DOI: 10.5061/dryad.w6m905qtr
title: Identifying temporal dynamics in post-release survival of a restored large ungulate

description: Wildlife translocation is an important conservation tool for restoring
 species and reducing global biodiversity decline; however, this practice
 is challenging for wildlife, and translocated individuals must adjust to
 their release landscapes for restoration success. The period following
 release is a vulnerable time for wildlife and determining when animals
 acclimate following translocation improves long-term estimates of
 population dynamics and allows researchers to efficiently tailor
 translocation design and post-release management to each population’s
 needs. We evaluated demographic acclimation and investigated changes in
 post-release survival of a population of 106 elk (Cervus canadensis)
 translocated to Missouri, U.S.A., from 2011 to 2013 using generalized
 survival modeling. We defined the acclimation period as the duration of
 time prior to stabilization in mortality risk relative to time from
 release, and we evaluated acclimation duration from flexible plots of
 estimated mortality hazards across time. We simultaneously investigated
 factors contributing to post-release survival and compared survival rates
 and mortality sources observed during acclimation and post-acclimation
 periods. Elevated mortality risk for translocated elk spanned a 5-month
 acclimation period following release, with an additional one-year period
 reflecting reduced, but still elevated, mortality hazards. Baseline
 hazards during the initial 5-month acclimation period were approximately
 four times higher than the subsequent 4.4 years following release. Release
 cohort, but not age class or sex, was associated with post-release
 mortality risk, and mortality sources within the acclimation period tended
 to be undetermined with greater frequency relative to mortalities
 occurring after the acclimation period. Synthesis and applications. Our
 results highlight the utility of flexible modeling approaches to evaluate
 dynamic post-release responses of translocated populations. Translocated
 elk demonstrated a pronounced demographic acclimation period that spanned
 five months following release. Changes in mortality sources and the timing
 of stabilization in mortality hazards suggest that demographic acclimation
 in translocated elk was associated with adjustments in physiological
 stress and movement rates that stabilize over a similar post-release
 duration. Improving post-release monitoring and assessment of restored
 populations by evaluating temporal dynamics of manifold biological and
 ecological responses of translocated animals.
description: Data for survival analyses was collected through GPS- and
 VHF-collar based monitoring. Collars contained motion-sensitive mortality
 sensors programmed to activate after 4 h without movement, and collars
 transmitted mortality notifications remotely via satellite. If collars
 lost GPS functionality or remote notifications of mortality alerts, we
 performed bi-weekly VHF driving surveys across the extent of occupied elk
 range within the ERZ. When collars indicated mortality (either by remote
 notification or via VHF signal), we recovered them as soon as possible
 (typically within 24-hr but not beyond 72-hr) to assess day of death and
 examine carcasses for cause of mortality following established methods
 from contemporary neonatal ungulate survival studies