Make spawning population

The purpose of this function is to create an age-structured spawning population from an existing age-structured population by applying region- and age-specific spawning probabilities.

Usage

make_spawners(pop, probs)

Arguments

pop

Age-structured spawner abundance.

probs

Vector of spawning probabilities. May be a single value or multiple. If multiple values are passed as a vector, the length of probs should correspond to the length of pop.

Value

A numeric vector of length = length(pop)

References

Atlantic States Marine Fisheries Commission

Examples

# Example usage
if (FALSE) { # \dontrun{
  
# Population vital rates
  max_age = 9
  nM = 0.38
  fM = 0.00
  n_init = 1e5
  
# Simulate a fish population at stable age distribution
  pop = make_pop(max_age = max_age,
                 nM = nM,
                 fM = fM,
                 n_init = n_init)
  
# Spawners ----
# Define probability of recruitment to spawn- probability of
# recruitment to the first spawning event
# by age class (Bailey and Zydlewski 2013)
### This is using probability of first spawn.
### clearly does not work here because it will always
### result in the oldest age classes having the most fish
  spawnRecruit <- c(0, 0, 0, 0.01, .33, .84, .97, .99, 1.00)  

# Get spawner numbers  
  spawners <- make_spawners(pop, probs = spawnRecruit)
  spawners
  
} # }