PROPAGATION AND DISTRIBUTION OF FOOD FISHES, 1923. 7T 



steady downpour of rain during May and early June, when the 

 distributions usually occur, roiled the pond water to such an extent 

 as to make the collection of fry impossible, and by the time the 

 water had begun to clear the schools of fish had broken up and be- 

 come dispersed among the dense vegetation in the ponds. Under 

 such conditions it became necessary' to carry over the entire crop for 

 distribution as fingerlings in the fall. 



An investigation conducted in May by the bureau's pathologist 

 disclosed the prevalence of a parasitic affection among the pond 

 fishes. The tapeworm {Proteocephalus amMopUtis) was found in 

 the sunfish and in both species of black bass, the larval stage of this 

 parasite heavily infesting the ovaries of some of the individuals, 

 examined. This trouble is believed to be one of the main causes 

 for the poor success heretofore attained in the pond fish-cultural 

 work at this station. So little is known of the nature of the organ- 

 ism, however, that prospects for its control do not seem bright, 

 and in view of the circumstances it may be found advisable to dis- 

 continue the efforts to produce the two species of black bass and 

 confine future activities in pond work to the propagation of the blue- 

 gill and green sunfish, which appear to be more resistant to the 

 ravages of the parasite than ^ny of the other species. 



A consignment of 7,800,000 yellow-perch eggs was received late 

 in March from the bureau's station at Bryans Point, Md. Of these 

 eggs 3,680,000 were turned over to the Missouri State hatchery at 

 Springfield, and from the remainder 3,500,000 fry were hatched and 

 distributed to applicants for that species. 



ROARING RIVER (MO.) SUBSTATION. 



Work in this field, which is about 50 miles east of Neosho, was 

 conducted on a share basis, the bureau receiving an equitable per- 

 centage of the eyed eggs obtained from the owner's stock of brood 

 trout. The Qgg collections, made between November 27 and Feb- 

 ruary 24, proved very disappointing, only 959,000, in round numbers, 

 being obtained from a brood stock large enough to have produced 

 at least twice that number. The small jdeld was attributed to 

 underfeeding of the fish, and as this was a factor over which the 

 bureau had no control, it was decided that the expense would not 

 justify the results in future operations and the agreement was ter- 

 minated at the end of the year. 



BOURBON (iro.) SUBSTATION. 



Bourbon is located in the eastern section of Missouri about 65 

 miles distant from St. Louis, and the property in which the bureau 

 is interested belongs to the von Hoffman Press Association of that 

 city. The cooperative arrangement entered into with this associa- 

 tion stipulates that the bureau shall provide the services of a man 

 to conduct fish-cultural work on the property, while the association 

 will bear all expenses of construction and maintenance of the plant, 

 including purchase of fish food and subsistence for the bureau's 

 employees. The bureau is to receive at least two-thirds of all finger- 

 ling fish produced, with the understanding that they are to be lib- 

 erated in Missouri waters. 



