It may not be a dark and stormy night, but it is October, so the Northern Research Station is dishing up some of our spookiest science. Meet a scientist who works to help bats (an important and not spooky species) survive a fungal disease that strikes during hibernation; discover what terrifies bird parents, and what the consequences are for nestlings; and learn about a partnership that sought to solve the mystery of dying beech leaves.
Learn about Bat Week, October 24-31, an annual event that celebrates the role of bats in nature.
If it is an animal whose name starts with the letter “B” and interacts with fungi, Michelle Jusino is probably going to be interested in it. As a research biologist, Jusino develops and uses DNA-based techniques to study the relationships that fungi have with bats, birds, and beetles; she has extended these methods to determine the diets of various animals from fecal samples. Jusino began work with the Northern Research Station’s Center for Forest Mycology Research in Madison, WI, in August.
In one of her ongoing projects, Jusino is studying the impacts of the pathogenic fungus that causes white-nose syndrome in bats. This project led to further work answering forest managers’ questions about what two bat species – little brown bats and big brown bats – are eating by using DNA-based molecular techniques to decipher the contents of bat guano.
Jusino is not new to bat guano. As a Forest Service postdoc a few years ago, she led a research team that developed new methods for using DNA analysis of guano and then determined whether the assumption that bats consume a substantial number of mosquitos is true (and it was, research suggested that both the quantity and variety of mosquito species consumed was greater than expected).
It wasn’t bats or even fungi that drew Jusino to a career in science, however. Growing up in Puerto Rico and then in the Southeast, Jusino always had an appreciation for nature but her interest in ecology and conservation was sparked by a high school science teacher. As an undergraduate, Jusino became interested in longleaf pine forests, and once in pine forests she became fascinated by the red-cockaded woodpecker. Her doctoral dissertation centered on the endangered woodpecker’s amazing years-long process of creating a roosting and nesting cavity and how fungi may be involved in helping the birds create it. “It turns out that the woodpecker is helping decay fungi, not just one fungus, but a whole suite of fungi – this was a surprising result, and the question is still if the fungi help the bird?” Jusino said. “That work made me even more interested in fungi and the molecular technologies available for studying them.”
Jusino has been motivated by more than birds and fungi. “It has a lot to do with the people who were mentoring me,” she said. “We all have people who see something in us we don’t see in ourselves.” First as a postdoc and now as a Forest Service scientist, Jusino tries to be that person for the students with whom she works. “It’s great to see them become scientists,” she said.
More about Michelle Jusino >>
Landscapes of Fear – Affecting Parenting in Backyard Birds
When birds are nesting in your backyard you have a front row seat for the hustle and bustle that occurs in the spring when parents are feeding their nestlings. But even though your backyard may feel like a safe haven to you, birds nesting in the yard might be too scared to raise their young to their full potential. A recent study examined how fear of predators can play a role in how often birds feed their nestlings.
A Northern Research Station scientist and University of Massachusetts partners experimentally manipulated the “landscape of fear” by broadcasting recordings of common predators—hawks and owls—then measured the growth of house wren nestlings along an urban gradient that spanned urban, suburban, and rural backyards.
To assess nestling body condition, scientists measured nestling weight every 3 days. They found that even a modest introduction of “scary” predator sounds resulted in nestlings that weighed less, as the parents reduced their feeding rates. Urban nestlings also weighed less than their rural counterparts.
Providing adequate cover and ample food is a key way that homeowners can encourage birds to nest in their yard – and provide a season of entertainment for the homeowner. This can be achieved by retaining large mature trees and planting more native plants to attract quality insects so birds can feed their young.
“Whether people live in the city or countryside, when we landscape our yards with birds in mind, we create welcoming habitats” said Susannah Lerman, research ecologist with the Northern Research Station and study co-author. “These yards can then contribute to conserving populations of some of our favorite backyard species” said Aaron Grade, lead author from University of Massachusetts.
Cracking the Case of the Beech Leaf Disease Mystery
The American beech tree is an easily recognized species with smooth, silver-gray bark and a dense canopy of leaves that brilliantly shimmer gold in the autumn. Valued for its aesthetic beauty, the American beech is also highly prized for its ecological value, providing food and habitat for over 40 species of birds and mammals in the forests of the eastern U.S. However, this iconic tree has suffered significant impact across its range due to removal for agriculture, beech bark disease and most recently by beech leaf disease.
Beech leaf disease was first discovered in Lake County, Ohio in 2012 and a consortium of scientists from federal, state, and local government agencies in the United States and Canada, including the Northern Research Station (NRS), quickly began work to determine the cause of this new threat. In the fall of 2017, the Ohio Department of Agriculture discovered thousands of microscopic worms, called nematodes, on a symptomatic beech leaf, providing an important clue. Northern Research Station Research Biologist Jennifer Koch helped provide evidence that the nematodes did indeed play a role in the mysterious disease. “When healthy American beech seedlings were inoculated with nematodes isolated from symptomatic beech leaves, they, too, developed beech leaf disease symptoms,” said Koch. “Nematodes extracted from these newly symptomatic tissues were confirmed to be the same species found on diseased trees from the field, providing enough evidence to solve the beech leaf disease mystery.”
Scientists continue to collaborate to understand the mechanisms involved in the spread and success of beech leave disease. “We are thankful for the opportunity to work with the Northern Research Station on this important issue” said David Burke, Vice President for Science and Conservation at Holden Forests and Gardens and one of the partners on the beech leaf disease research. “Finding the cause of beech leaf disease is just the first step. Now our work can focus on new treatment and management strategies to combat the disease and keep American beech as a part of our forest landscape.”