GLOSSARY 



The following terms used in fur seal re- 

 search and management on the Pribilof Islands 

 have special meanings or are not readily found 

 in standard dictionaries. 



Age Class Age group. Seals of the same age 

 (usually used when referring to seals 

 older than pups). See year class. 



At Time of Tagging (or Sampling) Phr as e s us ed 

 to qualify estimates of the population 

 based on (1) tag returns at various ages 

 or (2) sampling for a marked to unmarked 

 ratio in the summer of birth. In either 

 case, an estimate of the total number of 

 pups born in a given year would include 

 pups alive "at time of tagging" ("or 

 sampling") plus the number that died be- 

 fore tagging or sampling. 



Checkmark A notch, slit, hole, or other mark 

 made on a seal flipper when a tag is 

 applied, to insure later recognition of an 

 animal which has lost its tag. 



Clinch or Clinching The device or action by 

 which metal tags applied to seal flippers 

 are fastened. A metal point is inserted 

 through an opening in the opposite end of 

 the metal strip then bent over a narrow 

 band to form a closed ring (or tag). 



Drive The act of surrounding and moving 

 groups of seals on land from one location 

 to another. 



Escapement Seals that were not killed because 

 they were either too old, too large, or 

 were not available. 



Female Kill That part of the annual har- 

 vest devoted principally to the kill of 

 female seals, usually in August. See male 

 kill. 



General Breeding Season Organized breeding 

 beginning about mid-June and ending in 

 early August. Identifiable by the formation 

 of harems. A limited amount of breeding 

 also occurs after the break-up of the 

 harem structure. 



Hauling Grounds An area, usually near a rook- 

 ery, on which nonbreeding animals con- 

 gregate. 



Haul Out The act of seals moving from the 

 sea to a rookery or hauling grounds on 

 shore. 



Homing Tendency The inclination of seals to 

 return to the rookery where they were 

 born, that is, home rookery or rookery 

 of birth. Homing tendency is expressed 

 as a percentage by comparing the number 

 of tagged seals in a specific group that 

 were found on their natal rookery with 

 the number that were found on some other 

 rookery or island. 



Known-Age Applied to seals for which age is 

 definitely known because they bear an 

 inscribed tag or have a certain combina- 

 tion of tag scar and checkmark. 



Male Kill That part of the annual harvest de- 

 voted principally to the kill of male seals, 

 usually in late June, in July, and in early 

 August. See female kill. 



Marked Seals that have been tagged, sheared, 

 or otherwise artificially marked so that 

 they can be identified. 



Marked to Unmarked Ratio The number of 

 marked seals compared to the number 

 of unmarked seals, usually expressed as 

 a decimal fraction. Example, 5:20, ratio 

 .25. 



Mixed Areas Areas behind some of the rook- 

 eries on which few seals appear until 

 August, or after the general breeding 

 season. Seals using these areas at that 

 time may be a mixture of animals from 

 traditional hauling grounds and from the 

 rookery. 



Mortality Rate Percent of a year class dying 

 during a specific period. 



Pregnancy Rate Percent females that were 

 carrying or had borne pups in the year 

 examined. For example, the pregnancy 

 rate of 5-year-old females was 69 percent. 



Return The return or survival of seals from 

 a year class. For example, 10,000 3- 

 year-old seals from the I960 year class 

 returned in 1963. 



Round The sequence in which hauling grounds 

 on St. Paul Island are visited in order to 

 collect seals for harvest. Current practice 

 is to make a complete circuit or round of 

 the hauling grounds in 5 days, repeating 

 the procedure throughout the male kill. 

 The round system is not followed during 

 the female kill on St. Paul Island, nor 

 during the male and female kills on St. 

 George Island. 



Round-Up The act of surrounding and collecting 

 seals to be driven for harvest, tagging, 

 or other purposes. 



Tagged Describes a seal having an inscribed 

 metal tag or tags attached to one or more 

 of its flippers. 



Tag- Lost A term applied to a seal that is known 

 to have been tagged because of a check- 

 mark and, in some cases, a healed tag 

 scar. See tag scar. 



Tag Scar A hole or torn area near the usual 

 tag site on a seal's flipper. Tags fall out 

 because of poor clinching or wear and are 

 forcibly torn out by catching in rock 

 crevices or driftwood. Possibly some are 

 torn out by the tagged seal. 



Tagged to Untagged Ratio See marked to un- 

 marked ratio. 



Tag Lost to Tag Ratio The number of seals 

 that have lost tags as compared with the 

 number retaining tags. Usually expressed 

 as a decimal fraction. 



Year Class Group of seals born in the same 

 year. See age class. 



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