of the food
was increased as fish grew based on growth measure-
ments at 30 day intervals during the study. For the first
30 days of exposure larvae were fed live nauplii of
brine shrimp ad libitum..

Behavior Measurements

Fish in the residue chamber were monitored by visual
observation using a checklist for their general behavior
at weekly intervals, behavior was determined by video
taped recordings after 30 days of exposure, and swim-
ming performance was determined with a swimming
stamina tunnel after 60 and 90 days of exposure. Weekly
behavior measurements were conducted by the same
observer using a checklist of items including fish col-
oration, activity, excitability, location in aquaria, mode
of swimming, feeding, morphological, and other behav-
iors such as operculum movement, bites, and chases
(Little and DeLonay, 1996). The observer viewed the
fish in the residue chamber for a 2-3 min period prior
to feeding and 1- 2 min after feeding.
Video taping of behavior was accomplished by sus-
pending a video camera over the residue chamber of

8.0
202(1)
106(0)
632(3)
48(0)
25(1)
156(2)
0.02(0)

197
107

46
23
159

the exposure aquaria. Fish were not fed on the day of
video taping and disturbances of all fish were kept to a
minimum including temporarily turning off air stones.
About 1 h before video taping, an enclosure was placed
in the residue chamber and five fish were placed inside
the partitioned enclosure. Fish were allowed to accli-
mate to the enclosure for at least 30 min. After accli-
mation, fish behavior was recorded for 2 min, then fish
were fed, and feeding behavior was recorded for an
additional 5 min. Activity of individual fish was deter-
mined during playback of the video tape for a 1 min
period and was measured by counting the number of
times a fish crossed grid lines (Little and DeLonay,
1996). The lines were drawn on the monitor screen to
divide the video image into four equal quadrants. Thirty
seconds after the food was introduced, feeding behav-
ior was measured for 2 min by counting the number of
feeding strike movements each fish made toward the
food ration.
Swimming performance was determined using a 11.4
x 150 cm plexiglass stamina tunnel partitioned into
two test chambers. The pumping apparatus consisted of
a paddle wheel flow meter with digital readout, a 380 L
water supply tank, a constant speed 1.5 HP water
pump, and a gate valve. The water pump was controlled
by closing a gate valve while monitoring flow values on
a digital readout. The water used in the tests was the
same as in the toxicity tests and at the same tempera-
ture. Fish were not fed on the day of testing. Two fish
were each placed into the anterior and posterior cham-
bers of the tunnel for 5 min at a water velocity of 9.2
cm/min to ensure they would swim; thereafter, velocity
was increased by 6.2 cm/s every 3 min until the fish
were no longer able to swim. Two observers each
tracked the fish in the two chambers and recorded the
number of water velocities a fish swam and the time in
the last velocity when a fish stopped swimming and
rested against a restraining screen at the downstream