Objective

Many threatened species on Department of Defense lands also occur on lands managed by other jurisdictions (national forests, state lands, preserves managed by conservation organizations, etc.), yet each jurisdiction typically manages for those species independently, precluding the benefits of coordinated management. The main objective of this project was to provide tools to improve cross-jurisdictional management of three threatened species in the southeastern U.S., red-cockaded woodpecker (RCW), the St. Francis satyr butterfly (SFS), and Venus flytrap (VFT).

Technical Approach

Keys to understanding how best to manage across jurisdictions are to: 1) quantify how population asynchrony (which decreases metapopulation extinction risk) increases with distance between populations; 2) assess how climate change will alter both trends in each population and synchrony between them; 3) understand what spatial scale of management can avoid creating population synchrony; and 4) incorporate dispersal that can buffer a collection of jurisdictions against population decline in any one of them. This project accomplished these tasks for the focal species through a combination of: 1) analysis of long-term demographic data for all three species; 2) quantification of dispersal for RCW and SFS; 3) measurement of the effects of restoration on cover of the foodplants of SFS (sedges); and 4) construction and analysis of population models, including spatially explicit individual-based models (SEIBM) to guide acquisition of land parcels to enhance among-jurisdiction dispersal of RCW, and to guide habitat restoration for SFS and fire management for VFT while maintaining beneficial asynchrony.

Results

Demographic synchrony generally declines with distance between RCW populations, supporting the benefit of preserving multiple, disparate populations. 2) Cover of sedges increases and then decreases with time since restoration (so re-restoration is essential for SFS). 3) Dispersal of RCW and (especially) SFS is limited and must be considered when acquiring land parcels for RCW dispersal corridors or designing restoration schemes for SFS. 4) VFT populations do best at intermediate fire return intervals and may benefit from a future, warmer climate. 5) New SEIBM for RCW and SFS, and a climate- and fire-driven patch model for VFT, are now fully operational and available to managers in multiple jurisdictions.   

Benefits

The aim of this project was to provide quantitative tools that will aid managers in protecting populations of the three focal species both within jurisdictions (e.g., at Ft. Bragg, the only home of SFS) and between jurisdictions. Because these models are spatially explicit and include climate effects, they can help to make very specific recommendations about management (e.g., where to restore SFS habitat; see figure at right) and to assess whether management needs to be modified in the face of changes in climate, in habitat quality, and in human land use. 

How the SFS SEIBM can address management questions. Blue = high quality sedge meadows where SFS breeds; light green: riparian woodland (low sedge); dark green: uplands unsuitable for sedges; yellow: newly restored areas.