PROPAGATION AND DISTRIBUTION OF FOOD FISHES, 1932 561 



and development plan, authorized under the terms of the 5-year build- 

 inp; prop-am. This has included the construction of a concrete-lined 

 ditch over 1,500 feet lono; for the diversion of surface water, and the 

 construction of an additional pond approximating three-fourths of 

 an acre in area. It is noteworthy that this pond yielded in excess of 

 100,000 bass fry and fingerlings during the spring of 1932, and several 

 schools containing more than 8,000 fingerlings were taken. Enlarge- 

 ment and improvement of the station pond system is to be continued. 

 In addition to the propagation of shad, which was carried on in con- 

 junction with the State of South Carolina, the Orangeburg station 

 experimented in the use of abandoned rice fields for the rearing of 

 bass fry. Though many difficulties were encountered in this under- 

 taking, the results of the season's efforts were fairly satisfactory. 



Average success was attained in the fish-cultural work at the San 

 Marcos (Tex.) station and its auxiliaries at Fort Worth and New 

 Braimfels, Tex. The brood bream on hand were attacked by a 

 sudden epidemic, however, and all of them died \\dthin a space of 48 

 hours. Attempts made to renew the brood stock by the introduction 

 of fish from other points also resulted in a total mortality. The 

 nature and cause of this epidemic have not as yet been ascertained. 

 A large pond, constructed by erecting a dam in a slough of the San 

 Alarcos River, has not been a success, due to the fact that back- 

 water conditions produced stagnation, resulting in the loss of some 

 of the brood fish. In addition to its fish-cultural work the Fort 

 Worth substation is being used by the division of scientific inquiry 

 as a base for the experimental culture of mussels. A number of 

 tanks for the development of daphnia were installed there during the 

 year. The new substation at Natchitoches, La., had been practi- 

 cally completed by the close of the year and efforts were being made 

 to collect an adequate brood stock. At Tishomingo, Okla., gradually 

 increased production has been achieved from the improvements car- 

 ried on at this comparatively new station during the past year. 

 Tlie Fairport (Iowa) biological station, the center of investigation of 

 pond fish cultural methods, yielded a considerable number of fish, 

 amounting to four carloads. The majority of these were bass. 



RESCUE OPERATIONS AND UPPER MISSISSIPPI WILD LIFE REFUGE 



Administration of the Upper Mississippi Wild Life Refuge and the 

 bureau's Mississippi River salvage operations overlap, since a con- 

 siderable proportion of the area covered by the river crews falls 

 wdthin the boundaries of the refuge. The bureau's work in that 

 territory is centered at La Crosse, Wis., and field operations are car- 

 ried on during the rescue season from Homer, Minn., and several 

 other points. Due to a protracted water shortage, resulting from a 

 continuation of the drought of the previous year, there was a sharp 

 drop in the season's collections, the total of the 16 or more species 

 handled amounting to 51,611,367, representing less than half the 

 results of an average season. All of these fish were returned to 

 parental waters with the exception of 191,460, which were utilized 

 in the general distribution work. The greater part of the collections 

 were made in fields contiguous to the Homer substation. The cost 

 of the season's work amounted to 27 Ko cents per thousand fish 

 handled. 



