Overview

Although much work has been done on the question of how to manage land for the persistence of rare species, less has been done on where specifically to apply such management techniques. In metapopulations, which rely on propagule dispersal between patches for long-term stability, the spatial distribution of managed patches is extremely important. In addition, it is not always obvious where the appropriate habitat to manage is located, since in a metapopulation, only a fraction of the patches that influence the metapopulation dynamics are occupied at any given time. The identification and conservation of unoccupied habitat is therefore an important component of any plan to conserve a dispersal-dependent species.

I studied a set of populations of northern blazing star (Liatris scariosa var. novae-angliae) on Block Island, RI, which exhibit some of the properties of a metapopulation. I developed a novel method using Geographic Information Systems (GIS) to identify and prioritize habitat patches for conservation action, based on habitat suitability and the spatial relationship of each patch to the metapopulation. I found that, although the availability of suitable habitat has decreased drastically since the mid-20th century, The Nature Conservancy and other conservation organizations have protected a large proportion (roughly 50%) of the remaining high priority habitat. The prioritization of individual parcels of land will aid such organizations in the future to manage their land for this rare species, as well as to acquire new land for its protection. Furthermore, the method I developed is broadly applicable to other rare dispersal dependent species, and works with minimal data that is often freely available. Finally, the data generated for this project can be used in other established methods for the analysis of metapopulation health, as well as for other conservation projects on Block Island.

This work has been featured in the ESRI Map Book, Volume 19.