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spdgt.sdm

Structured decision making for wildlife harvest management.

spdgt.sdm evaluates harvest management alternatives by scoring how well each option satisfies different stakeholder groups. It turns the subjective question “which regulation is best?” into a transparent, defensible comparison.

Installation 

install.packages("spdgt.sdm",
  repos = c("https://nexus.spdgt.com/repository/r-public",
            "https://cloud.r-project.org"))

Quick start 

library(spdgt.sdm)

# Load species-specific defaults
objs <- sdm_read_objectives(species = "moose")
grps <- sdm_read_groups(species = "moose")

# Define management alternatives
alts <- list(
  sdm_alternative(
    name = "Status Quo",
    description = "Current regulations (20% harvest rate)",
    metrics = c(licenses = 5000, days_per_animal = 8.5,
                lambda = 0.987, sex_ratio = 0.45, harvest = 117)
  ),
  sdm_alternative(
    name = "Reduce Harvest",
    description = "Conservative approach (10% harvest rate)",
    metrics = c(licenses = 3000, days_per_animal = 12.0,
                lambda = 1.084, sex_ratio = 0.52, harvest = 77)
  )
)

# Build scenario and evaluate
scn <- sdm_scenario(
  name = "Moose Harvest Review",
  species = "Moose",
  objectives = objs,
  groups = grps,
  alternatives = alts
)

results <- sdm_evaluate_scenario(scn)
results$matrix

What you need

  • A SpeedGoat account (authentication is automatic)
  • Two or more management alternatives with metric values – from an IPM, harvest data, or your best estimates

You do not need an IPM. Manual estimates, harvest records, or expert judgment all work.

Learn more

Support

Email software@speedgoat.io for technical support or feature requests.