Accounting for movement in spatial surplus production models: A case study of redfish on the Eastern Grand Banks of Newfoundland

Spatial surplus production models (SSPMs) are a key alternative to spatial population dynamics models when reliable spatial aging data is unavailable. However, fish movements present computational challenges for SSPMs and can be confounded with process errors, hindering the identification of SSPM parameters. We propose leveraging a Gaussian Markov Random Field (GMRF) with a Matérn covariance structure to account for spatiotemporal variation in dynamics and population production, thereby circumventing the computational and confounding issues. Through simulation studies, wherein data is generated explicitly considering movements, our novel random field model outperforms the alternative methods in estimating fish spatial abundance, as evaluated using statistical metrics including Akaike information criterion, Bayesian information criteria, and correlation between simulated and estimated populations. We also applied our method to reveal the spatial distribution of redfish in NAFO 3LN divisi..., , # Accounting for Movement in Spatial Surplus Production Models: A Case Study on 3LN Redfish

Dataset DOI: [10.5061/dryad.rxwdbrvnn](10.5061/dryad.rxwdbrvnn)

## Description of the data and file structure

The final_submitted_codes.zip file contains two folders: simulations and redfish.

1\. simulations

This folder includes the TMB codes, R codes and data (i.e., redfish_results.RData) used for the simulation studies presented in the paper:

Accounting for Movement in Spatial Surplus Production Models: A Case Study of Redfish on the Eastern Grand Banks of Newfoundland by Hoang Nguyen, Jin Gao, Noel G. Cadigan, Yanjun Wang, Fan Zhang, Nan Zheng.

The CSV files are containers to store simulation results.

2\. redfish

This folder contains the TMB code, R code and data used for the case studies in the paper. The data files include the .RData files and a landings.txt file.

In both folders, the survey data are simulated due to restrictions from the Fisheries and Oceans Canada (DFO) on sharin...,