Abstract Detail



Bryology and Lichenology

Charton, Katherine T. [1], Smith, Stacy [2], Menges, Eric [1].

Fighting fire: Trends in Cladonia perforata survival, cover, extent, and microhabitat preferences in a pyrogenic landscape.

The federally endangered Florida perforate reindeer lichen, Cladonia perforata, occurs on xeric and pyrogenic ridges throughout Florida, but most of the known populations occur in Florida rosemary scrub habitat along the Lake Wales Ridge. Because little is known about this lichen’s ecology, life history, and population dynamics, land managers have not been offered operational suggestions for its continued protection. We followed 13 known C. perforata subpopulations at Archbold Biological Station and Royce Ranch Wildlife and Environmental Area from 2011 to 2019 using a multi-spatial scale monitoring protocol (fine-scale cover, occupancy, and large-scale extent, along with microhabitat variables), with goals of detecting changes through time and in relation to fire regimes. To date, we have completed 3-year resurveys at 169 cover quadrats and 579 occupancy plots. We have also remapped subpopulation boundaries after 6 years at seven sites to monitor larger-scale changes in extent and search for recolonization every 6 years at five locally extinct sites. After the 3-year resurveys, overall percent C. perforata cover decreased slightly (2.83% to 2.34%), most notably so at the one subpopulation affected by prescribed fire between surveys (4.02% to 0.63%). Plot occupancy also decreased across subpopulations (42.5% to 37.8%), again markedly at the burned subpopulation (56.0% to 26.0%). We found no significant interactions between cover or occupancy and microhabitat variables, although trends suggested that C. perforata may have a preference for bare sand substrate. Aerial extents of subpopulation boundaries over 6 years varied but generally increased, with the exception of the longest unburned subpopulation and the subpopulation burned between survey dates, both of which have dramatically decreased. Recolonization was observed in one previously locally extinct subpopulation 8 years post-fire. We recognize that C. perforata remains extremely endangered due to its limited range, small patch sizes, slow growth rate, and especially its negative response to fire. Our results support the commonly held assumption that C. perforata is killed by fire, but some fragments may persist and recolonize. We recommend facilitating patchy fires and reintroductions where necessary to help this species recover. Continued scientific studies are necessary to further our understanding of this species’ ecology, life history, and population dynamics, and to formulate more nuanced conservation recommendations for land managers.


Related Links:
Species Account: Cladonia perforata (Cladoniaceae) Evans


1 - Archbold Biological Station, Plant Ecology Program, 123 Main Drive, Venus, Florida, 33960, United States
2 - University of Florida, Agronomy Department, Gainesville, FL, 32611, United States

Keywords:
Lichens
population ecology
Prescribed fire
demography
Endangered species.

Presentation Type: Oral Paper
Number: 0013
Abstract ID:372
Candidate for Awards:None


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