Table 42. — Live-pup counts, St. Paul Island, 

 1959-63 



Table 43. — Skins collected for experimental 

 use, St. Paul Island, 1958 and 1961-63 



changes only if several thousand pups are 

 involved and all the pups on the areas or 

 rookeries being used can be counted. 



The counts on the Tolstoi Rookery area and 

 on that part of Kitovi Rookery defined as 

 Blind to No. 13 will be discontinued because 

 these areas are not isolated from their respec- 

 tive rookeries. Counts of pups in Kitovi 

 amphitheater will be continued because this 

 area is separated from Kitovi Rookery by 

 natural barriers. Beginning in 1964, counts of 

 live pups will also be made on Little Polovina 

 and Zapadni Reef where a reasonably accurate 

 count can be made. 



Zapadni Reef and Little Polovina Rookeries 

 and Kitovi amphitheater contained 6.4 percent 

 of the total harem bulls counted on St. Paul 

 Island in 1963. An attempt will also be made 

 in 1964 to count the live pups on Zapadni and 

 Polovina Cliffs. These rookeries included an 

 additional 17.6 percent of the total harem 

 bulls counted on St. Paul Island in 1963. Com- 

 plete and accurate counts of live pups, in 

 addition to their value as a measure of popu- 

 lation changes, will be useful as a check on 

 the reliability of estimates of the pup popu- 

 lation made from marked to unmarked ratios. 



EXPERIMENTAL SKINS 



Several hundred skins have been collected 

 from fur seals for experimental use in re- 

 lating economic value to biological factors. 

 Table 43 summarizes the skins taken for 

 this purpose in recent years. 



Age, sex, reproductive condition, vibrissal 

 color, and body weight and length are the 

 biological attributes that have been com- 

 pared to the finished grade and size of the 

 corresponding skins. 



Experimental skins taken in 1958 and in 

 1961-62 have been routinely processed, graded, 

 and offered for sale as "blacks." Skins taken 

 in 1963 are still in process. Seals of smaller 

 and larger sizes not usually taken for com- 



mercial use were included in the experi- 

 mental kill. So far, the study has shown that 

 the skins of females ages 2-5 years have 

 good market value. The skins of females ages 

 6-15 years include about 90 percent "scarred" 

 or "rejected." Those good enough to process 

 have a market value equivalent to about 75 

 percent of that of the average male skin. 



Processors now state that the reasons why 

 female skins are of lower value than male 

 skins from seals of the same age are: 



1. Smaller size. 



2. Narrower distance betweenflipper holes, 

 giving a reduced area of fur. 



3. Thinner and silkier fur. 



4. More loss of fur by the manufacturer 

 when trimming the sides, because of mam- 

 mae. 



Male and female seals have approximately 

 the same number of fur bundles per unit area 

 and the same number of fibers per bundle. 

 The thinner fur of females must, therefore, 

 result from fibers of smaller diameter. Data 

 to demonstrate this difference have not been 

 collected. 



A full analysis of the experimental skins 

 taken in 1961-63 will be made in 1964. Mean- 

 while, a system of evaluating a skinby assign- 

 ing it an "index number" has been devised. 

 The index number is approximately the mean 

 sale value for each grade of black-dyed 

 bachelor skin over the past 10 years. Use 

 of the index number allows a quick evalua- 

 tion of a graded black-dyed skin without 

 knowledge of its ultimate sale value. The 

 actual sale value fluctuates with fashion and 

 may be difficult to extract from complex 

 auction data. The history of sales of female 

 skins is brief. More time will be needed to 

 develop an index value for them. 



DENTITION STUDIES 



A report describing the origin and growth of 

 the deciduous and permanent teeth of the fur 

 seal was completed. Co-authors were V. B. 

 Scheffer, Bureau of Commercial Fisheries, 

 and Bertram S. Kraus, Cleft Palate Research 

 Center, University of Pittsburgh. The report 

 will be published as a Fishery Bulletin by the 

 Bureau of Commercial Fisheries. 



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