SPASAM.MSE

Build: v1.1.2 • 2026-03-14
SPASAM-MSE (Spatial Processes and Stock Assessment Methods - Management Strategy Evaluation) is a spatially explicit, closed-loop MSE platform built on WHAM (Woods Hole Assessment Model), a state-space, age-structured stock assessment framework used in NOAA/NEFSC applications.
Multi-stock • Multi-region
Connectivity • Mixing • Natal homing • Metapopulation
Configurable OM spatial structure
Alternative EM spatial structure
State-space features
Flexible data-generation pipeline
Flexible projection pipeline
Flexible harvest control rules
Implementation uncertainty
Parallel simulations
Automated reporting
SPASAM.MSE logo

Quick install

Development version from GitHub:

remotes::install_github("lichengxue/SPASAM.MSE")

Package name: SPASAM.MSE

Main developer: Chengxue Li <chengxue.li@stonybrook.edu>
Core SPASAM members:
Jonathan Deroba — NOAA Federal (NEFSC) <jonathan.deroba@noaa.gov>
Daniel Goethel — NOAA Federal (AFSC) <daniel.goethel@noaa.gov>
Aaron Berger — NOAA Federal (NWFSC) <aaron.berger@noaa.gov>
Amy Schueller — NOAA Federal (SEFSC) <amy.schueller@noaa.gov>
Brian Langseth — NOAA Federal (NWFSC) <brian.langseth@noaa.gov>
Dana Hanselman — NOAA Federal (AFSC) <dana.hanselman@noaa.gov>
Emily Liljestrand — NOAA Federal (NEFSC) <emily.liljestrand@noaa.gov>
Timothy Miller — NOAA Federal (NEFSC) <timothy.j.miller@noaa.gov>

What SPASAM-MSE does

SPASAM.MSE provides a flexible spatial operating model and an end-to-end workflow to test management procedures under realistic spatial structure and movement. It is designed for research and method development where spatial processes can drive estimation bias and management risk.

  • Simulate spatial population structure, mixing, and connectivity (including natal homing and metapopulation dynamics).
  • Generate fishery-dependent and fishery-independent data under alternative spatial sampling designs.
  • Fit alternative estimation models with different spatial structures and compare against operating-model truth across scenarios and replicates.
  • Evaluate trade-offs and risk across regions and stocks under closed-loop feedback.

Core capabilities

  • Closed-loop MSE: OM -> data -> EM -> projections -> HCR -> implementation uncertainty -> feedback.
  • Spatial control: spatial heterogeneity in population biology and fishing dynamics across regions, with explicit connectivity linking regions.
  • Flexible EM spatial structure: evaluate estimation models with alternative spatial assumptions (e.g., spatial aggregation, region/fleet structure, and movement simplifications).
  • Movement scenarios: bidirectional vs unidirectional connectivity, natal homing and metapopulation structure, movement trends, and optional environmental covariate effects on movement.
  • State-space structure: WHAM-based design that treats key biological and fishery processes as random effects (time- and/or age-varying) in both OM and EM.
  • Performance evaluation: bias/precision, status metrics, risk of overfishing/overfished, and spatial trade-offs in catch, SSB, and F.
  • Parallel simulations: scalable pipelines for multi-scenario experiments.
  • Automated reporting: PNG/HTML/PDF outputs for large simulation studies.