Broivn. — Pond Fishes. 185 



the eggs are nearing full development. About 35 pairs are 

 placed in an acre of water. 



An experiment in hatching bass eggs in a trough was 

 conducted at this station last spring. A nest of eggs found 

 on the morning of March 5, believed to have been spawned 

 the previous night, was taken up and counted and found to 

 contain about 4,500. They were placed in a trough of run- 

 ning water on a cheesecloth tray. They were showing the 

 eye spot on the 7th and the following day the outline of the 

 fry could be seen. Hatching began on the 9th and was 

 completed on the 10th. It was estimated from 600 to 800 

 fry were hatched. The yolk sac had all been absorbed by 

 the 23rd. They rose from the tray that morning and contin- 

 ued to maintain themselves as free swimmers thenceforth. 

 Beef heart was passed several times through an Enterprise 

 chopper and then rubbed through a cheesecloth screen. 

 Water was added to make a thin soupy solution. This was 

 spread over the surface of the water by the use of a feather. 

 The fry rose to it at once and took it greedily. On April 9 

 they were delivered to an applicant, being in all 394 advance 

 fry. 



In collecting advance fry for shipment advantage is 

 taken of the protective instinct of the male. He seems to 

 realize that by steering the fry near the shore he has only 

 one side of the school to protect from enemies. Close 

 observation is kept on the movements of the school and as 

 soon as they are old enough a cast-net is thrown over them 

 and the entire school, if possible, brought out. The ponds 

 should be carefully watched to locate schools before they 

 disperse, as a few fingerling bass can destroy an entire school 

 of advance fry in a short time. Proof of this was furnished 

 by a number 2 fingerling during the spring of 1922. A 

 school of advance fry were caught up and placed in a trough 

 for shipment. This fingerling was found among them with 

 a very much distended stomach. He was opened up and 

 found to contain 27 advance fry. Several of these were 

 digested, except the head, but with most of them the process 

 of digestion was only beginning. The loss through canni- 

 balism among fingerlings is far in excess of that of adults. 

 This shows the necessity of keeping in close touch with the 

 development of the fry, removing them for shipment before 

 they reach the fingerling stage. 



Sunfish, warmouth and crappie do not begin spawning as 

 early as bass. The fry are more susceptible to injury by the 

 net, and are more easily overcome with the heat. Hence, 

 they can not be successfully handled for shipment during 

 hot weather. They are left to be distributed during Octo- 



