M_calc: Compute constant natural mortality estimates from life...

In nikolaifish/bamExtras: Functions and Data in Support of Stock Assessments with the Beaufort Assessment Model (BAM)

Compute constant natural mortality estimates from life history parameters

Description

Compute constant natural mortality estimates from life history parameters

Usage

M_calc(type = "all", tmax, Linf, K)

Arguments

type	Type of M calculation to use. If type="all" the function tries all calculations and returns a vector of all results. NA values indicate that a particular calculation couldn't be computed, probably because a necessary life history parameter was not provided. Possible values include four calculations specified in Hoenig (1983; Table 1; "Hng_Mollusks", "Hng_Fish", "Hng_Cetaceans", "Hng_All") and six calculations from Then et al. (2014; Table 3; "Thn_1partmax", "Thn_Hnglm", "Thn_Hngnls", "Thn_1parK", "Thn_2parK", "Thn_Plynls").
Linf	length infinity in cm (von Bertalanffy growth equation parameter)
K	growth coefficient (von Bertalanffy growth equation parameter)
t0	age (time) at length zero (von Bertalanffy growth equation parameter)

Author(s)

Nikolai Klibansky

References

Hoenig, J. M. 1983. Empirical use of longevity data to estimate mortality-rates. Fishery Bulletin 81:898-903.

Then, A. Y., J. M. Hoenig, N. G. Hall, and D. A. Hewitt. 2014. Evaluating the predictive performance of empirical estimators of natural mortality rate using information on over 200 fish species. ICES Journal of Marine Science.

Examples

## Not run: 
# Return all possible estimates based on tmax
M_calc(tmax=11)
# Return all possible estimates based on tmax or K
M_calc(tmax=11,K=0.173)
# Return all possible estimates based on tmax, K, or Linf (in centimeters)
M_calc(tmax=11,Linf=50.2,K=0.173)
# Return just the Hoenig_nls estimate published in Then et al. (2014) based on tmax
M_calc(type="Thn_Hngnls",tmax=11)

## End(Not run)

nikolaifish/bamExtras documentation built on July 21, 2023, 8:26 a.m.