Spawning Observations 



The most complete and thorough series of spawning observations was 

 made in I9UI (Needham, Hanson, and Parker, 19h35 Parker and Hanson, 19Uli), 

 the year in which results of the experimental transfer of salmon to Deer 

 Creek were obtained. Throughout the spawning season of the spring-nan 

 fish, the creek was examined daily. 



The first prespawning activity was noted diaring the last week of 

 August near the lower falls. Intensive nest-building activities were 

 observed here the first week of September. In the Campbellville section, 

 nest building began at the close of the first week in September, In the 

 Apperson Ranch section, another week passed before any activity was noted, 

 and below this section no nest building was observed until the first week 

 of October. It was found that nest building activities commenced later 

 the farther downstream the salmon were located, and that these activities 

 did not commence until water temperatures had dropped sufficiently to 

 equal those found in the upstream sections. The actual spawning season 

 for the spring-riin fish lasted from September 10 to October 25. 



Subsequent observations in later years, while not as intensive, have 

 shown that spawning periods of the spring-run fish closely followed 

 those mentioned. In that portion of the creek above the lower falls now 

 available to salmon because of a fish ladder, nest building activities 

 and spawning usually begin the first week in September. By the end of 

 the spawning season in I9UI, a total of 1,U63 dead salmon had been 

 examined. The sex ratio in this sample was 1.65 males to 1 female. 

 During this period of observation, the average area of 87 salmon nests 

 measured in Deer Creek was U2 square feet. 



Nest building activities and spawning of the fall-run salmon in 

 Deer Creek occurs at a later date. Generally, this period for the fsill 

 fish is from the middle of October until the first of December. 



Downstream Migration of Young Salmon 



Sampling of the downstream migration of young salmon was started in 

 19i;l, but was not stabilized as to method, equipment, and site until the 

 early spring of 19U3. From that time on, sampling was uniform. The net 

 was fished in the same location, over approximately the same sf»ason 

 (January-June) and at the same time of 'day (night hours) each year. The 

 last 6 years of fyke-netting at the Deer Creek Station have produced 

 valuable information on the time of movements, peak periods, and size of 

 migrants. 



