Western Arctic caribou herd winter lichen, snow depth, and mortality

This repository contains data and code to generate results and figures from 'Winter survival shaped by forage abundance and snow depth for a long-distance migratory ungulate.' The dataset includes winter lichen cover, snow depth, and mortality data for adult female caribou from the Western Arctic Herd in northwestern Alaska. Each row represents unique locations from 372 caribou collected between 2009 and 2024, including information on snow depth, lichen cover, and mortality. Environmental data were derived from GPS collar locations; however, the locations themselves have been excluded due to restrictions on sharing data from harvested wildlife in Alaska.
, , , # Western Arctic caribou herd winter lichen, snow depth, and mortality

[https://doi.org/10.5061/dryad.qbzkh18tz](https://doi.org/10.5061/dryad.qbzkh18tz)

## Description of the data and file structure

The dataset is a single comma-separated table, where each row corresponds to a unique caribou ID and time. Movement data from adult female caribou (>2 years old) were collected using GPS telemetry collars (Telonics TGW-4680), following State of Alaska IACUC-approved protocols. Collars recorded locations every 2, 4, or 8 hours. Mortality events were identified when collars stopped moving but continued transmitting, creating clusters of positions at the same location. Mortality sites were visited when possible to recover collars and locate remains.

The dataset was analyzed to assess overwinter survival, including mortality during winter, maximum number of winter days, average snow depth, and mean lichen cover.

### Files and variables

#### File: wah_lichen_snow_mort.csv

| **Field name**...,