(2) watersheds should have forest cover and 

 terrain representative of southeastern Alaska; 



(3) streanns should contain populations of 

 salmon and resident trout; (4) streams and 

 watersheds should be small (to facilitate 

 environmental studies and to minimize the 

 cost of spraying); and (5) biological and 

 physical characteristics of the streams and 

 watersheds should be similar. 



Four watersheds meeting these criteria 

 were found at Skowl Arm, Prince of Wales 

 Island, near Ketchikan (fig. 1). The streams 

 were Cabin (Kl69,)^ Old Tom (K163), Saltery 

 Cove (K160), and Virginia (K171) Creeks, 

 Cabin and Virginia Creeks were designated 

 as test streams and Old Tom and Saltery 

 Cove Creeks as control streams. Each pair 

 includes a relatively large and a relatively 

 small stream in terms of physical size and 

 salmon production. The areas of their water- 

 sheds range from 7.8 to 28.5 km.^ (square 

 kilometers) (3 to 11 square miles). 



Each stream is relatively short, has one 

 or more small lakes in its drainage, and is 

 used by at least one species of salmon, sea- 

 run Dolly Varden ( Salvelinus malma ), rain- 

 bow trout ( Salmo gairdneri ), cutthroat trout 



The number in parenthesis is the stream designation 

 used in Orrell and Kllnkhart (1963). 



( S. clarki ), and prickly sculpin ( Cottus asper ). 

 Diptera (true flies) and Ephemeroptera (may- 

 flies) are the most abundant orders of insects 

 in the streams. 



Cabin Creek has the largest watershed, and 

 Orrell and Klinkhart (1963) reported maximum 

 spawning escapements of about 50,000 pink 

 salmon ( Oncorhynchus gorbuscha ) and 4,000 

 chum salmon (O. keta ). These species use 

 only the lower 365 m. (meters) of the streann 

 for spawning because a series of waterfalls 

 hinders their further migration. Small numbers 

 of sockeye salnnon (O. nerka ) and coho salmon 

 (O. kisutch ) ascend the falls, however, and 

 continue through Cabin Lake where they spawn 

 in the inlet. The lake contains rainbow and 

 cutthroat trout and immature coho and sockeye 

 salmon. 



Old Tom Creek has the largest salnnon 

 escapement of the four streams. It has had 

 maximum spawning escapements of about 

 285,000 pink salmon and 54,000 chum salmon 

 (Orrell and Klinkhart, 1963). Pink salmon 

 spawn in the intertidal area, the main stream, 

 and the west fork. Chum salmon use the main 

 stream and east fork. Rainbow trout and im- 

 mature coho salmon are abundant in the main 

 streann and the east fork. 



Saltery Cove Creek is accessible to anad- 

 romous fish only to its lower lake, about 0.4 km. 



2 3 4 5 6 7 8 

 KILOMETERS 



Figure 1. — Skowl Arm, Prince of Wales Island, southeastern Alaska, showing location of study. 



