Ecological Research

Research Supports Conservation

In addition to research relating to seeds and plant reintroductions, we also conduct ecological research that examines the relationships between native South Florida plants and their ecosystems, management, or reproduction.  Brief descriptions of some of these studies are given below.

 
Restoration of Jacquemontia reclinata in South Florida (1999-present)

Jacquemontia reclinata is a federally endangered vine endemic to the coastal strand and dune habitats of South Florida. Fairchild has worked with land managers and researchers to conduct a landscape scale multi-institutional and multidisciplinary project to recover Jacquemontia reclinata. Thanks to this effort we know where plants occur, how populations are doing, and what the species' habitat requirements are. Genetic studies revealed the structure and genetic diversity of existing populations (Thornton et al. 2008).  We identified the pollinators (Pinto-Torres and Koptur 2009). We unlocked the secrets of propagation, seed germination and long-term storage in the laboratory and the wild (Roncal et al. 2006; Pascarella et al. 2011).  We know that plants will grow best if they have mycorrhizal mutualists (Fisher and  Jayachandran 2002).  With numerous volunteers we have restored habitat, more than doubled the numbers of plants in the wild, and created new populations of Jacquemontia reclinata along the eastern coast of Florida ( Maschinski and Wright 2006.)   And we are still learning how to increase the species’ resilience to climate change (Maschinski et al. 2013).


Assessing hurricane impacts on populations and taking conservation steps for the endangered Keys tree cactus
Pilosocereus robinii (2006-present)

Pilosocereus robinii is an endangered cactus that grows in rockland hammocks in the Florida Keys. It has experienced a rapid population decline in recent years. Fairchild biologists have surveyed and mapped the populations of this plant and conducted research to explore the causes for the mortality that has occurred (Goodman et al. 2012b). To augment ex situ collections for conservation of the species and for future reintroductions, we have  collected cuttings and seeds.  Our seed germination studies show that the species is capable of long-term storage.  Recently we conducted an experimental reintroduction of the species to examine ecological conditions need to support self-sustaining populations.  If you would like to learn more about the Key tree cactus, click here to watch a short video about the species.


Effects of fire regime on diversity in pine rocklands (1994-present)

Working with Miami-Dade County, we monitored plots for a decade to evaluate how different fire regimes affect pine rockland plant communities. Our findings showed that understory species richness increased with the number of controlled burns a plot received. More species can grow in this habitat if the shrub and tree cover does not get too dense. These results support efforts to conduct prescribed burns in natural areas to improve and protect biodiversity. (Possley et al. 2008)


Demography of rare species (1999-present)

Fairchild conducts demographic studies on several rare species to determine the dynamics of populations. We are particularly concerned to learn whether anthropogenic factors are responsible for declines in the numbers of individuals in a population. Long-term demographic monitoring also helps us understand whether global climate change is influencing rare plant population growth and reproduction.  We currently conduct demographic monitoring on: Jacquemontia reclinata, Dalea carthagenesis var. floridana and Tephrosia angustissima var. corallicola


The effects of installing a weir on the vegetation surrounding Cutler Creek at the Deering Estate (2002-present)

The purpose of this research is to monitor effects of hydrological restoration to the Deering Estate at Cutler.  Prior to installation of a weir, we selected and monitored indicator species that were expected to respond most quickly to altered hydrology.  We focused on ferns given their dependence on water for reproduction. Prior to urbanization, some of the rarest ferns in Florida were found within the Estate, in the hardwood hammock along the limestone embankments of the historic Cutler Slough. A few rare species remain, while others have been extirpated. We hope that rehydrating the slough, which closely approximates historic hydrology, may increase the abundance and diversity of native ferns.


The effects of leaf litter depths on the germination and establishment of federally endangered Amorpha herbacea var. crenulata (2004-2007)

Wild populations of crenulate leadplant (Amorpha herbacea var. crenulata) exist in only two protected Miami-Dade County parks. Habitat destruction, canalization throughout south Florida, and fire suppression have greatly altered their habitats and disrupted flowering, fruit production and seedling establishment. In 2004, Fairchild biologists examined the effects that leaf litter depths had on the germination and establishment of the crenulate leadplant. We found that 2 cm litter depth is most effective for seedling establishment (Wendelberger and Maschinski 2009). This information has helped management.  With land managers, Fairchild Challenge students and the Connect to Protect Network we have worked to restore crenulate leadplant habitat and have helped improve seedling survival (Powell and Maschinski 2012).  


Competitive effects of the invasive grass Rhynchelytrum repens on native plant diversity in a Miami-Dade County pine rockland (2004-2007)

Rose natal grass (Rhynchelytrum repens) is a non-native, invasive grass from South Africa that is naturalized throughout Florida. It has been popular in Florida as landscape plant for its plumes of pink, long-lasting flowers, however the Florida Nurserymen and Growers Association (FNGA) agreed to phase this species out of horticultural trade in 2001. In Miami-Dade County, rose natal grass can be a persistent problem in disturbed pine rocklands. We documented the negative effects of this grass and determined at which density an infestation should be treated (Possley and Maschinski 2006).


Effects of fire surrogates on vegetation structure and community (2001-2003)

In the pine rockland ecosystem, it has been long understood that periodic fire is a critical natural function. Yet, burning pine rocklands in the urban interface is often prohibited or problematic for land managers. To test the effects of a fire surrogate (thinning) on understory biodiversity, we initiated studies in a pine rockland in spring 2002. One year after thinning, treated plots had more native species and a greater diversity of species than either control or reference plots. Thinning treatments increased the abundance of some, but not all rare species. Fortunately, thinning treatments did not increase the density of exotic species in plots. Thus, thinning is an effective tool for maintaining biodiversity of pine rocklands in urban settings (Maschinski et al. 2005).

 


We thank the following agencies for supporting our research.

Florida Dept. of Agriculture and Consumer Services
Florida Fish and Wildlife Conservation Commission
Miami-Dade County
U.S. Fish and Wildlife Service