CHINOOK SALMON MARKING, COLUMBIA RIVER 253 



Columbia River ports. Tliese records indicate that soiue of these fisli were to be 

 found within a short distance of the naouth of the Columbia during the entire fishing 

 season of each year. Recoveries from this district range in date from May to Sep- 

 tember. The two remaining records of recoveries in the ocean are from more remote 

 locahties. Both are from the west coast of Vancouver Island — ^one froni near 

 Barklcy Sound, taken on August 6, 1926, the other from near Ucluelet, British 

 Coliunbia, taken on August 9, 1926. These two recoveries agree with data obtained 

 from tagging experiments in showing that fish that will enter the Columbia River 

 during the fall may be found only a short time before at a considerable distance 

 up the coast. 



The data for the recoveries of 4-year-olds give the best indication of the time of 

 the spawning migration. Appearing first at the mouth of the Colimibia River 

 during the first week of August, these fish increased in abundance up to August 25, 

 when a closed season for commercial fishing cut off our records. When fishing was 

 resumed on Septemer 10 they were caught at the mouth of the river in even greater 

 nimibers than during August, and they appeared for the first tme in the vicinity of 

 Cascade Locks. About the middle of September the run began to drop oft", and by 

 the 1st of October the fish disappeared completely from the commercial fishery. 



The dates of recovery at Spring Creek give little indication of the time at which 

 the fish reach the creek, because most of them were not discovered until spawning 

 time. The hatchery records of the general run into Spring Creek are more reliable 

 for this purpose. These records show that the majority of the fish enter the creek 

 during September. Starting early in the month, about half of the run has passed 

 by the 20th and only a few come in after the 1st of October. The fish are nearly 

 ready to spawn at the time they enter the creek, but, in the absence of a gravel 

 bottom on which to spawn, they retain their eggs and sperm. This makes it possible 

 to delay the stripping process until most of the fish have matured. The bulk of the 

 eggs then are taken in one or two days. This restricted egg-taking period accounts 

 for the bunching of recoveries at Spring Creek. 



The data at hand indicate that most of the adult fish that escaped the com- 

 mercial fishery returned to Spring Creek to spawn. Eighty-two were recovered in 

 that creek, and only four are known to have chosen other tributaries. The records 

 from the commercial fishery of the upper Columbia are such that it is impossible to 

 determine whether the fish were caught above or below the mouth of Spring Creek, 

 but none was reported definitely from above that point, and one of the best fishermen 

 from that region has reported that he searched for marked salmon but found none. 

 Although a few of the fish have gone astray, there can be no question that most of 

 them sought and, if not previously captured, found the very small tributary from 

 whence they came. 



The scales of these adult marked fish present an interesting series of composite 

 nuclei, which, when studied as a group, offer no problems to one who is familiar with 

 scales of this type. To the inexperienced observer, however, the many incidental 

 checks that characterize this type would constitute a perplexing problem. A scale 

 that is representative of this collection is illustrated in Figures 75 and 76. The inner- 

 most 5 or 6 rings of this scale are slightly lighter and more closely spaced than those 

 immediately surrounding them. This portion of the scale corresponds exactly with 

 the entire scale of the fingerlings at the time of liberation. (See table 26 and fig. 74.) 

 At about 15 rings from the center a second break in the continuity of the rings (an 



