UW-Green Bay student Kari Petrashek has been awarded this year’s Paul and Thea Sager Scholarship for her research paper, “Northern Saw-whet Owl Fall Migration through Woodland Dunes Nature Center and Preserve in Two Rivers, Wis. from 2000-2008.”
The Sagers, faculty emeriti in Human Biology (Thea) and Natural and Applied Sciences (Paul), established the endowed scholarship in memory of former UW-Green Bay Chancellor Edward Weidner. Petrashek is from Two Rivers and recently graduated cum laude with a degree in Environmental Science and biology. The $500 scholarship is applied to the spring semester — her first as a graduate student in UW-Green Bay’s Master’s Program in Environmental Science and Policy.
The owl species of Petrashek’s research can be found roosting in small, dense conifer trees. Its defense upon discovery is to sit still and not fly, leading people to perceive it as “tame.” The song of the Northern Saw-whet Owl is described as a series of whistled toots. To hear a recording, go to www.owling.com/Northern_Saw-whet.htm#recordings and click on the box.
Well aware of the extensive banding effort at the Nature Preserve near her hometown, Petrashek approached the Woodland Dunes staff about joining in the effort and writing a research paper for her Ecological and Environmental Methods and Analysis course taught by Associate Prof. Amy Wolf.
“I thought that the coolest thing about the research was learning about these beautiful owls from Bernie Brouchoud and the staff at Woodland Dunes, and seeing how dedicated they were to the banding efforts there,” Petrashek said. “It was also great to see how excited they were about getting other people involved and teaching the public about the Saw-whet Owl.”
The birds are captured and banded using mist nets, and checked frequently by the “night gang” (a group of volunteers) from late September to mid-November as they migrate south for the winter. Petrachek joined the group approximately once a week and was taught how to remove the owls from the nets. Her semester-long research project was based on the data collected. It included weight, sex, age, wing chord, date of capture, and molt for each individual owl captured. Data was analyzed to compare the age and sex class differences in the migration through Woodland Dunes with findings of previous studies at other locations in North America.
Below are a few of the findings chronicled in Petrachek’s research abstract:
• Females migrated significantly earlier than males during the nine-year period, but a significant difference in the date of capture between age classes was not found.
• The peak of the migration through Woodland Dunes was found to occur during the third week of October and the migration did not show an irruptive pattern as suggested by other literature.
• A higher proportion of females than males were consistently netted nearly every year.
• Results suggest that there is variation in the migration from year to year and that multiple factors may influence the movement of the Northern Saw-whet Owl, including the possibility of variation due to geographic location.”