management: Management

In vquennessen/densityratio: Using Density Ratios to Help Manage Fisheries In And Around Marine Reserves

Management

Description

management calculates the next timestep's fishing effort allowed, given the control rule and estimated density ratio.

Usage

management(
  t,
  cr,
  fdr,
  E,
  DR,
  target_DR,
  floor_DR = 0.2,
  effort_inc_allowed = 0.1,
  Time1
)

Arguments

t	temporary numeric value, the current time step.
cr	temporary numeric value, the current control rule.
fdr	temporary numeric value, the current final target density ratio.
E	numeric array, the relative fishing effort displayed in each area, at each time step, under each control rule, and for each natural mortality estimate.
DR	numeric value, the calculated density ratio at a particular timestep and under a particular control rule.
target_DR	numeric value, the target density ratio, below which effort is allowed to increase, and above which effort is decreased for the next timestep.
floor_DR	numeric value, the density ratio below which effort is set back to 10% of the original value. Default value is 0.20.
effort_inc_allowed	numeric value, the percent increase allowed in effort if the density ratio is below the target density ratio, on the interval (0, 1). Default value is 0.10.
Time1	numeric value, the number of years to run the model before a marine reserve is implemented. Default value is 50.

Value

a numeric vector of fishing effort for the next timestep, under the specific control rule, with a specific estimate of natural mortality.

Examples

A = 5; TimeT = 70; CR = 6; FDR = 4
E <- array(rep(0.2, A*TimeT*CR*FDR), c(A, TimeT, CR, FDR))
management(t = 51, cr = 1, fdr = 1, E, DR = 0.8, target_DR = 0.6,
   floor_DR = 0.2, effort_inc_allowed = 0.10, Time1 = 50)

vquennessen/densityratio documentation built on Aug. 28, 2022, 5:36 p.m.