My name is Kyra and I’m in my final year of undergraduate studies at Bryn Mawr College working in Dr. Record’s research lab. I’m interested in ecology and philosophy of science, specifically in understanding how we can model biological complexity. I’ve been working with Sydne and Rob Salguero-Gomez (Oxford University Department of Zoology) on a mistletoe demography project for about a year now and I recently visited Oxford for two weeks to help with some of the fieldwork.
The cool thing about mistletoe—and one of the reasons it’s important to study—is that it’s hemi-parasitic. This means that the plant can obtain resources both from photosynthesis and from its host tree. At the moment there’s not a lot of data on parasitic plants, but they’re important to understand because their life history strategies may differ from non-parasitic species. For example, because mistletoe plants don’t need to invest as much energy into a root system to obtain water, we might expect them to have more energy to invest in reproduction than non-parasitic plants. The main hypothesis we’re investigating in this study is that mistletoe will demonstrate weaker trade-offs in reproduction and survival than non-parasitic plants.
Investigating this hypothesis involves a lot of tromping around in the woods with various pieces of expensive equipment. On a typical day in the field, Rob, Yash, and I carried two drones, two scopes, at least one tripod, a camera, and two iPads out into the woods looking like a group of over-prepared hikers. Once we arrived at a tree, we would take a picture of it from the same spot the picture was taken last year. This makes it easier to tell which mistletoes have died and which are still on the tree. After we took pictures with the iPad, camera, and drone, we would use the scopes to identify whether the mistletoes had fruit on them to determine whether they were reproductive. And finally, we would scan the tree to find new recruits—young plants that could have only a few leaves.
Back at Bryn Mawr I spend a lot of time in the lab staring at the pictures from the field. Using the software ImageJ I can measure the relative growth of the plants from the pictures we take each year. For the past year I’ve been using these images to gather information on the growth, survival, and reproduction of each individual mistletoe over the course of several years. I’ve started to use these data in integral projection models (IPMs) that will help us to understand the demography of these populations.
One of my favorite parts of doing fieldwork this year was realizing how well I’ve gotten to know each of the host trees. Just from looking at the branching patterns and distribution of mistletoe, I can tell you the ID number of almost all 25 of them. I even have some favorite mistletoe plants (mistletoe number 38 on Tree 128 is especially cute). Spending so much time looking at mistletoe plants on a computer screen has helped me to find even very small plants when I’m out in the field. It’s a very odd skill, but one that I’m very proud to have.
Check out our new paper here from our NASA funded working group: https://onlinelibrary.wiley.com/doi/full/10.1111/geb.13061.
We found that geodiversity variables predict biodiversity more consistently than climate variables, which is interesting because climate is generally thought to be the most important driver of biodiversity. Variability in topography and elevation was the most important aspect of geodiversity for predicting both bird and tree biodiversity. However, the relationships are really most consistent within individual ecoregions of North America. (Ecoregions are areas dominated by a single well-defined ecosystem type; the Nature Conservancy has identified about 70 of them in the contiguous United States.) But the relationships vary a lot across regions to the point where it’s hard to apply geodiversity relationships from one region to another one. What we can say is that trees have a closer relationship to the topography. Places with variable elevations tend to have higher tree diversity but actually lower bird biodiversity. Birds, especially migratory birds, can seek out the highest productivity locations to breed so they are less tied to the topography.
Dr. Sydne Record and colleagues from Harvard Forest published new conceptual framework for identifying, monitoring, and conserving foundation species, with case studies of declining Eastern hemlock and whitebark pine. Check it out here.
“To continue to extend the ecological tent, working group leaders should be deliberate and thoughtful in their conduct.” Sydne and colleagues Kyla Dahlin and Phoebe Zarnetske (both from Michigan State University) reflect on how they worked to increase inclusion while leading a NASA funded working group of 15 scientists in a new article in Frontiers in Ecology and the Environment. Spoiler alert: they propose a new use of toddler toothbrushing and handwashing timers.
Brianna Martinez (BMC ’22 and Houston Posse) did a great job presenting her research from this past summer at Harvard Forest at the Bryn Mawr Summer Science Research Symposium. Way to go, Brianna!
Congratulations to Nia “Blue” Riggins! The Ecological Society of America (ESA) awarded Blue a diversity award as Strategies for Ecology, Education, Diversity and Sustainability fellow. Blue received the award at the ESA annual meeting last week in Lousville, Kentucky. While there, Blue also presented her research in collaboration with Dr. Sydne Record in a poster entitled, “What does the future hold for the Harvard Forest Megaplot? Seedling Abundance, Diversity, and Mortality of a Forest in Transition.” The abstract for Blue’s poster is online here.
Dr. Sydne Record co-authored a paper on the importance of considering geodiversity as an essential component of the Earth system. She and an international group of collaborators emphasize the need for essential geodiversity variables in international global frameworks for conservation. Check out the paper in the Proceedings of the National Academy of Sciences.
Field season is in full swing as the Record Lab embarks on its third season of sampling tree seedlings in the Harvard Forest ForestGEO plot. In June we welcomed colleagues, Dr. Andrew Latimer and Paige Kouba from UC Davis. Paige is staying on at Harvard Forest to help with the census. Fun times!
Kyra Hoerr (BMC ’20) and Dr. Sydne Record co-wrote a successful Global Bryn Mawr grant to study mistletoes in New Jersey and the United Kingdom. The grant will pay for Kyra to do field work next winter in the U.K. with our collaborator Roberto Salguero-Gomez at Oxford. It will also pay for some field work in New Jersey to set up a sister study on mistletoes and pay for Rob to visit Bryn Mawr to give a talk on his awesome COMADRE and COMPADRE global demography databases.
Last week, Dr. Sydne Record had the chance to visit the beautiful National Center for Atmospheric Research (NCAR) in Boulder, Colorado for a meeting hosted jointly by NCAR and the National Ecological Observatory Network. The meetings goal was to work toward greater success in predicting the earth system via greater synergies between ecologists and climate change modelers.