Risk management tools for sustainable fisheries management under changing climate: a sea cucumber example

Éva E. Plagányi, Timothy D. Skewes, Natalie A. Dowling and Malcolm Haddon

Online Resource 3

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Fig. 1 Comparison between a) model with no climate effects and b) model with climate effects

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Fig. 2 Reference Set model spawning biomass (t) projections for each of the species as indicated in each of the zones in which the species occurs, under no-fishing scenarios but with climate change effects. The alternative model versions differ in terms of choice of the natural mortality Ms (M), the steepness parameter hs of the stock-recruitment functions (H), whether both high risk only and high-plus-medium risk combined climate change scenarios are used (R) and the severity of the predicted impact of climate change on population variables (I).

Fig. 3 a-c Performance statistics for three different HS. Each panel shows the median (from 480 simulations) together with 90% probability interval for species 1 to 8, as per the key. The top plot is the 2031 spawning biomass for each species across the whole area, relative to the starting (1995) spawning biomass estimate. Below is the 2031 spawning biomass relative to the equivalent 2031 spawning biomass under a no-fishing scenario. The risk of falling below Blim is computed as the probability of the spawning biomass of each species dropping below a proxy level of 0.2*K during the projection period and across all areas and simulations. The second dotted line on the same plot is the risk of falling below Blim in any of the individual zones over the projection period, rather than when assessed across the species as a whole summed over all areas. The bottom plot shows the average catch (in tons gutted weight) for each species over the 20-yr projection period

Fig. 3 a-c Summary of performance statistics showing the estimated profit (in million US$) for each of the 8 model Zones and including all species, assuming the utility function per zone is as given by the solid line. The middle plots are the average annual catch (t gutted weight) summed across the whole area and with all species grouped according to their relative value (L = low; M = Medium; H = High; and VH = Very high). The bottom row of plots show the fishing proportion (F) for each species averaged across all zones where it occurs

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