BevertonHoltRDD {mizer}

Beverton Holt function to calculate density-dependent reproduction rate

Description

Takes the density-independent rates R_{di} of egg production (as calculated by getRDI()) and returns reduced, density-dependent reproduction rates R_{dd} given as

R_{dd} = R_{di} \frac{R_{max}}{R_{di} + R_{max}}

where R_{max} are the maximum possible reproduction rates that must be specified in a column in the species parameter dataframe. (All quantities in the above equation are species-specific but we dropped the species index for simplicity.)

Usage

BevertonHoltRDD(rdi, species_params, ...)

Arguments

rdi

Vector of density-independent reproduction rates R_{di} for all species.

species_params

A species parameter dataframe. Must contain a column R_max holding the maximum reproduction rate R_{max} for each species.

...

Unused

Details

This is only one example of a density-dependence. You can write your own function based on this example, returning different density-dependent reproduction rates. Three other examples provided are RickerRDD(), SheperdRDD(), noRDD() and constantRDD(). For more explanation see setReproduction().

Value

Vector of density-dependent reproduction rates.

See Also

Other functions calculating density-dependent reproduction rate: RickerRDD(), SheperdRDD(), constantEggRDI(), constantRDD(), noRDD()