openpop_ROC: An open population function to calculate population changes...

In katherinekaplan/MPApopulationmodels: Population responses to marine protected areas (MPAs)

Description

This function calculates the ratio change abundance and biomass of a fished poulation, after a marine protected area is implemented assuming a population with external recruitment. The output is a data frame with population ratio changes from a fished population to unfished in the MPA It includes deterministic population model output and output using stochastic recruitment

Usage

openpop_ROC(tf, maxage, M, Fi, Lfish, Linf, k, a0, pW, qW, R, sig_r, MPAtime,
  simulations)

Arguments

tf:	the time steps to run the population
maxage:	max age of the species ie. number of age classes
Lmat:	length at maturity
M:	the natural mortality rate
Fi:	the fishing mortality rate, F, find in stock assessment if don't have more localized estimate
Linf:	asymptotic growth rate used in von-Bertallanfy growth equation, can find on fishbase
k:	von-bertallanfy growth parameter estimate
a0:	the age at length 0 used in the von-Bertallanfy growth equation
pW:	weight length relationship parameter, same as a on fishbase.org but need to divide by 1000 to get in kg not grams
qW:	weight length relationship parameter, same as b on fishbase.org
R:	number of recruits entering the population
sig_r:	stochastic parameter, log-normal distribution, around recruitment
MPAtime:	the time step to implement the MPA
simulations:	the number of simulations to run

Value

roc2.a: returns the area under an reciever operating characteristic curve for abundance at year 2 since MPA implementation

roc5.a: returns the area under an reciever operating characteristic curve for abundance at year 5 since MPA implementation

roc10.a: returns the area under an reciever operating characteristic curve for abundance at year 10 since MPA implementation

roc20.a: returns the area under an reciever operating characteristic curve for abundance at year 20 since MPA implementation

roc2.b: returns the area under an reciever operating characteristic curve for biomass at year 2 since MPA implementation

roc5.b: returns the area under an reciever operating characteristic curve for biomass at year 5 since MPA implementation

roc10.b: returns the area under an reciever operating characteristic curve for biomass at year 10 since MPA implementation

roc20.b: returns the area under an reciever operating characteristic curve for biomass at year 20 since MPA implementation

Examples

openpop_ratio(tf=50, M=0.2,Fi=0.14,Lfish=25,Linf=37.8,k=0.13,a0=-0.7,maxage=25,pW=9.37e-06,qW=3.172,R=500,
 sig_r=0.5, MPAtime=1,simulations=100)

katherinekaplan/MPApopulationmodels documentation built on May 22, 2019, 8:51 p.m.