Integrating Field and GIS-based Surveys to Map the Distribution and Characterize the Ecological Habitat for Conservation Management of Georgia Plume, a Rare Endemic

Abstract

Accurate mapping, inventory assessment, and habitat descriptions are critically important for the development of plant conservation strategies of rare plants. Georgia plume, Elliottia racemosa (Ericaceae), is a rare threatened plant endemic only to the state of Georgia. In this study, census and distribution data were collected and the ecological habitat characterized for all known populations of georgia plume using geographic information system/global positioning system (GIS/GPS)-based methods. Causes for population losses and decline were assessed by evaluating both extant populations and historically reported but currently inactive sites. Landowner permission was obtained to visit 56% (32 of 57) of all known recorded populations. Over 40% of visited locations no longer contained georgia plume; 58% of inactive sites were associated with anthropogenic disturbances including farming and timber. Populations not visited by ground were evaluated using aerial photographs: of 29 putative populations, 66% were judged highly unlikely to contain georgia plume based on current land use. Census data verified that many populations have few individuals: 75% contained less than 45 individuals; over one-third contained 12 or fewer individuals. Over 80% of extant populations had an area of less than 0.3 ha. Field and aerial assessments of recent and historically noted populations confirm that georgia plume has disappeared from many previously reported locations and that fewer than two dozen populations may remain.