As birds and bats flit and fly in the forest preserves of Will County this year, some of them will be scrutinized by researchers looking into the general health and well-being of the creatures.
The research is made possible by the Forest Preserve District’s policy to open up its preserves to select researchers and scientists who need outdoor laboratories for their nature studies.
“Allowing outside researchers access to our properties serves several useful purposes,” said Andrew Hawkins, the district director of planning and development. “And, if researchers are investigating an issue that can assist the Forest Preserve in making more educated decisions toward managing and developing our preserves, then it is in our best interest to allow the researchers access.”
In 2018, two such studies will focus on red-headed woodpeckers and bats.
Olivet Nazarene University researchers are conducting a study on red-headed woodpeckers, and they hope to present their findings at the Illinois Academy of Sciences this spring and the Ecological Society of America in New Orleans this summer.
“Red-headed woodpeckers were once the most common woodpecker in the region,” said Derek Rosenberger, assistant professor at ONU’s department of biological sciences. “However, some evidence indicates that they declined by nearly 90 percent in Illinois in the first half of the 1900s, and then by a further 70 percent in the last 50 years.”
The decline coincided with a drop in the optimal habitat for red-headed woodpeckers, particularly oak savannas and grasslands, Rosenberger explained. “Indeed, less than 1 percent of oak savanna is left, making it a critically endangered ecosystem.”
There is evidence, however, that red-headed woodpecker numbers are stable in some pockets of oak savanna that remain, which should spur more conservation efforts for that type of habitat, Rosenberger said.
“This project was designed to investigate what factors are important in maintaining high populations of these birds,” he added. “If we can discover what factors make some sites better than others, then we can more successfully plan conservation initiatives.”
Rosenberger said the Olivet project also serves as an educational tool for students enrolled in the conservation biology lab he oversees. Kim Zralka, an undergraduate zoology major, conducted surveys and habitat assessments in summer 2017, and she will be doing so again this year as part of her honors thesis at the school.
“She has grown tremendously as a researcher over the last couple years as we planned and implemented this project,” Rosenberger said.
The high quality ecosystems that are found in the Forest Preserve District are crucial to understanding the “rich ecological history of this region,” Rosenberger added. “Supporting research at these sites is critical in gaining an understanding of what we have, what acquisitions and management plans may have the greatest impact, and how we can be the best possible stewards in the future.”
Bat habitat study
The study of bats in Will County forest preserves will be a continuation of research begun in 2016 by the Davee Center for Epidemiology and Endocrinology at Lincoln Park Zoo.
The study team has sampled several forest preserve locations for the past two years and will do so again this year. The point of the study is to find out how environmental stressors are impacting the health and fitness of urban bats, said Matt Mulligan, wildlife research coordinator at the zoo.
“Urban wildlife must adapt to a multitude of stressors from both natural and anthropogenic, or human-caused, sources,” he said. “Physiological measures of stress hormone (glucocorticoid) production in an urban habitat can help us understand these environmental pressures.”
Bats seem to be able to handle brief periods of stress, but long-term stress can cause the suppression of the immune system and drain the bats’ bodies of fat stores and muscle, he said. That could make bats more susceptible to diseases such as white-nose syndrome.
“Certain species of bats are declining at an alarming rate, primarily due to (white-nose syndrome) and scientists are investigating ways to mitigate this decline,” he added.
As part of its research, the team refined bat guano gathering techniques from active roosts and successfully extracted cortisol from the guano. The group also is investigating if urbanization influences the cortisol levels in bats, making them more susceptible to disease.
Mulligan said county forest preserves, along with the Chicago Park District, contain the majority of the remaining green space in the Chicagoland area. “We would not be able to complete our work without the collaborative ties and access from the surrounding forest preserves. Identifying active bat roosts in particular is extremely difficult, so assistance from local ecologists has made that task easier and is greatly appreciated.”
Past district projects
The red-headed woodpecker and bat studies this year are just the latest in a long line of scientific research that has been conducted in preserves, Hawkins said. All proposed research and any other type of work by outside agencies on district land is reviewed by staff, and the work can only take place if the district issues a special use permit. Once the permit is issued, the scientists can get busy.
Past projects have included studies of the endangered Hine’s emerald dragonfly at Lockport Prairie, which led to a better understanding of the insect’s requirements for breeding and its sensitivity to pollution, Hawkins said. This information was used to create better management practices involving prescribed fire and the control of invasive plant species.
And work with rare plants led to a better understanding of how poor reproductive success rates were caused by low levels of cross-pollination, largely from the distances separating individual populations, Hawkins added. This led resource managers to intervene by collecting pollen from different locations and accomplishing artificial cross-pollination. The intervention helped improve reproductive success.
Plant species that were studied included grass pink orchid and spoon-leaf sundew. The group conducting the research was Plants of Concern, which monitors long-term trends in rare plant species. The group also trains citizen scientists to help with its efforts.
Hawkins said sometimes benefits from research conducted in the preserves are direct and sometimes they are more indirect.
“But in the interconnected relationships and process of the natural world, all knowledge is useful,” he said. “We just have to balance the potential benefits against the negative impacts that could result when deciding whether or not to provide access.”