Spatial Choice and Fisheries Bycatch:
The Eastern Bering Sea Flatfish Fisheries
by
JOSHUA K. ABBOTT
Ph.D. Candidate
Department of Agricultural and Resource Economics
University of California, Davis
One Shields Avenue
Davis, CA 95616
abbott@primal.ucdavis.edu
and
James E. Wilen
Professor
Department of Agricultural and Resource Economics
University of California, Davis
One Shields Avenue
Davis, CA 95616
wilen@primal.ucdavis.edu
Corresponding author: Joshua K. Abbott
Abstract
The flatfish trawl fisheries of the Eastern Bering Sea have been plagued by bycatch issues.
Under the system of management used by the North Pacific Fisheries Management Council, the
bycatch of crab and halibut is strictly controlled by the use of aggregate limits on the amount of
these species that can be caught in a given season. Unfortunately, the spatial coincidence of
bycatch and flatfish species, the non-selectivity of trawl gear, and the perverse incentives arising
from the common quota system have lead to numerous premature season closures due to bycatch
species, resulting in significant economic losses. In response to these losses, the majority of
fishermen forged an agreement with a third-party contractor, Sea State Inc., to pool spatially and
temporally explicit bycatch data in a shared information system so that this data could then be
used on a near real-time basis to avoid bycatch “hot spots”. The participants have claimed
significant bycatch reductions from this system. However, the subsequent patterns of bycatch
rates have left some cause for doubt with some species actually showing increases in their
bycatch rates. Furthermore, the simultaneous regulatory establishment of closed areas for the
protection of crab species may deserve much of the credit for reduced crab bycatch.
To uncover fishermen’s incentives for bycatch avoidance and test the impact of Sea State and
spatial closures, we devise and estimate a random utility model of fishing location choice. This
model differs from those in the literature in that fishermen base their choice of location not only
on expected target catch, but also on the expected harvest of bycatch species, thus allowing us to
uncover the “shadow cost” of bycatch in the minds of fishermen. We estimate this model on an
unusually rich dataset obtained from the North Pacific Groundfish Observer Program that
records the repeated spatial choices of fishermen at the individual haul level over a 6-year period
spanning the implementation of Sea State. Results are preliminary, but they suggest that the
shadow costs of halibut and crab were quite low prior to Sea State and that the program had only
minimal positive impacts upon fishermen’s incentives to avoid bycatch. Instead, reductions in
bycatch appear to be largely attributable to improvements in the quality of information available
to fishermen through Sea State. Finally, the closure of an area for the avoidance of crab bycatch
appears to have caused an unforeseen increase in the bycatch of halibut due to the reduced ability
of fishermen to alter their blend of bycatch by their choice of fishing grounds.
Keywords: Bycatch, Spatial Behavior, Random Utility Model