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Summarise offtake and stock Variation for a steady-state year

Source: R/core_model_demographic_herd.R
calc_summary_offtake.Rd

Calculates annual offtake quantities and rates, as well as stock variation and their combined values across 6 sex-age classes based on steady-state population projections. The steady state is defined as a constant sex–age cohort structure over time, with population size potentially growing or declining at a constant rate.

Usage

calc_summary_offtake(
  cohort_stock_start,
  cohort_stock_end_projected,
  cohort_stock_average,
  cohort_offtake_heads,
  simulation_duration
)

Arguments

cohort_stock_start

Numeric vector of length 6. Population size in each of the 6 sex–age cohorts at the start of the year (# heads). (cohorts= FJ, FS, FA, MJ, MS, MA)

cohort_stock_end_projected

Numeric vector of length 6. Population size in each of the 6 sex–age cohorts at the end of the year, projected using the steady-state growth rate (# heads). (cohorts= FJ, FS, FA, MJ, MS, MA)

cohort_stock_average

Numeric vector of length 6. Average population size in each of the 6 sex–age cohorts over the year (# heads). Estimated from cohort_stock_start and cohort_stock_end_projected (cohorts= FJ, FS, FA, MJ, MS, MA)

cohort_offtake_heads

Numeric vector of length 10. Total number of animals removed from the herd over the year, by 10 sex–age cohorts (heads/year) (cohorts= FB: Female Birth, FJ: Female Juvenile, FS: Female Sub-adult, FA: Female Adult, FC: Female Culling, MB: Male Birth, MJ: Male Juvenile, MS: Male Sub-adult, MA: Male Adult, MC: Male Culling)

simulation_duration

Numeric. Length of the assessment period (days)

Value

A named list with:

stock_variation_heads

Numeric vector of length 6. Change in population size between the start and end of the year for each sex–age cohort (# heads) (cohorts= FJ, FS, FA, MJ, MS, MA).

offtake_heads

Numeric vector of length 6. Total number of animals removed via offtake over the year, aggregated to 6 sex–age cohorts (heads/year) (cohorts= FJ, FS, FA, MJ, MS, MA)

offtake_heads_assessment

Numeric vector of length 6. Total number of animals removed via offtake over the assessment period, aggregated to 6 sex–age cohorts (heads/assessment period) (cohorts= FJ, FS, FA, MJ, MS, MA)

offtake_rate_to_stock_start

Numeric vector of length 6. Offtake rate relative to the starting population size in each sex–age cohort (fraction) (cohorts= FJ, FS, FA, MJ, MS, MA)

offtake_rate_to_stock_average

Numeric vector of length 6. Offtake rate relative to the average population size in each sex–age cohort (fraction) (cohorts= FJ, FS, FA, MJ, MS, MA)

offtake_stock_variation_heads

Numeric vector of length 6. Sum of offtake and stock variation for each sex–age cohort over the year (# heads) (cohorts= FJ, FS, FA, MJ, MS, MA)

offtake_stock_plus_variation_rate_to_stock_start

Numeric vector of length 6. Offtake plus stock-variation rate relative to starting population size (fraction) (cohorts= FJ, FS, FA, MJ, MS, MA)

offtake_stock_plus_variation_rate_to_stock_average

Numeric vector of length 6. Offtake plus stock-variation rate relative to average population size (fraction) (cohorts= FJ, FS, FA, MJ, MS, MA)

This function is part of the run_demographic_herd_module().

See also

run_demographic_herd_module()