36 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 27 



of the canyons than on the nearby shelf. It has been suggested that fish 

 are concentrated in these areas because of the presence of abundant food 

 brought by currents from deep in the canyons. Many of the fish caught 

 from piers at the heads of Redondo and Newport canyons are species 

 characteristic of deep cold water, confirming the observation by some 

 skin divers that water may be colder at the head of a canyon than at 

 either side and that at times the water appears to be rising from the 

 canyon. A few current-meter measurements in six canyons of the area 

 (Shepard, Revelle, and Dietz, 1939) showed flows in the direction of 

 the canyon axes but with no preference for up or down canyon. Possibly 

 the water moves too slowly to be indicated reliably by such meters; a 

 better technique might be the measurement of properties of the water 

 itself. 



Two to eight water stations were occupied along the axes of most 

 of the 13 canyons at positions shown by open circles in Figure 3 through 

 15, Each station was positioned over the canyon axis by first making a 

 topographic profile and then by stopping the ship at such a position 

 that it would drift over the deepest point of the profile by the time that 

 water-sampling gear had been lowered. In a few instances the drift 

 varied so that the station was slightly to one side of the axis. Water 

 samples were collected in Nansen bottles carrying two protected re- 

 versing thermometers. In Redondo Canyon a series of four water samples 

 were obtained at each station just above the bottom through use of a 

 bottom water sampler described by Rittenberg, Emery, and Orr (1955). 



For each sample, temperature was corrected from the reversing ther- 

 mometers, salinity was computed from standard titration for chloride, 

 oxygen content was measured by Winkler analysis, and contents of sili- 

 cate, phosphate, and nitrate were determined by standard colorometric 

 methods using a Beckman DU spectrophotometer. The results are listed 

 in Table 1 for the eleven canyons which were sampled. Profiles of six 

 canyons with positions of water samples are presented in Figure 18, and 

 more completely with water characteristics for Redondo Canyon in 

 Figure 19. 



The measurements show no marked difference in the character of 

 the water at the canyon head from that near the seaward end of the 

 canyon. The water is also within the range of seasonal and areal varia- 

 tion of that in the adjacent basins (Emery, 1954). Close examination 

 of Table 1 and Figure 19, however, does show some slight inclination 



