n_to_stock: Calculate the number of fish to stock based on desired...

In optistock: Determine Optimum Stocking Times Used in Fishery Enhancements

Calculate the number of fish to stock based on desired recruit number and given mortality curve

Description

This function is essentially the inverse of recruits_at_time. Given the number of fish desired at a certain time and the mortality function and parameters this function will calculate how many fish should be stocked into a system.

Usage

n_to_stock(
  time_at_stocking,
  time_at_rec,
  n_recruits_desired,
  mort_fun = exp_mort,
  mort_fun_args
)

Arguments

time_at_stocking	The time that fish are stocked (i.e. synonymous with the amount of time that fish are raised in a hatchery)
time_at_rec	The time at which a fish enters the fishery (i.e. the amount of time it takes a fish to grow to a desired length). Use inv_vb to calculate this.
n_recruits_desired	The number of recruits desired at time_at_rec
mort_fun	The mortality function, see ?mort_funs
mort_fun_args	List. Named arguments to be passed to mort_fun

Value

The number of fish to be stocked at time_at_stocking to get the desired number of fish at time_at_rec based on the mortality function and associated parameters

Examples

# how many fish to stock on day 100 if you want 10000 fish on day 1000
n_to_stock(10000, 100, 1000,
           mort_fun = exp_mort,
           mort_fun_args = list(m_init = (1 / 365),
                                m_inf = (0.2/365),
                                alpha = 0.005))

optistock documentation built on Aug. 24, 2023, 5:06 p.m.