project_pop: Project population

In danStich/anadrofish: Anadromous Fish Population Responses to Habitat Changes

Project population

Description

Function used to project population forward one time step using vector multiplication.

Usage

project_pop(x, age0, nM, fM, max_age, species = c("AMS", "ALE", "BBH"))

Arguments

x	A numeric vector containing age-specific abundance at end of year t.
age0	A numeric vector of length one containing number of new recruits at end of year t.
nM	Numeric vector of instantaneous natural mortality.
fM	Numeric vector of instantaneous fishing mortality.
max_age	Numeric indicating maximum age of spawning fish.
species	Species for which population dynamics will be simulated. Choices include American shad ("AMS"), alewife ("ALE"), and blueback herring ("BBH").

Value

A numeric vector of age-structured abundance in time t + 1.

Examples

# Example usage
## Not run: 
  
 # Simulate a population
 n_init = 1e5  
 max_age = 13
 nM = .505
 fM = 0
 pop = make_pop(max_age=max_age, nM=nM, fM=fM, n_init=n_init)
 
 # Project one time-step without reproduction
 new_pop = project_pop(x=pop, age0=1e5, nM=.505, fM=0, max_age)
 
 # Difference should be about zero 
 # because age0 - n_init
 new_pop - pop
  

## End(Not run)

danStich/anadrofish documentation built on Jan. 17, 2025, 9:46 a.m.