get_rec_fun {LeMaRns}

Collate the stock recruitment functions

Description

Collates the stock recruitment functions for all of the species in the model.

Usage

get_rec_fun(rec_fun = "hockey-stick")

Arguments

rec_fun

A character vector representing the stock recruitment function to be applied to each species. The default is "hockey-stick", but rec_fun can also take "Ricker", "Beverton-Holt", "constant", or "linear" for each species.

Details

For "Beverton-Holt", the stock recruitment function is defined as a*SSB/(1+b*SSB); for "Ricker" it is defined as a*SSB*exp(-b*SSB); for "hockey-stick" it is defined as min(a*SSB, b); for "constant" it is defined as a, and for "linear" it is defined as a*SSB. In all cases, SSB is the Spawning Stock Biomass in 1000s of tonnes and a and b are parameters of the specific stock recruitment functions.

Value

A list object of length rec_fun where each element includes the stock recruitment function for a given species. If an invalid recruitment function is selected, NULL is returned and a warning message is shown.

References

Barrowman, N.J., Myers, R.A. (2000). Still more spawner-recruit curves: the hockey stick and its generalisations. Canadian Journal of Fisheries and Aquatic Science, 57:665–676.

Beverton, R.J.H., Holt, S.J. (1957). On the Dynamics of Exploited Fish Populations, volume 19 of Fisheries Investigations (Series 2). United Kingdom Ministry of Agriculture and Fisheries.

Hall, S. J., Collie, J. S., Duplisea, D. E., Jennings, S., Bravington, M., & Link, J. (2006). A length-based multispecies model for evaluating community responses to fishing. Canadian Journal of Fisheries and Aquatic Sciences, 63(6):1344-1359.

Ogle, D.H. (2016). Introductory Fisheries Analyses with R. CRC Press.

Ricker, W.E. (1954). Stock and recruitment. Journal of the Fisheries Research Board of Canada, 11:559-623.

Thorpe, R.B., Le Quesne, W.J.F., Luxford, F., Collie, J.S., Jennings, S. (2015). Evaluation and management implications of uncertainty in a multispecies size-structured model of population and community responses to fishing. Methods in Ecology and Evolution, 6:49-58.

See Also

calc_recruits, make_rec_fun, rec_BH, rec_Ricker, rec_hockey, rec_const, rec_linear and calc_SSB

Examples

nfish <- nrow(NS_par)
stored_rec_funs <- get_rec_fun(rep("hockey-stick", nfish))