12 days after 15-second exposure 35 days after 20-second exposure 



72 days after 25-second exposure 4 months after 15-second exposure 



Figure 28. — Changes in cryogenic brands of the forearm pelage of fur seal pups, Zapadni Reef Rookery, St. Paul 



Island, 14 July to 14 November 1966. 



with the skin affect the uniformity of results. 

 We estimate that one thousand pups could be 

 marked per 8-hour day by using two men 

 for catching, two for restraining, one for 

 clipping, and one for branding. The use of 



six marking instruments would make a pre- 

 chilled instrument always available, and bat- 

 tery powered animal clippers could be used 

 in place of a gasoline generator. 



49 



