Hailee Leimbach-Maus defends her thesis assessing genetic diversity of invasive baby's breath populations
On July 3, 2018, graduate student Hailee Leimbach-Maus successfully defended her Master's thesis, titled "Genetic structure of invasive baby’s breath populations in a Michigan dune system". Her committee included Dr. Charlyn Partridge, Dr. James N. McNair, and Dr. Timothy Evans.
Hailee's research focused on an invasive plant within dune ecosystems of northwest Michigan. Baby's breath (Gypsophila paniculata) is a nonnative species that is currently invading the dunes of northwest Michigan, as well as elsewhere in agricultural fields and rangelands throughout the northern U.S. and western Canada. It has negative impacts on sensitive native plant species in the Michigan dunes, because it can outcompete them for scarce resources, dominating large dune areas. The dunes in Michigan are a very unique ecosystem, and because of this they are very ecologically and economically important, attracting millions of visitors annually. The Nature Conservancy, the National Park Service and other land management agencies recognize the invasion of baby's breath in Michigan as a management priority, and my research focussed on questions to help them better address this invasion issue.
Hailee sought to estimate the connectivity of these invasive baby's breath populations, so managers can better understand how this plant might be spreading throughout the area, and direct their treatments accordingly. She developed genetic markers called "microsatellites" for this particular species, which allowed her to estimate the genetic diversity in each population, and how they are related to one another or their "structure." Her results indicated that the 12 populations in the study separated into two genetically distinct groups, but even within these two groups, some populations were really isolated, and not very related to one another. These results, along with historical herbarium records, led Hailee to conclude that at least two introduction events in the mid 1900's could have led to the strong population structure that were found in contemporary populations. Additionally, the varied habitat and topography within the dunes could be influencing the relatedness of these populations by isolating certain populations or preventing seeds from dispersing over large dunes. Her results were able to inform the baby's breath management strategy by The Nature Conservancy and the National Park Service at Sleeping Bear Dunes National Lakeshore during their 2018 field season, by advising them where best to focus treatments. Finally, the genetic markers that were developed during Hailee's thesis can be used by other scientists and land managers to help them identify population connectivity elsewhere in the native and invasive ranges of baby's breath.
Hailee is pursuing work that combines her interests in biology, applied ecology and conservation, and pursuing lots of outdoor adventures in and out of work.