Part III.] Pond Fish Culture. 121 



Hatchery, at least, these fish do not spawn early. By spawn- 

 ing late these catfishes have the same natural advantages as 

 the Green sunfishes and the Bluegills. That is, they appear at 

 a time when the waters are warm and teeming with various 

 kinds of minute life which serves for their food. In this 

 respect the Black bass is at a disadvantage. These fish spawn 

 early, and great numbers of fish are brought into existence 

 before the water is warm enough to produce that abundance 

 of life that appears later on when the water is warmer. 



Food Habits. 



Catfish are omnivorous in their food habits. (See account 

 of food habits in Bulletin No. II.) The dissection of some of 

 the small and young Bullhead catfish went to show that they 

 are omnivorous in their food habits, the same as the larger 

 and older catfish. The whole catfish tribe seem to eat almost 

 anything edible they can find when food is scarce. However, 

 they prefer animal food, and ordinarily the greater part of the 

 food of the younger and smaller fish is made up of various 

 kinds of insects, mollusks, worms, crustaceans, and various 

 kinds of larvae. We' have dissected two or three bunches of 

 Bullhead catfish taken from the Ninnescah river, where animal 

 food was apparently plentiful, that did not have much of any- 

 thing in their stomachs except green vegetable matter. Small 

 water plants and pieces of plants made up the greater part of 

 the food contents of their stomachs, with a few small larvse, 

 worms and snails. This would seem to indicate that Bullhead 

 catfish sometimes eat vegetable food, even when much animal 

 life is present. Sunfish taken at the same time and from the 

 same water had their stomachs full of animal life. 



Not Cannibals, but Eat Other Fish. 



The Bullhead catfish do not eat their own kind, so far as our 

 observations go, at least until they are in a starving condition. 

 It is very seldom that we find a catfish has been eaten by 

 another catfish. We are speaking especially of the Bullhead 

 catfish family. The larger river "cats" spoken of in Part II 

 of this bulletin feed quite extensively on bullheads when they 

 can get them, and river fishermen use bullheads to bait trot- 

 lines for big river "cats." The food of specimens of bullheads 

 taken from the ponds here at the Hatchery is made up of dif- 

 ferent kinds of material, depending to a large extent upon the 

 season of the year, and, of course, the kinds of food material 

 that the ponds furnish. When food gets scarce, and sometimes 

 when it is not scarce, the bullheads will feed upon other fish. 

 We have found crappies, Bluegills and young bass in their 

 stomachs. They are not averse to feeding on other fish at any 

 time. However, we raise them here at the Hatchery with Blue- 

 gills and crappie, and, as a rule, we get a pretty good crop of 



