PROGRESS IN BIOLOGICAL INQUIRIES, 1934 387 



Data from the coastal stream steelhead studios started in 11)31 at 

 Scott and "Wadilcll Crocks and on the Klamath liivcr are rapidly 

 boin«:^ augmented. Tlie countin<^ weir constructed on AVaddell Creek 

 in 1933 has boon operated continuously since this time. 



During the winter season of lU33-t}-± at Waddell Creek, the spawn- 

 ing migration consisted of 478 steelhead and 538 silver salmon of 

 wliich liG3 and 213 were females, respectivel)'. The silver salmon 

 migration was largely coniinod to the last 2 weeks of December, while 

 the steelhead came in over a longer period which extended from Jan- 

 uary to the end of March. There was a considerable loss among the 

 steelhead due to disease, which was probably furunculosis and which 

 was associated with very low and w'arm water during March, April, 

 and May. Most of these fish died after spawning. In addition to 

 the adults moving upstream, 128 young fish varying in length from 

 /JO to 295 centimeters were taken in tlie upstream trap during the 

 months of December and January. These W'ere undoubtedly fish 

 which had spent the sinnmer in the closed lagoon, and some of the 

 larger were sexually mature males. The}' were given a distinctive 

 mark and passed on upstream. Later, 70 of these fish were taken on 

 their downstream migration with the other young steelhead. 



There were small numbers of downstream migrating steelhead dur- 

 ing December, January, and February, but the movement was great- 

 est during March and April, and from length frequencies it appears 

 that fish that had just completed their second year predominated. A 

 total of 3,117 3'oung steelhead were trapped and 2,452 of them marked 

 by the removal of the adipose and riglit pectoral fins. During June, 

 July, and August, a few fish of the year were taken in the trap each 

 "week. 



The downstream migration of young silver salmon {O. kisutch) 

 was much more concentrated than that of the young steelhead ; that 

 is, there was no scattering of fish previous and subsequent to the main 

 movement. The migration was also later, coming in April and May. 

 A total of 3,430 young salmon were taken, and 3,211 of them w'ere 

 marked by the removal of the adipose and right pectoral fins. 



An interesting discover}"^ was the fact that the two species of 

 cottoids inhabiting the stream {Gottus asper and C. gulosus), ap- 

 parently migrate downstream to spawn. During the period Decem- 

 ber to May, 3.357 of these fish w'ere taken in the downstream trap and 

 both males and females were approaching spawning condition as evi- 

 denced by the gonads. Although efforts were made to determine just 

 where they spawned, neither eggs nor fry were found. These cot- 

 toids are very destructive to young trout and salmon and this 

 annual period of migration may offer an opportunity to reduce their 

 numbers in such streams as it is felt desirable to do so. 



Work has been continued at Scott Creek on certain phases of the 

 artificial propagation of steelhead and, in conjunction Avith Waddell 

 Creek, on the homing instinct in these fish. The mouths of these two 

 streams are separated by only 5 miles of coastline and the annual 

 release of marked fish in each stream should make it possible to deter- 

 mine the degree of straying. It is becoming increasingly difficult to 

 secure a supply of steelhead eggs for the hatcheries without encroach- 

 ing on streams which are also heavily fished. Aji attempt is being 

 made at Scott Creek to build up this stream for egg taking and 



