leslie: Leslie Matrix Population Model

In laurieKell/FLCandy: Candidate methods for FLR

Leslie Matrix Population Model

Description

Creates a Leslie Matrix from population parameters to model age-structured population dynamics at equilibrium. Calculates survival rates and fecundity to estimate population growth rate (r).

Arguments

object	An object of class FLBRP, numeric, FLQuant, FLPar, FLBiol, or FLStock
fec	Fecundity vector (optional)
f	Fishing mortality rate (default: crash F from reference points)
numbers	Logical; if TRUE returns numbers, if FALSE returns biomass (default: TRUE)

Details

The Leslie matrix (L) is constructed as:

• First row contains fecundity values

• Sub-diagonal contains survival probabilities

• Plus group handled in last row

Reference points derived as:

• Fmsy = r/2 (general) or 0.87M (teleosts) or 0.41M (sharks)

• Flim = 1.5Fmsy

• Fcrash = 2Fmsy

Value

A matrix (for numeric inputs) or array (for FLR objects) containing the Leslie matrix

See Also

lhRef lhPar lhEql

Examples

## Not run: 
# Simple numeric example
survivors <- cumprod(rep(0.5, 10))
fec <- c(0, rep(1, 9))
L <- leslie(survivors, fec)

# FLR example
eql <- lhEql(lhPar(FLPar(linf=100)))
L <- leslie(eql)

## End(Not run)

laurieKell/FLCandy documentation built on April 17, 2025, 5:23 p.m.