14 



After planting the young salmon, a number of these two species were 

 caught daily, and the contents of their stomachs carefully examined. 

 Altogether only about twenty-five specimens,, of Cottus gidosas, of size 

 large enough to prey upon the young salmon, were caught. Out of 

 these twenty-five, not one had eaten a fish of any kind. Thirty or forty 

 specimens of Salmo gairdneri were examined daily for three weeks after 

 planting, and in not one instance had a salmon been eaten. The only 

 fish eaten by them was Rutilus symmetricus, and no more than ten of 

 these were found in about seven hundred examined. 



The other enemies to young fish observed were water snakes, king- 

 fishers, herons, and divers. Although none of these were killed to find 

 out what they were eating, it is safe to say that the loss of young salmon 

 due to them was slight. 



"PLANTING OF QUINNAT SALMON FRY IN MARIN COUNTY STREAMS IN 1898. 



In February, 1898, 2,000,000 Quinnat salmon fry were planted in 

 Paper Mill Creek and its tributaries by the United States Fish Com- 

 mission. On account of limited hatchery space and lack of funds, 

 the fry were all planted before the yolk sacs were absorbed. The fry 

 hatched at the same time as those liberated in these streams last year, 

 but they were planted about three weeks earlier. The height of the 

 water in the streams at the time of planting and during the next month 

 was lower in 1898 than in 1897. Notwithstanding this, the salmon ran 

 out earlier than the year before. In April there were not as many 

 salmon left in the streams as in June of the year before. In June no 

 salmon whatever could be found in Paper Mill Creek. Only a very few 

 were found in Olema Creek, and they were not much more plentiful in 

 Hatchery Creek the same condition that existed two months later in 

 1897. The only reason I can give for this difference in time of running 

 out is that they were planted at different ages. Apparently, planting 

 before the yolk sacs are absorbed causes them to run out earlier. This 

 brings up an important question : Does the holding of the fry until 

 after the yolk sacs are absorbed keep them from running out as soon as 

 they would under natural conditions ? 



From a series of specimens taken in April and June, it was found 

 that their average growth was .52 of an inch per month. It should be 

 noticed that this rate of growth during the first four months is almost 

 exactly the same as that found for the same period in 1897 differing 

 only .05 of an inch. 



