7145 ‎(2)‎

• UCREFRP Catalog Number: 7145
• Author: Inslee, T. D.
• Title: Spawning of Razorback Suckers
• USFW Year: 1981.
• Copyright Material: NO

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specialized spa~ti*ning ponds can be developed.
Spawning in Flow-Throu h T e Pond
The fish placed in Pond D were observed over the rocks 12 days after
stocking. Observations with an under•~:ater viewer showed that some areas
had been cleaned as if nests were being prepared. There were cleaned areas
observed until March 31st but no eggs had been observed on the cleaned areas.
The fish ware left in the pond until about the middle of April before they
were moved to a holding pond,
This technique needs to be attempted next year with better quality fish
and during the time when the females appear to be the ripest. The rock bed
wiii need to be washed to remove settled :ilt and organic material. A problem
of-slime algae was encountered this year growing on rocks and pond bottom,
the use of a herbicide in the pond would greatly reduce this problem and
will aid in keeping the rocks clean.
Circular Tank Spawning
The use of circular tanks in conjunctions with injections of 2 mg carp
pituitary per pound of female brood fish appeared to be a technique that
would be successful. Nest preparation was evident after 24 hours. There
were eggs found in the ,tank with injected females after being in ttie tank
eight hours. Eggs were observed in the 2, 4, 8 and 16 cell stage. The
female fish were reinjected with carp pituitary 48 hours after the first
injection. The adult fish were removed after 46 hours in the spawning tank.
There appeared to be eggs deposited on at Least two of the four nights.
Spawning occured during the hours of darkness. There were indications of
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nest preparation in the control tank but no spawning oc'cured after 12 days.
When the fish were removed from each tank two females from the injected and
all three females in the control tank yielded a small amount of eggs when
stripped. These eggs all appeared to be overripe and could not be fertilized.
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