Recovery of Native Plant Communities and Ecological Processes Following Removal of Non-native, Invasive Ungulates from Pacific Island Forests
Abstract
Nonnative ungulates exert a large negative effect on native biodiversity and thestructure and function of terrestrial ecosystems throughout the Pacific Island region. In Hawaii,removal of ungulates is broadly recognized as a critical first step in conserving native ecosystemsand species, particularly threatened, endangered, and at-risk species (TER-S). To this end, land managers commonly fence and remove nonnative ungulates where conservation of native biodiversity is a priority. However, these actions are labor and cost intensive, and the long-term outcomes are not well quantified. Surprisingly little information exists on the magnitude and time frame of native plant recovery across different ecosystem types, the potential for nonnative plant invasions, or the response of critical, underlying ecological processes to nonnative ungulate removal. This study quantified the impacts of nonnative ungulate removal on the biodiversity, structure, and function of two major ecosystem types tropical wet forest (TWF) and tropical dry forest (TDF) found on DoD installations throughout the Pacific Island region. Specifically, we examined pathways and mechanisms through which ungulate removal impacts native and nonnative plant dynamics in four distinct ecosystem/plant community types. We also measured how ungulate removal affects key underlying ecological processes in three of these ecosystem types, focusing on ecosystem carbon (C) storage and flux, and soil nitrogen (N) cycling and availability. We then tested if manipulation of soil nutrients can be used as a management tool to favor native plants over nonnative, invasive plants in both greenhouse and field experiments. Finally, we initiated the development of a Decision Support Tool (DST) to assist land managers at the DoD Phakuloa Training Area to spatially prioritize land management decisions associated with TER-S throughout a large and complex landscape.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 2018
- Accession Number
- AD1073437
Entities
People
- Christian P. Giardina
- Creighton Litton
- Jed P. Sparks
- Rebecca J. Cole
Organizations
- University of Hawaiʻi at Mānoa