I study the ecology of natural populations' responses to environmental change across space and through time.
My dissertation focuses on how local and range-wide drivers shape the occupancy and abundance patterns of a federally threatened, annual plant endemic to granite outcrop pools in the southeastern United States, snorkelwort, Gratiola amphiantha. I conduct annual demographic surveys across the species' distribution to understand what strongly influences the (meta)population dynamics of this species to best inform conservation efforts.
Listen to me geek about my work on this podcast episode:
In Defense of Plants, Ep. 472 - Snorkelwort & Friends are X-Treme!
How does population growth change across climatic niche gradients, with microhabitat characteristics, and across a species' range?
Scientists have long sought to understand what limits species' distributions, leading to canonical hypotheses that emphasize declining niche suitability and reduced habitat availability toward range edges. Yet empirical tests that integrate these hypotheses to explain range-wide patterns of abundance and occupancy remain rare. Using annual, range-wide surveys of the federally threatened snorkelwort, I test how local microhabitat feature and broader abiotic (environmental and spatial) factors jointly shape abundance, population growth, and occupancy.
How do metapopulation dynamics change across the distribution of a naturally patchy plant species?
A metapopulation is a population of spatially isolated subpopulations that persist, as a whole, with dispersal between subpopulations. The occupancy of any one subpopulation may vary across years, making the colonization and extinction rates of subpopulations critical to understanding the metapopulation dynamics.
Snorkelwort, endemic to naturally isolated granite outcrop pools, provides an excellent opportunity to explore metapopulation dynamics in an annual plant system. With annual surveys of pool occupancy, I am quantifying the rates and drivers of colonization and extinction as well as the range-wide metapopulation dynamics of this rare species.
Are cryptic plants more likely to be imperfectly detected than non-cryptic plants?
Imperfectly detecting species presence in the field can lead to underestimates of species’ abundance and distribution. This is well-known in animal systems (Just because we don’t hear an owl, doesn’t mean it isn’t present!) but is under acknowledged in plant systems. Based on a literature review of all papers with published detection probabilities for plants, we found that cryptic plants (annuals with seed banks, geophytes, and deciduous perennials) are more likely to be imperfectly detected than non-cryptic plants. Based on a case study utilizing occupancy models, we then found that snorkelwort has a relatively high detection probability despite being cryptic. However, even with a high detection probability, snorkelwort occupancy was underestimated when it was not accounted for, demonstrating the consequences of ignoring this bias.
How does a dormant seed bank influence snorkelwort's long-term occupancy?
Seed banks can remain dormant in the soil for many years, complicating our estimates of species’ abundance and distribution. While there’s a growing literature incorporating seed banks into demographic models and estimates, it remains understudied and largely theoretical. I’m pairing observational studies of seed bank dormancy with multi-state modeling to understand the role of dormant seed banks in species’ occupancy patterns.
What is the long-term success of granite outcrop habitat enhancement efforts?
The U.S. Fish & Wildflife Service, with many partners, has completed a number of granite outcrop pool enhancement projects aimed at increasing populations of two federally endangered quillworts, Isoetes melanospora and Isoetes tegetiformans. Working with partners, we synthesized these efforts into a comprehensive report and assessed the long-term success of these projects which began in the 1980s. I surveyed inoculated Isoetes populations 6+ years after inoculation to assess abundance and habitat quality, identifying the most successful techniques used across projects. I am now participating in the planning for future U.S.F.W.S. enhancement projects to directly apply what we learned to continue the conservation of rare granite outcrop species.
_edited.png)
What kinds of data are most utilized by plant conservationists and what kind of data is most often published for protected plant species?
Working across institutions, we are conducting a large-scale study in the southeastern United States to better understand the kinds of data used by plant conservationists, the kinds of data published on protected plant species, and the kinds of data required to remove plants from protected status. Our goal is to identify ways to strengthen the connection between research and active, applied conservation efforts.