662 U. S. BUREAU OF FISHERIES 



hand at the close of June, 1931. With the view of developing an egg-collecting 

 station near Highland, Mich., 600 adult rainbow trout were placed in a lake near 

 that point. Five cooperative trout nurseries were supplied with fish. In 

 advance of the spring spawning season the station brood stock of smallmouth 

 black bass was transferred from the pond where it had been held during the winter 

 to two brood ponds. At the close of the spawning season approximately 90,000 

 fry were collected from these inclosures and placed in three rearing ponds which 

 had been stocked previously with adult golden shiners to serve as a source of 

 food supply. A number of bass fingerlings produced during the spring of 1930 

 were distributed early in the fiscal year. Forty-eight goldfish were planted in 

 one of the ponds as an experiment in the production of forage fish. 



Charlevoix (Mich.) substation.— Lake trout, whitefish, brook trout, and steel- 

 head salmon were handled during the year at this substation. Eggs of whitefish 

 and lake trout, purchased from the commercial fishermen of the region, were 

 incubated in the station hatchery and the resulting fry were liberated on the 

 spawning grounds in the vicinity of the collecting points. In January 150,000 

 brook-trout eggs were received from the bureau's Craig Brook (Me.) hatchery. 

 The 146,250 fry resulting from this lot were distributed in near-by streams during 

 April, the Charlevoix Chamber of Commerce assisting in the work. The 26,700 

 steelhead salmon carried over from the previous year's activities were planted in 

 Lake Charlevoix in August by the Charlevoix Commercial Club. A lot of 34,200 

 two-inch fish of this species were reared from eggs received during the year and 

 planted in the above-named lake in the spring of 1931. 



Alpena (Mich.) substation.- — ^Lake trout and whitefish eggs are collected in a 

 number of fields near the Alpena station. Commercial fishermen strip the ripe 

 fish, sell the eggs to the bureau, and ship the fish to market for food. On delivery 

 to the station employees the eggs are transferred to the hatchery where the lake- 

 trout eggs are laid down in troughs and the whitefish eggs are installed in jars for 

 incubation. At the close of the hatching period the fry are distributed in the 

 vicinity of the collecting fields. 



The number of lake-trout and whitefish eggs collected during the year 1931 

 was disappointing. Chlorine in the water supply caused a heavy loss of whitefish 

 eggs, though the lake-trout eggs were not greatly afi'ected by it. During the 

 spring 246,000 one-inch fingerlings of the latter species were placed in a nursery 

 at Rogers City, Mich., and held until they had attained a length of 2 inches, at 

 which time they were planted. 



PUT IN BAY (OHIO) STATION 

 [David Davies, Superintendeat] 



Early in November arrangements were made with the commercial fishermen 

 for the collection of whitefish eggs. During the spawning season of this species, 

 extending from November 11 to the end of the first week in December, 144,300,000 

 eggs were secured. This number represented a 100 per cent increase as compared 

 with the take of the previous year and was the largest season's collection since 

 1923. The good results are attributable mainly to the unusually favorable 

 weather prevailing throughout the spawning period. Collections of pike perch 

 eggs were made between April 12 and May 4, the season's total amounting to 

 479,270,000, which was largely in excess of any year's total since 1911. The usual 

 collections of eggs of the yellow perch and carp were omitted in 1931. During 

 the early spring a number of adult smallmouth black bass were collected and 

 forwarded to the Northville (Mich.) station for replenishing the brood stock at 

 that point. 



In the course of the year the paint was burned and scraped from the pilot 

 house and boiler and engine rooms of the station steamer Shearwater, and the 

 entire boat was afterwards given three coats of paint. A new trough was 

 constructed and installed in battery No. 3. 



CAPE VINCENT (N. Y.) STATION AND SUBSTATIONS 



[J. P. Snyder, Superintendent] 



The four bass ponds partially built in the previous fiscal j-ear were completed. 

 These ponds were stocked in May with 500 adult smallmouth black bass. Near 

 the end of June a total of 81,400 advanced frj^ had been removed and placed in 

 public waters, and over 100,000 of the same size were awaiting shipment. Three 

 concrete daphnia ponds were constructed. 



