projections: Run simulations of a marine mammal population with bycatch...

In mcsiple/mmrefpoints: Project Marine Mammal Populations and Calculate Reference Points

Run simulations of a marine mammal population with bycatch mortality

Description

Generates several projections, stochasticity is in the number of catches from year to year

Usage

projections(
  NOut,
  ConstantBycatch = list(Catch = NA, CV = NA),
  ConstantRateBycatch = list(Rate = NA, CV = NA),
  InitDepl,
  lh.params,
  nyears,
  obs_CV = 0
)

Arguments

NOut	Number of simulations
ConstantBycatch	Mean and CV of number of animals killed as bycatch per year (assumed lognormal)
ConstantRateBycatch	Mean and CV of bycatch rate (assumed normal)
InitDepl	Initial depletion. If obs_CV>0, this is the mean depletion.
lh.params	Life history parameters as a list. The list must include S0, S1plus, K1plus, AgeMat, nages, z, and lambdaMax.
nyears	Number of years to do projections
obs_CV	Observation CV. Default to 1 for simple projections

Value

A list of outputs from simulations:

* params contains parameter values for each trajectory as a matrix;
* trajectories contains simulation outputs as a matrix;
* fishing.rates contain the bycatch rates for each year in each simulation as a matrix;
* InitDepl returns the initial depletion for the projections;
* ConstantBycatch provides Catch (total individuals killed in bycatch events per year) and CV of Catch (if the user has specified bycatch as a constant number);
* ConstantRateBycatch contains Bycatch Rate (additional mortality from bycatch each year) and CV of ByCatch rate. Other parameters are the same as in the dynamics() function.

Examples

projections(
  NOut = 3, ConstantRateBycatch = list(Rate = 0.01, CV = 0.3),
  InitDepl = 0.8,
  lh.params = list(
    S0 = 0.944, S1plus = 0.99,
    K1plus = 9000, AgeMat = 18, 
    nages = 20, z = 2.39, 
    lambdaMax = 1.02
  ),
  nyears = 50, obs_CV = 0
)

mcsiple/mmrefpoints documentation built on June 17, 2022, 8:41 p.m.