Monitoring Plants and Modeling Populations: Lessons for

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Abstracts Florida Rare Plant Task Force Meeting
April 4, 2012
Jason L. Downing, Florida International University; Miami, FL and Fairchild Tropical Botanic
Garden, Coral Gables, FL; jdown003@fiu.edu
“Oil bees, oil plants, and orchids in Southern Florida”
The spread of exotic oil and orchid bees from Central and South America into southern
Florida may be altering native pollinator-plant interactions in southern Florida, some of which
involve rare and endangered plant species. Our research has shown that newly introduced oil
bee Centris nitida may be changing the established pollinator services of two important native
plants: the locust berry (Byrsonima lucida), which is threatened in Florida, and the cowhorn or
cigar orchid (Cyrtopodium punctatum), a Florida endangered species. It also visits the Brazilian
yellow cowhorn (Cyrtopodium flavum; synonym Cyrtopodium polyphyllum), a known invasive
and close relative of the native cowhorn orchid. Before the introduction of C. nitida, the native
oil bee Centris errans was the sole pollinator of both the locust berry and cowhorn orchid. The
introduced oil bee was shown to be a successful pollinator of the locust berry, but currently it is
still not known whether the introduced bee is capable of successfully pollinating our native
cowhorn orchid. If it can, this might be an unusual case of an introduced species actually
benefitting a rare native species.
Michele R. Dudash, Department of Biology, 1210 Biology-Psychology Bldg. #144, University of
Maryland, College Park, MD 20742; mdudash@umd.edu
“Genetic considerations for preserving and restoring plant species and populations”
Two fundamental genetic mechanisms thought to impact plant species persistence and
recovery are inbreeding and outbreeding depression. Inbreeding depression is when matings
between related individuals produce offspring that are less vigorous compared to offspring
resulting from random outcross matings within a population. Outbreeding depression is when
progeny resulting from matings between individuals in different populations are less fit than
progeny produced from outcrossing within a local population. The evidence for inbreeding
depression is almost universal, however, outbreeding depression is much less well studied and
its prevalence unpredictable. The increase in frequency of habitat fragmentation globally has
led to reductions in local population size, mate availability, and gene flow between populations.
Together these events increase the probability of population divergence and subsequent local
adaptation if isolation persists long enough. Restoration initiatives are also often limited in size
owing to resource constraints. Finally, a mechanism proposed to help facilitate population
persistence is phenotypic plasticity; the ability of a single genotype to alter its trait expression
and performance to variable environmental conditions. I review both genetic phenomena and
explore how they are overcome and/or utilized in management agendas and how they may
potentially interact with plasticity to facilitate population and species persistence.
Joyce Maschinski and Samuel J. Wright, Fairchild Tropical Botanic Garden, Center for Tropical
Plant Conservation, 11935 Old Cutler Rd., Miami, FL 33156, USA.
jmaschinski@fairchildgarden.org and swright@fairchildgarden.org
“Breeding history influences long-term field survival of experimental introductions of
Jacquemontia reclinata”
Building new populations of rare species presents an opportunity to create selfsustaining populations resilient to stochastic events, while testing ecological theory. Concern
about disrupting locally co-adapted gene complexes and outbreeding depression has led to a
“local is best paradigm” for source selection, yet there is little empirical evidence with rare plant
reintroductions to support or refute this premise. Genetic evidence showed that two source
populations had high genetic diversity and were not significantly genetically differentiated,
therefore current guidelines permitted mixing sources. Using progeny from controlled crosses
(control, selfed, sibling, far neighbor, and between-site), we tested whether breeding history
would influence long-term survival of US endangered Jacquemontia reclinata reintroduced
within historic range in 2004 and 2005. By 2011, survival significantly increased with distance
from pollen donor, was consistent across years of the study, and became most apparent after
major stochastic events (hurricanes, drought, and exceptional cold). Mean second generation
progeny did not differ significantly across treatments or sites, though magnitude of variation in
recruitment differed across breeding treatments. Population viability models indicated that at
least at one site, only populations founded with between-site crosses are sustainable. These
studies confirm that using a single population source, especially for reintroductions of the
smallest populations of this species may decrease the likelihood of population persistence and is
not advisable. However prior to population mixing of any species, we advise using decision
trees, reintroduction guidelines, and paying close attention to ecology, life history, habitat
specialization, and dispersal mechanisms of target species to achieve sustainable genetically
diverse reintroduced populations.
Eric S. Menges, Archbold Biological Station, P.O. Box 2057, Lake Placid, FL 33852
EMenges@archbold-station.org
“Monitoring Plants and Modeling Populations: Lessons for Conservation of Rare Florida Plants”
I review the efforts of Archbold Biological Station’s Plant Ecology Program and its
collaborators to use demographic monitoring and population modeling to provide insight into
management of rare plants in Florida. We have monitored several dozen species, some for as
many as 23 years. Monitoring marked plants is straightforward but requires consistent protocols
and a sustained effort. Quantifying fecundity, seed banks, and germination requires more
detailed experiments usually will only be possible to conduct on a few populations and years. I
provide examples of vital rate comparisons (over time, among populations and across
treatments), matrix projection models, and extensions of modeling using Bayesian approaches
and integral projection models. It is difficult to validate such models with rare plants, and most
tests suggest that models cannot be used to precisely predict future population sizes or other
demographic metrics. Instead, models can be used to compare management options and
identify crucial life history stages and ecological processes that can be manipulated to conserve
rare plants. In particular, we have used these approaches to identify optimal fire regimes and
project the potential effects of climate change on Florida species.
Brian Pelc, Restoration Specialist, The Nature Conservancy, 625 North Adams Street,
Tallahassee, FL 32301 bpelc@tnc.org
"Our Fine Land: the importance of invasive species management by the Apalachicola Regional
Stewardship Alliance"
Invasive plants affect the ecology, economy and cultural history of every region they
infest. Florida’s Panhandle is particularly susceptible to these effects due to the high rates of
infestation and the unusually high amount of native biodiversity in the area. While a significant
amount of work has been done on treatment methods, political and jurisdictional boundaries
create obstacles to proper treatment by limiting the reach and varying the methods of
treatment across the landscape. The CISMA (Cooperative Invasive Species Management Area)type of regional alliance has been successful in overcoming these artificial obstacles and
coordinating methods and extent of treatment on public and private property. Recently
renamed Apalachicola Regional Stewardship Alliance (ARSA) CISMA, our cooperative began in
2003 as a regional “Invasive Working Group” with the nearly singular mission of treating
infestations on private lands in an effort to leverage the management work on nearby
conservation lands. Now, we are adapting to the CISMA framework by adding new leadership
structure, broadening our objectives and planning for the long term management of invasive
species across a large geographical region. I will briefly cover some of messaging we use for
community outreach and outline our near and long term goals for the area.
Benjamin A. Sikes, David H. Smith Research Fellow, Section of Integrative Biology, University of
Texas at Austin, Austin, TX, USA 78705; bensikes@mail.utexas.edu
“Monitoring Plants and Modeling Populations: Lessons for Conservation of Rare Florida Plants.
Can Soil Microbes Improve Restoration of Native Florida Scrub Plants and Ecosystems?”
Plant interactions with soil organisms are important factors that determine the
structure and long-term stability of plant communities. Yet the vast diversity of this soil biota
remains a largely untapped resource in conservation and restoration. I detail my current
research using cultured soil microbes to try and improve restoration of native FL scrub plant
species. I have cultured over 300 soil fungal isolates from native FL scrub, degraded scrub and
converted pasture sites then subsequently used these fungi as soil amendments with plantings
of native FL scrub plants. Our data shows that the addition of specific soil fungi can improve the
germination and growth of four native plant species that have germinated thus far. No fungi are
silver bullets for restoration success, with specific fungal benefits depending on the history of
the site (disturbed, pasture, or herbicided pasture), the plant species and the origin of the fungi
used. However, our data show that soil microbial additions can help in the re-establishment of
native plants. This research will establish a conceptual framework and prototype for the use of
native soil biota to help preserve and restore native plants and ecosystems.
Tova Spector, Environmental Specialist II, Florida Park Service, Florida Department of
Environmental Protection, 4620 State Park Lane, Panama City, FL 32408;
Tova.Spector@dep.state.fl.us
“Response of Conradina glabra (Shinners) and groundcover to multiple restoration techniques
in a highly disturbed Florida Sandhill”
Conradina glabra is a rare mint listed as endangered by both the USFWS and the Florida
Department of Agriculture and Consumer Services. It is considered rare due to a limited range
that includes well drained sandhill natural community and its ecotones on the east side of the
Apalachicola River south of the Cody Scarp, in Liberty County Florida. It is further threatened
because its entire limited range has been historically altered by pine plantations and ground
disturbing activities. The Florida Park Service in partnership with The Nature Conservancy is in
the process of restoring 4500 acres of sandhill where C. glabra occurs. This study documents the
status of C. glabra at Torreya State Park and the response of C. glabra to different natural
community restoration treatments that includes flattening windrows, harvesting sandpine,
planting native groundcover and burning.
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