Updated simulations of development in stock size and pup production for harp seals in the Greenland Sea 1946-1993, and corresponding catch and stock projections.

Applying the same model as in Ulltang (1989a, b), the development in stock size and pup production of the Greenland Sea hatp seal population is simulated for the period 1946-1993, assuming a pup production of 50000 in 1991 (minimum estimate adopted by the Working Group in 1991). A value of natural m...

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Bibliographic Details
Main Author: Ulltang, Øyvind
Format: Report
Language:unknown
Published: ICES 1993
Subjects:
Online Access:http://hdl.handle.net/11250/104533
Description
Summary:Applying the same model as in Ulltang (1989a, b), the development in stock size and pup production of the Greenland Sea hatp seal population is simulated for the period 1946-1993, assuming a pup production of 50000 in 1991 (minimum estimate adopted by the Working Group in 1991). A value of natural mortality M = 0.11 has been adopted, with natural mortality of age group 0 equal to 3M. Also the same maturity ogive (10% of 5 years old, 50% of 6 years old and 100% of 7 years old seals recruited to the breeding stock) and fertility rate (f=0.94) as used in earlier reports have been applied. Stock and catch predictions (Table 2) for 1994 are given for the same options as in earlier Working Group reports. For 1993, only Norwegian catches were known and included