An adaptive, rotational harvest strategy for data-poor fisheries on sedentary species: Application to the giant red sea cucumber (parastichopus californicus) in British Columbia

摘要

This research explores an adaptive rotational harvest strategy using animal size and population density as indicators for allowing harvest. Using sea cucumbers as a case study, I evaluate the relative yield and conservation performance of adaptive rotation and annual harvest strategies under a range of scenarios characterising uncertainty in population dynamics and localised harvest rates. In each scenario, the adaptive strategy achieves the rotation period that maximises long-term yield subject to conservation constraints. Under most scenarios and stochastic variability, adaptive rotation resulted in relatively higher spawning biomass and yield than annual harvest, which performed well only under assumptions of high productivity or low harvest rate. The adaptive strategy is robust to uncertainty in harvest rate and population dynamics, adjusting harvest frequency to meet recovery targets. I modelled the use of "insurance areas", or harvest reserves, to guard against there being no harvestable (recovered) areas under a system of adaptive rotation.