Bering Sea, Aleutian Islands

The 1960s-70s was a period of high exploitation, particularly for yellowfin sole, Pacific ocean perch, walleye pollock. Since the 80s, the total allowable catch has been capped at 2 MT, which has been consistently lower than the sum of species quotas; so catch has been very stable and, while some species are considered fully exploited, the ecosystem has not shown patterns of overfishing. Over half of the total catch has been pollock, a mid-trophic level species. It also dominates the surveyed biomass, so the indicators tend to follow the variable recruitment of pollock, possibly explaining non-significant trends for 1996-2005. Longer-term positive trends in fish size and lifespan were due in part to longer-lived flatfish, which experienced strong recruitment in the 80s possibly due to beneficial climate conditions.

by Kerim Aydin, Sheila JJ Heymans
Table of Frequencies (percent)
Direction Fish size Trophic Level % Predators Life Span Biomass Stability % Sustainable Stocks
Fish size 0.584084 0.00 0.00 0.00 0.00 0.00
Trophic Level 0.00 0.628695 0.00 0.00 0.00 0.00
% Predators 0.00 0.00 0.442634 0.00 0.00 0.00
Life Span 0.00 0.00 0.00 0.556756 0.00 0.00
Biomass Stability 0.00 0.00 0.00 0.00 0.200155 0.00
% Sustainable Stocks 0.00 0.00 0.00 0.00 0.00 0.230273

Chla = Chlorophyll A (mg/m3)
SST = Sea Surface Temperature (°C)