slide a blunt probe, such as a thin wire, over the genital
area toward the tail, with the point leading the probe.
Be cautious not to break the skin or penetrate the flesh
with the probe. If the point of the probe catches in the
genital opening, the fish is most likely a female. Draw-
ing the probe across the genital area in the opposite direc-
tion, from the tail side toward the head, should cause the
probe to catch on the genital papilla if the fish is a male.

Nutrition
 Good spawning success requires a proper diet for
brooders, especially in the fall and early spring months.
During warm weather feed a nutritionally complete diet
of about 35-40% protein at a concentration of 1-2% of
the stock body weight daily (Table 1). Catfish do not re-
quire feeding when water temperature falls below 50 F
(10 C). When water temperature is between 500 and 65 
F (10-18 C), feed approximately 0.50-0.75% of the
fishes' body weight three times per week. Estimate the
amount to feed by observing feeding vigor, if possible.
This can best be accomplished by using a floating pellet.
During warm weather, the proper amount of food to of-
fer is that which will be eaten in about 10 minutes.
Feeding activity declines when the spawning season begins
and during cold weather.
Table 1. Recommended brood fish diet.

Ingredient Percent of Total
Soybean meal (44% protein) 50.5
Ground corn 14.93
Wheat shorts 6.0
Distillers dried solubles 7.5
Fish meal 15.0
Animal fat 3.0
Pellet binder 2.5
Dicalcium phosphate 0.5
Vitamin premix 0.75
Coated vitamin C 0.057
Trace mineral mix 0.075

Analysis:
 Total crude protein 35.6%
 Digestible energy 2640 kcal/kg
 Energy to protein ratio (kcal/g) 7.3 : 1.0

 Stocking
 Total weight of brood fish should not exceed 1200
 pounds per acre at any time, hence ponds should be
 stocked initially at about 800 pounds of fish per surface
 acre to allow for weight gain. Successful spawners should
 gain about 50% of their weight from one spawning season
 to the next. Old, sick, and undesirable brood fish should
 be removed each spring and replaced with young brooders
 to maintain the total initial stocking density and to
 enhance vigor and productivity by reducing inbreeding.


 The most popular brood ponds in more northern states
are between 1 and 10 acres; smaller ponds may undergo
extreme temperature changes and reduce spawning suc-
cess, while larger ponds are difficult to manage. Problems
with pond construction, temperature control, and weed
management in Florida waters dictate that the most con-
venient size for brood ponds should be '/,o-l acre. Brood
fish should be stocked in more than one pond to minimize
the likelihood of wholesale destruction of an entire stock
from disease, oxygen depletion, or other catastrophes.

 Spawning Management

 Channel catfish begin spawning in late spring when
water temperature reaches about 75 oF (24 C). Males
prepare nests in hollow logs or similar shelters and ag-
gressively attack intruders. A female that is attracted to
a nest will mate with the male over a period of several
hours, depositing a large, yellow, jellylike egg mass. The
number of eggs laid is dependent on the size of the female
and averages around 2,000-3,000 per pound of body
weight. A one pound egg mass will contain about
10,000-11,000 eggs. After spawning, the male chases the
female away and guards the eggs. A single male may
spawn with more than one female in one season.

Use of Spawning Shelters
 Artificial spawning containers should be provided to
enhance spawning success and facilitate removal of eggs
and young. Commonly used items include milk cans, nail
kegs, ceramic or earthenware crocks, wooden boxes, am-
munition cans, and plastic or metal buckets and drums.
The spawning receptacle must be of sufficient size to ac-
commodate the brooding pair and should have an open-
ing just large enough for them to pass through. A hinged
lid will make it easier to check for spawning and to
remove eggs.
 Spawning containers should be provided for 50-90%
of the males, by placing containers in water 12-30 inches
deep, 1-10 yards apart, and with the opening toward the
pond center. Each nest container can be marked with a
float or flag to indicate its position.
 Containers should be placed in ponds at a time ap-
propriate for the target date of fingerling production.
Most spawning occurs at water temperatures between 75 
and 85' F (24'-30 C), with an optimum around 800 F
(27 C). Because of the large latitudinal temperature gra-
dient in Florida, channel catfish can be expected to spawn
at quite different times between about March and July
throughout the state. As a result, more southern farms
may have the greatest potential for supplying early seed
stock to markets in the north.
 Spawning activity sometimes diminishes for no ap-
 parent reason. Additional spawning may often be
 stimulated by lowering the water level of the pond about