Home range use and movement patterns of non-native feral goats in a tropical island montane dry landscape

PLoS One. 2015 Mar 25;10(3):e0119231. doi: 10.1371/journal.pone.0119231. eCollection 2015.

Abstract

Advances in wildlife telemetry and remote sensing technology facilitate studies of broad-scale movements of ungulates in relation to phenological shifts in vegetation. In tropical island dry landscapes, home range use and movements of non-native feral goats (Capra hircus) are largely unknown, yet this information is important to help guide the conservation and restoration of some of the world's most critically endangered ecosystems. We hypothesized that feral goats would respond to resource pulses in vegetation by traveling to areas of recent green-up. To address this hypothesis, we fitted six male and seven female feral goats with Global Positioning System (GPS) collars equipped with an Argos satellite upload link to examine goat movements in relation to the plant phenology using the Normalized Difference Vegetation Index (NDVI). Movement patterns of 50% of males and 40% of females suggested conditional movement between non-overlapping home ranges throughout the year. A shift in NDVI values corresponded with movement between primary and secondary ranges of goats that exhibited long-distance movement, suggesting that vegetation phenology as captured by NDVI is a good indicator of the habitat and movement patterns of feral goats in tropical island dry landscapes. In the context of conservation and restoration of tropical island landscapes, the results of our study identify how non-native feral goats use resources across a broad landscape to sustain their populations and facilitate invasion of native plant communities.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Animal Distribution*
  • Animals
  • Ecosystem*
  • Female
  • Goats*
  • Hawaii
  • Islands
  • Male
  • Movement*
  • Remote Sensing Technology

Grants and funding

Funding was provided by the National Science Foundation Graduate Research Fellowship under Grant #2010094953 to MWC; USDA Forest Service, Pacific Southwest Research Station, Institute of Pacific Islands Forestry Research Joint Venture 08-JV-11272177-074 to CML; Strategic Environmental Research and Development Program RC-1645 to SC; W. T. Yoshimoto Foundation Endowed Fellowship in Animal Wildlife Conservation Biology to MWC. Support for SH was provided by the Invasive Species Program of USGS. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.