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

Value

Vector of density-dependent reproduction rates.

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().

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