A Stochastic Dynamic Programming Model of Bycatch Control in Fisheries

Stochastic bycatch, informational asymmetry, and discarding

“…Each unit of biomass withdrawn is either retained (R) or discarded (D), so that R þ D ¼ W : All discarded stock is assumed lost from the system. 3 Total retained harvest on each trip in F i is constrained by a fishery-specific hold capacity R i : Though hold capacities are the same for all vessels in a fishery, effort (e) is not constant across vessel trips.…”

“…and total withdrawals by F 2 at time t are analogous to (3). System-wide withdrawals of X and Y in a given time period are W Xt ¼ W 1Xt þ W 2Xt and W Yt ¼ W 1Yt þ W 2Yt : Output from both fisheries is sold in competitive markets.…”

“…Subject to the fact that each vessel must undertake an integer number of trips 3. It is reasonable to assume that discards are ''removed'' from the system, given the high rate of mortality of discarded organisms in most cases.…”

Cyclical harvesting in fisheries with bycatch

“…Hoagland and Jin, 1997). In general, managing fisheries with bycatch using traditional harvest quota policies will be inefficient (Androkovich and Stollery, 1994;Abbott and Wilen, 2009;Holland, 2000).…”

“…However, only a few of these papers have examined these mechanisms using dynamic bioeconomic models (Ward, 1994;Androkovich and Stollery, 1994;Herrera, 2005;Skonhoft et al, 2012). Otherwise, there is presently little research that accounts for the role that stock dynamics play in managing a fishery with bycatch.…”