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Fishery Bulletin 118(4) 
MMB. 1, Was greater than MMB,, (Fig. 5B) but increased 
over time when MMB, .,;3, was equal to 0.5MMB,,; 
(Fig. 5D). The alternative of HR30 led to slightly higher 
catches but substantially higher effort when MMB, ;. 
was greater than MMB.,,. The alternative of HR10 led to 
lower catches than HR15, HR15U, and HR80. The alter- 
native of HR15U led to negligibly higher catches than 
HR15 (Fig. 5A). Results were similar for scenario 1 when 
CPUE was assumed to be proportional to the square root 
of abundance (Suppl. Table 8) (online only). 
The probabilities of the stock of golden king crab in 
the Aleutian Islands being overfished (MMB<MSST) and 
severely overfished (VUMB<0.5MSST) and of overfishing 
occurring (i.e., catch exceeding OFL) were zero, and the 
probability of this stock being below MMB,; was <0.02 
for all policies when MMB, ;, was greater than MMB;,; 
when CPUE was assumed to be linearly proportional 
to abundance (Table 4). The probability of this stock of 
golden crab being below MMB,, was higher for HR15, 
HR15U, and HR30 when CPUE was proportional to the 
square root of selected abundance, but the trends were 
similar to those with the linear relationship of CPUE to 
abundance (Suppl. Table 7) (online only). The fact that the 
probability of overfishing occurring was zero across poli- 
cies was expected, given the constraint that the predicted 
catch (in weight) in the directed fishery could not exceed 
the retained catch component of the ABC. Interestingly, 
the probabilities of the stock of golden king crab in the 
Aleutian Islands being severely overfished and of over- 
fishing occurring were also zero when the stock was ini- 
tially overfished. Probabilities of this stock being below 
MMB.,,, were greater for all policies when it was initially 
in an overfished state, yet probabilities of this stock stay- 
ing overfished during the projection period were <0.031 
for all policies, indicating a resiliency of this population 
in the simulations. 
Results from consideration of economic criteria for 
HRO were largely moot; therefore, only HR10, HR15, 
HR15U, and HR380 were ranked for these metrics. The 
alternative of HR10 resulted in lower catch in compari- 
son with that of the rest of the HCRs but led to improved 
performance for other economic metrics, such as reduced 
effort (i.e., fewer pot lifts needed to achieve a low TAC; 
see Tables 4 and 5 for the linear choice and Supplemen- 
tary Tables 7 and 8 [online only] for the nonlinear choice). 
Most economic criteria were similar between HR15 and 
HR15U for both initial conditions, indicating that the 
catch limit on legal-sized male abundance had little 
overall effect (see Table 5 for the linear choice and Sup- 
plementary Table 8 [online only] for the nonlinear choice). 
Table 4 
Conservation performance metrics for golden king crab (Lithodes aequispinus) in the Aleutian Islands, 
with the initial state of the stock set at healthy or overfished, for scenario 1 (based on best parameter esti- 
mates) of the operating model in which a linear relationship between catch per unit of effort and selected 
abundance is assumed. Values for the 5 harvest control rules (HCRs) evaluated by conservation criteria, 
HRO, HR10, HR15, HR15U, and HR30, are probabilities that the estimated quantity, such as mature male 
biomass (MMB) or total catch, is above or below the associated reference point, such as minimum stock 
size threshold (MSST), overfishing level (OFL), allowable biological catch (ABC), or 35% of the unfished 
level of MMB (MMB,,;), calculated for the last 10 years of the 30-year projection period, which begins with 
2018. For example, values for MMB<MSST are the probabilities that MMB is below MSST. Harvest control 
rules were ranked among each other for each performance metric (ranks are given in parentheses; ranks 
are the same for HCRs if probabilities are the same for those HCRs). Total catch is the catch retained in 
the directed pot fishery plus the discard mortality in the directed fishery and the bycatch mortality in the 
groundfish fishery. The stock is projected from 2 initial levels of abundance, measured in MMB: a healthy 
state (i.e., MMBoo13/MMB,,=1.55, where MMB.o1, is MMB in 2018) and an overfished state (i.e., MMBo91¢/ 
MMB,;=0.50). For details about the HCRs, see Table 1. Byjgy=the biomass corresponding to maximum sus- 
tainable yield. 
Metric 
Healthy 
Description HRO 
Overfished 
Severely overfished 
Overfishing (OFL) 
Overfishing (ABC) 
Below Bysy 
Overfished 
Overfished 
Severely overfished 
Overfishing (OFL) 
Overfishing (ABC) 
Below Bysy 
MMB<MSST 
MMB<0.5MSST 
Total catch>OFL 
Total catch>ABC 
MMB<MMB,, 
MMB<MSST 
MMB<0.5MSST 
Total catch>OFL 
Total catch>ABC 
MMB<MMB;, 
0.000 (1) 
0.000 (1) 
0.000 (1) 
0.000 (1) 
0.000 (1) 
0.000 (1) 
0.000 (1) 
0.000 (1) 
0.000 (1) 
0.000 (1) 
HR10 HR15 HR15U HR30 
0.000 (1) 
0.000 (1) 
0.000 (1) 
0.000 (1) 
0.001 (3) 
0.000 (1) 
0.000 (1) 
0.000 (1) 
0.000 (1) 
0.001 (3) 
0.000 (1) 
0.000 (1) 
0.000 (1) 
0.000 (1) 
0.016 (5) 
0.000 (1) 
0.000 (1) 
0.000 (1) 
0.000 (1) 
0.000 (1) 
0.000 (1) 
0.000 (1) 
0.000 (1) 
0.000 (1) 
0.063 (4) 
0.000 (1) 
0.000 (1) 
0.000 (1) 
0.000 (1) 
0.141 (5) 
0.000 (1) 
0.000 (1) 
0.000 (1) 
0.000 (1) 
0.000 (1) 
0.000 (1) 
0.000 (1) 
0.000 (1) 
0.000 (1) 
0.063 (3) 
