00000nam 2200000za 4500 9.805224 CaOODSP 20221107135610 cr ||||||||||| 150406s1999 oncd ob f000 0 eng d eng fre n-cn--- Fs70-1/1999-107E-PDF Recent trends in the population of northwest Atlantic harp seals, Phoca groenlandica [electronic resource] / G.B. Stenson … [et al.]. Ottawa : Fisheries and Oceans Canada, 1999. 24 p. : fig., graphs, tables. Canadian Stock Assessment Secretariat research document, 1480-4883 ; 99/107 Includes bibliographical references (p. 10-13). Trends in the abundance of Northwest Atlantic harp seals for the period 1960 to 1998 were estimated using survey estimates pup production, and annual estimates of pregnancy rates and age structure of the catch. These data were fit to a two parameter age structured population model under two different assumptions of pup mortality. In one model formulation pup mortality was assumed to be equal to that of seals one year of age or older (1+) while in the second pup mortality rate was assumed to be 3 times the 1+ mortality rate. The uncertainty associated with the population trajectory from the first formulation was estimated by randomly resampling from within the sampling error of the available pup production estimates. Replacement and sustainable yields were estimated using both model formulations under differing assumptions of the age structure of the harvest. The impact of assuming different levels of unreported mortality on population trends was also examined. gccst Fisheries resources gccst Seals gccst Fishing area gccst Fisheries management Stenson, Garry B. (Garry Bruce), 1954- Canada. Department of Fisheries and Oceans. Canada. Canadian Stock Assessment Secretariat. Canadian Stock Assessment Secretariat research document, 1480-4883 ; 99/107 (CaOODSP)9.507740 PDF 2.07 MB https://publications.gc.ca/collections/collection_2015/mpo-dfo/Fs70-1-1999-107-eng.pdf CaOODSP eng