Pattern and extent of spatmlng activity and its 



relation to certain stream characteristics 



In 19U7> 5^66U completed sea lamprey nests -vrere counted in 

 the Ocqueoc River. Of these, 2,763 or U8.9 percent were found 

 betireen the moiith of the river and the Ocqueoc Falls (Zone 1);, 

 and 133 or 2 =,3. percent -were foimd in Silver Creek and the Little 

 Ocqueoc River, tributaries of the main stream in this zone« In 

 Zone 2^ above the Ocqueoc Falls, 2,763 or US. 8 percent of the. 

 total were present. No spawning activity occurred in Zone 3 

 (Table 5). It is estimated from these figures, with due consi- 

 deration for the spaivning habits of the species, that between 

 10^000 and 11,000 sea lampreys spawned in the Ocqueoc River in 

 19U7. 



On the basis of a comparison of sample areas, it is con- 

 cluded that the distribution of spawning activity in I9U8 was 

 essentially the same althou^ there is some evidence that the 

 run was larger in this year than in 19U7. A comparison of sample 

 stations follows: 



Number of completed nests 

 Station 

 (and length of station) 19h7 1918 



(Below Ocqueoc Falls) ... ... 



Station IB (1,500 feet) 



Station IE (200 feet) 



Station IL-IM (256UO feet) 



(Above Ocqueoc Falls) 



Station 2E (700 feet) 



Station 2H (1,200 feet) 



Station 21 (iiOO feet) 



*Spawning activity in area completed, 

 l/count on July 3, 19U7. 

 2/Count on June 20, 19U7. 

 i/Coimt on J-une 28, 19U7. 



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