Dall's porpoises apparently feed at night and depend to some degree 

 on the deep scattering layer. Based on studies in Monterey Bay, Dall's 

 porpoises are believed to be inactive during most of the day, perhaps 

 sleeping intermittently, and resuming active feeding in late atternoon. 

 In Southen California waters, the most common prey of Dall's 

 porpoises are lanternfish, squid, and small schooling fishes such as 

 anchovy, hake and jack mackerel. Apparent shifts in abundance and 

 distribution of Dall's porpoises off Southern California (southward 

 and inshore in autumn, especially near the northern Channel Islands, 

 and northward and offshore in late spring) may be largely due to 

 increased availability oi these prey species as well as to reduced water 

 temperature. 



Figure h- A Dall's porpoise on the bow ot a research vessel near San Miguel Island, January 1984 (top) and oft Point Conception, April 1980 : bottom). 

 Some Dall's porpoises appear to be resident around the northern Channel Islands and mav be seen at any time ot year. (Photo by S. Leatherwood ( top) 

 and G. Fnedrichsen (bottom).) 



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