Software

Our lab is committed to open science. Whenever we publish a paper, we archive the associated data (when possible) and computer code used for all analyses and data visualizations in the Data Repository of the University of Minnesota.

In addition, we have contributed to the development of the following R packages to help ecologists implement the statistical methods we develop.

Featured Packages

Picture of step-length and turn angle distributions by land type

amt: Animal Movement Tools

The amt package provides functions to manage and analyze animal movement data. It focuses on:

Preparing data for analysis (e.g., thinning, resampling).
Fitting Step-Selection Functions (SSFs) and integrated step-selection functions (iSSFs).
Estimating home ranges (KDE, MCP, HRT) and home-range overlap.
Simulating movement paths from fitted models.

This is Johannes Signer’s brainchild! He is the primary developer, and he has a few helpers (e.g., Brian Smith). My role is largely advisory, and I teach several workshops (often with Johannes), demonstraing the package.

Observations of moose in Minnesota with a circular field of view used to measure the degree of visual obstruction. Photos by Mike Schrage, Fond du Lac Resource Management Division.

SightabilityModel

A key problem when surveying wildlife populations is that not all animals in a group are seen because sightability is < 1. Sightablity models leverage auxiliary study data (e.g. using radio collared individuals) to estimate detection probabilities using logistic regression, which can then be used to correct the observed counts in the current study. The SightabilityModel package uses this approch to estimate density, abundance or ratios (e.g. bulls to cows).

Other Tools

To come!