BREIWICK ET AL ; ESTIMATED INITIAL POPULATION SIZE OF BOWHEAD WHALE 



the current (1978) stock level given the same val- 

 ues of the other parameters (r - M)^^^, M, and t 

 (Figure 2, Table 3). Table 4 shows the initial stock 

 size estimates from Table 3 (1978 stock level of 



2,700) reexpressed as deviations from row and col- 

 umn medians. The magnitude and direction of 

 changes in the estimates as a function of the dif- 

 ferent parameter combinations indicate that in- 



2700 



1848 1856 1864 1872 1881 1889 1897 1905 1913 1921 1929 1937 1946 1954 1962 1970 1978 



SEASON 



Figure 2. — Population back projections (where M = 0.06, Lag = 5 yr, ( r - M)max ~ 0.03) which would theoretically result in current 

 stock sizes of 900, 1,500, and 2,700 bowhead whales according to the model (see text). 



Table 3. — Results of iterative solution of Equation (3). Initial stock size estimates (in thousands) for various 

 values of vital parameters (M, lag time, and maximum net recruitment rate) and 1978 stock level. 



849 



