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

56 HAMILTON ET AL

smaller by day 14. At day 28, fish in the 8X treatment
had lighter coloration, and by day 63 showed little
feeding.
Fish activity determined from video recordings was
increased in razorback sucker in the 8X treatment at
30 days of exposure, whereas for bonytail it was re-
duced in the IX and 2X treatments (Table VII). There
was no effect on feeding behavior recorded by video
taping. Critical swimming speed in razorback sucker
was reduced in the 8X treatment at 60 and 90 days of
exposure, and for bony tail was reduced in the 8X and
16X treatments (Table VII).
Whole-body residues of copper, selenium, and zinc
at each period increased generally in a concentration-
response manner (Table VIII). For razorback sucker,
residues of copper, selenium, and zinc were lower in
fish in the IX, 2X, and 4X treatments at day 90
compared to day 30, which suggests that the inorganics
were being regulated. In the 8X and 16X treatments,
residues of the three inorganics were higher at day 90
than at day 30, which suggests that the fish had lost
their ability to regulate these elements. For bony tail,
the three inorganics were lower in the IX, 2X, 4X, and
8X treatments at day 90, and in the 16X treatment for
copper, compared to day 30, which suggests that they
were being regulated. In the 16X treatment residues of

selenium and zinc stayed the same, which suggests that
fish were not able to regulate the inorganics in a
manner similar to those in the lower exposure treat-
ments.

DISCUSSION

For razorback sucker and bony tail, adverse effects con-
sistently occurred in the 8X and 16X treatments at day
90. These results suggest that razorback sucker and
bony tail generally have similar sensitivities to the inor-
ganic mixture.
The toxic effects observed in the present study were
suggested in acute toxicity tests with the same species
and mixture of inorganics. Buhl and Hamilton (1996)
tested the same nine-inorganic mixture with young
Colorado squawfish, razorback sucker, and bony tail.
They found no difference in sensitivity of the three
species to the Ashley Creek mixture. They also com-
pared the 96 h LCsos for the Ashley Creek mixture
with the measured environmental concentrations to
derive margins of uncertainty, i.e., ratio of biological
effects concentration (96 h LCso) to environmental
concentration, of 12-32 for the three species. The low
margins of uncertainty, i.e., < 100, indicated to them

TABLE VI. Behavioral observations of razorback sucker and bonytail exposed to a
mixture of nine elements simulating Ashley Creek, Utah, in a reconstituted water
representing the Green River

Species

Day

Behavior

Razorback sucker

14
21

42
49

Bonytail

56
63
7

90% of 8X and 16X fish hyperactive.
90% of 16X fish darker coloration than other
treatments.
8X and 16X fish smaller than controls.
16X fish evenly distributed in aquaria; 3/4 of fish in
other treatments somewhat grouped, i.e., schooling
behavior.
10% of 16X fish lethargic.
20% of 16X fish show loss of equilibrium. 100%
of 16X fish not feeding and very light coloration.
8X fish not feeding.
8X fish less active than other lower treatments.
10% of l6X fish inactive, resting vertically on
screen material.
16X fish lighter coloration and nOticeably smaller
than controls.
16X fish feeding less intensely than other treatments.
8X and 16X fish have lighter coloration than other
treatments.
16X fish show little feeding.
16X fish unresponsive to disturbance.
8X fish show little feeding.

3
7

14

28

35
56
63