Endangered Butterflies as a Model System for Managing Source-Sink Dynamics on Department of Defense Lands
RC-2119
Objective
Department of Defense lands provide the best available habitat for numerous threatened, endangered, and at-risk species (TER-S), and many of these species are currently managed on military lands by controlled disturbances (e.g., fires) or by de novo restoration of habitat. However, these management strategies run the risk of converting sources (where births exceed deaths) into sinks (where deaths exceed births) or of creating ecological traps--low-quality but attractive restored habitat that draws animals from nearby sources, threatening metapopulation viability. Importantly, this work will focus on temporal change in habitat quality following management or restoration that may lead local habitat patches to cycle from sink to source status and back.
Through a combination of field studies and state-of-the-art quantitative models, the objective is to use three species of endangered butterflies as a model system to rigorously investigate the source-sink dynamics of species being managed on military lands.
Technical Approach
Butterflies have numerous advantages as models for source-sink dynamics, including rapid generation times and relatively limited dispersal, but they are subject to the same processes that determine source-sink dynamics of longer-lived, more vagile taxa. For two of the focal species, researchers will use previous restorations and ongoing management to study temporal source-sink dynamics, but for the third they will initiate new habitat restoration, enabling management effects to be examined in a controlled experiment. For all three species, researchers will measure both demography and movement behaviors at all phases of the disturbance cycle that follows management or restoration. These data will be used to parameterize detailed, spatially explicit, individual-based simulation models (SEIBMs) linked to real landscapes with dynamic changes in habitat quality due to management. The SEIBMs will be used to compare different management scenarios being considered at Camp Adair and/or Fern Ridge, Oregon; Fort Bragg, North Carolina; and Fort Lewis, Washington. The models will be validated by challenging them to reproduce the observed dynamics of butterfly populations on the managed landscapes.
Benefits
With the validated models, researchers will collaborate directly with managers of the focal species to assess which of multiple management strategies have the greatest chance of improving metapopulation viability at the lowest cost, taking potential source-sink dynamics into account. One key question is where restored habitat should be located relative to remnant populations to avoid creating ecological traps. The SEIBMs also will be used to ask: How much information is actually needed to accurately assess the source-sink status of managed and restored habitat? This question will be addressed by successively "deleting" more and more information about demography, movement behavior, and the landscape to determine the breaking point at which the ability to capture source-sink dynamics degrades completely. (Anticipated Project Completion - 2016)
Symposium & Workshop
FY 2013 New Start Project Selections
Points of Contact
Principal Investigator
Dr. Elizabeth Crone
President and Fellows of Harvard College
Phone: 978-724-3302
Fax: 978-724-3595
Program Manager
Resource Conservation and Climate Change
SERDP and ESTCP
Document Types
- Fact Sheet - Brief project summary with links to related documents and points of contact.
- Final Report - Comprehensive report for every completed SERDP and ESTCP project that contains all technical results.
- Cost & Performance Report - Overview of ESTCP demonstration activities, results, and conclusions, standardized to facilitate implementation decisions.
- Technical Report - Additional interim reports, laboratory reports, demonstration reports, and technology survey reports.
- Guidance - Instructional information on technical topics such as protocols and user’s guides.
- Workshop Report - Summary of workshop discussion and findings.
- Multimedia - On demand videos, animations, and webcasts highlighting featured initiatives or technologies.
- Model/Software - Computer programs and applications available for download.
- Database - Digitally organized collection of data available to search and access.