gillnet: gillnet selection

In marchtaylor/fishdynr: Fisheries science related population dynamics models

Description

gillnet describes gillnet selection following Millar and Holst (1997). Possible selectivity distributions include normal (fixed width) and lognormal. [Note: others will be added]

Usage

gillnet(Lt, mesh_size, mesh_size1, select_dist, select_p1, select_p2)

Arguments

Lt	body size
mesh_size	mesh size
mesh_size1	smallest reference mesh size
select_dist	selectivity type ("normal_fixed", "lognormal")
select_p1	selectivity function parameter 1 (see Millar and Holst 1997)
select_p2	selectivity function parameter 2 (see Millar and Holst 1997)

References

Millar, R. B., & Holst, R. (1997). Estimation of gillnet and hook selectivity using log-linear models. ICES Journal of Marine Science: Journal du Conseil, 54(3), 471-477.

Examples

data(tilapia)
tilapia$selectFun="gillnet"
mesh_sizes <- c(60, 80, 100, 120)
for(i in seq(mesh_sizes)){
  tilapia$mesh_size <- mesh_sizes[i]
  res <- cohortSim(tilapia, t_incr=0.01)
  if(i == 1) plot(pcap ~ Lt, res, t="n")
  lines(pcap ~ Lt, res, col=i)
}
legend("topleft", legend=mesh_sizes, 
  col=seq(mesh_sizes), lty=1, 
  title="mesh size [mm]", bty="n"
)

marchtaylor/fishdynr documentation built on May 21, 2019, 11:27 a.m.