REPORT OF COMMISSIONER OF FISH AND FISHERIES. 83 



immense quantities of snow on the mountains, which not only retarded 

 the spawning season, but raised the streams to such an extent as to 

 practically stop work. Permission has been obtained from Mr. S. H. 

 Campbell, of the Wyoming Fish Commission, to operate next season 

 for brook trout in the vicinity of Laramie, where there are a number 

 of good streams. 



The Loch Leven trout eggs collected during the fall hatched in the 

 spring with a loss of only 2,450. The owner of the pond was given 

 8,000, and at the close of the year there were 27,000 on hand. 



The following table shows the stock at the station on June 30: 



Species. 



Calendar year in which fish were 

 hatched. 





1900. 



1899. 



1897. 



1896. 



Brook trout .... ._ ................. 



284,000 



27,000 



5,000 





300 



40 



154 



600 



Loch Leven trout 





100 



Black-spotted trout ................................. 



5,260 









Total 



316,000 



5,260 



494 



700 







BozEMAN Station, Montana (James A. Henshall, Superintendent). 



The freshet which occurred in June prevented the use of the creek 

 water for the grayling fry, and as many were dying i^n the hatching- 

 troughs, which are supplied by spring water of a low temperature, 

 300,000 were planted in Bridger Creek early in July. By the time 

 the rest of the fry were hatched the ponds were again supplied with the 

 creek water and they throve well in it, though the losses from canni- 

 balism were heavy. It would seem from the experience at this station 

 that the methods used in hatching and rearing trout are not entirely 

 applicable to the grayling. The fry can not be retained in troughs 

 supplied by cold spring water, as trout are. This is probably because 

 trout when first hatched have a large yolk-sac, which supplies them 

 with nourishment for a month or more, and by that time they are 

 able to take artificial food. The yolk-sac of the grayling is quite 

 small and is absorbed in a few days, consequently the fry have but little 

 •strength when they begin to swim and are apparently incapable of 

 taking artificial food, and as there is little or no natural food in 

 spring water, it is imperative that they be transferred to water con- 

 taining it. This food can easily be seen with the naked eye. In 

 holding a glassful to the light hundreds of small crustaceans (Ento- 

 mostraca), resembling specks of dust, can be seen floating in the 

 water. Another reason why the fry of the grayling should be trans- 

 ferred at an early stage to creek water is that they may get plenty of 

 sunlight, as they have been observed to be partial to the sunny parts 

 of the water. Within a week or two after the absorption of the sac 

 the fry learn to take finely chopped liver very readily. 



Operations at Jled Rock commenced much earlier than ever before, 

 collections of grayling eggs extending from April 30 to June 1. Mr. 

 G. H. Tolbert, who had charge of the work, secured 3,687,000; of 



