ypr (version 0.4.0)

ypr_population: Population Parameters

Description

Generates an object of class ypr_population.

Usage

ypr_population(
  tmax = 20L,
  k = 0.15,
  Linf = 100,
  t0 = 0,
  k2 = 0.15,
  Linf2 = 100,
  L2 = 1000,
  Wb = 3,
  Ls = 50,
  Sp = 100,
  es = 1,
  Sm = 0,
  fb = 1,
  tR = 1L,
  BH = 1L,
  Rk = 3,
  n = 0.2,
  nL = 0.2,
  Ln = 1000,
  Lv = 50,
  Vp = 100,
  Llo = 0,
  Lup = 1000,
  Nc = 0,
  pi = 0.2,
  rho = 0,
  Hm = 0,
  Rmax = 1,
  Wa = 0.01,
  fa = 1,
  q = 0.1
)

Arguments

tmax

The maximum age (yr).

k

The VB growth coefficient (yr-1).

Linf

The VB mean maximum length (cm).

t0

The (theoretical) age at zero length (yr).

k2

The VB growth coefficient after length L2 (yr-1).

Linf2

The VB mean maximum length after length L2 (cm).

L2

The length (or age if negative) at which growth switches from the first to second phase (cm or yr).

Wb

The weight (as a function of length) scaling exponent.

Ls

The length (or age if negative) at which 50 % mature (cm or yr).

Sp

The maturity (as a function of length) power.

es

The annual probability of a mature fish spawning.

Sm

The spawning mortality probability.

fb

The fecundity (as a function of weight) scaling exponent.

tR

The age from which survival is density-independent (yr).

BH

Recruitment follows a Beverton-Holt (1) or Ricker (0) relationship.

Rk

The lifetime spawners per spawner at low density.

n

The annual interval natural mortality rate from age tR.

nL

The annual interval natural mortality rate from length Ln.

Ln

The length (or age if negative) at which the natural mortality rate switches from n to nL (cm or yr).

Lv

The length (or age if negative) at which 50 % vulnerable to harvest (cm or yr).

Vp

The vulnerability to harvest (as a function of length) power.

Llo

The lower harvest slot length (cm).

Lup

The upper harvest slot length (cm).

Nc

The slot limits non-compliance probability.

pi

The annual capture probability.

rho

The release probability.

Hm

The hooking mortality probability.

Rmax

The number of recruits at the carrying capacity (ind).

Wa

The (extrapolated) weight of a 1 cm individual (g).

fa

The (theoretical) fecundity of a 1 g female (eggs).

q

The catchability (annual probability of capture) for a unit of effort.

Value

An object of class ypr_population.

See Also

ypr_population_update(), ypr_tabulate_schedule(), ypr_yield() and ypr_optimize().

Examples

# NOT RUN {
ypr_population(k = 0.1, Linf = 90)
# }