An evaluation of the annual quota mechanism as a management tool in the Mexican abalone fishery

Abalone constitute one of the most valuable natural resources on the west c oast of the Baja California Peninsula, Mexico. Because of its economic impo rtance, federal agencies and fishers' organizations have devoted special at tention to management of the abalone resource. Total allowable catch per co operative (TACCs) have been in effect since 1973. However, criteria for quo ta assessment have changed widely, over time, toward scientifically based m anagement. We review three quota criteria that have been considered during the history of the fishery: (1) constant exploitation rate; (2) prerecruitm ent index; and (3) dynamic model biomass estimations. We compare these resu lts with a newly proposed criterion derived from the Sinclair method. It se ems clear that, although TACC-based regulation may be considered the best o ption for management to date, great efforts should be made to reduce the di screpancy between different criteria. Moreover, it is our belief that befor e any further progress can be achieved regarding TACC management, a more co mplete understanding is required of the effects on abalone populations of f actors other than the fishery, such as the warm and cold water events, El N ino and La Nina.