132 American Fisheries Society 



the sandy shallows; Indians dipping their long nets or erecting 

 wickerwork barriers ; fish-hawks and eagles all taking toll, combine 

 to make the ascent little less than a progress of decimation. 

 No one who has gazed into the foaming canyons of the Fraser 

 or Skeena rivers, 250 to 450 miles long; or canoed down the 

 Oweekayno river over four miles of furious torrent, or seen such 

 terrifying spectacles as the "Skookum Chuck" on the Lilloet 

 river below Tenas Lake, can fail to be amazed at the power of the 

 impulse which drives the fish through all these perils, and brings 

 the survivors at last to the pools and rippling shallows of the 

 distant spawning streams. These survivors show convincing 

 evidence of the dread ascent, for their bodies are torn by rough 

 stones, gashed by jutting rocks, maimed by jagged and precipitous 

 obstacles, or by falling, time after time, down almost impassable 

 falls. With fins and tails worn off or torn away, with jaws broken, 

 eyes missing, and with sides showing sores and fungused wounds, 

 they bear every evidence of incredible difficulties and disasters, 

 encountered on the laborious journey from the mouth of the 

 river. None of the usual explanations appear sufficient to account 

 for this irrepressible desire to reach remote waters, when lower 

 creeks and tributaries invite the salmon to enter. The fish pass 

 these, though they may appear ideal for the purpose sought, 

 just as an ordinary citizen passes a hundred other people's doors 

 in order to reach his own more distant door. 



Comparison With Bird Migration. 



The migrations of salmon and of birds have often been com- 

 pared. The annual flights of birds may extend over lands, seas, 

 deserts, and mountain ranges, and may even extend from one 

 hemisphere to another. Why, for example, do the vast flocks 

 of Godwit (Limosa uropygialis) go annually from beautiful New 

 Zealand to bleak and uninviting Siberia? The marvel about the 

 salmon's migration is this, that birds have keen sight and powers 

 of topographical recognition, but such acute vision and memory 

 cannot apply in the case of fish. Were the salmon able to remem- 

 ber the physical features of its native river mouth, the outflowing 

 current is so often beclouded with mud, and the contour of banks 

 and weed-covered rocks must change constantly, so that sub- 

 merged landmarks must be unreliable. Professor Arthur Thomson 



