© 2019 by Sarah Winnicki. Contact : sarahkw2@illinois.edu  Proudly created with Wix.com  

I just wrapped up my Master's research on the beautiful Konza Prairie Biological Station (NE Kansas, USA) as a member of the Boyle Laboratory. I have worked on Konza since 2014, studying the abundant prairie songbirds at the site (especially Grasshopper Sparrows). 

Ongoing Research:

The impact of maternal hormones on the growth and development of birds

(fondly known on Twitter as project #GrowBirdGrow)

For my PhD work I will be investigating the ways in which the hormones passed from mom to egg ultimately influence the growth and behavior of bird embryos, chicks, and juveniles. Keep checking in using the #GrowBirdGrow Twitter hashtag as I update everyone on my progress! I'm in the process of ordering eggs to incubate now.



The role of brood parasitism in shaping nestling growth and development strategies

(fondly known on Twitter as project #PrairieBabies)

In my master’s research, I seek to identify the effect(s) of Brown-headed Cowbird (Molothrus ater) brood parasitism on the growth and development of nestlings of three grassland-obligate host species: Grasshopper Sparrow (Ammodramus savannarum), Dickcissel (Spiza americana), and Eastern Meadowlark (Sturnella magna). Previous work on nestling development has illustrated the importance of perceived nest predation risk (e.g. Cheng and Martin 2012) and food availability (e.g. Ricklefs 1993)—in order to identify the variation explained by cowbird parasitism, we need to quantify the effect(s) of and interactions between food availability and predation risk as well. We will locate nests of each of the host species and identify the perceived predation risk, the food available to the nestlings, and the presence and risk of cowbirds at subsets of the total nests. We will then relate these factors to the skeletal growth, development (eyes opening, movement capacity), feather growth, and fat/muscle gain of the host nestlings, which we will calculate from nestling measurements taken every other day. At the conclusion of this study we hope to advance our knowledge of the impact of cowbirds, identify the development strategies that produce highest nest and post-fledge success in cowbird-dominated systems, and provide insight on the past and future evolution of cowbird hosts.

Social interactions do not drive territory aggregation in a grassland songbird


Understanding the drivers of animal distributions is a fundamental goal of ecology and can inform habitat management. The costs and benefits of colonial aggregations in animals are well established, but the factors that result in aggregation in territorial animals remain unclear. Territorial animals might aggregate their territories to facilitate social behavior such as (1) group defense from predators and/or parasites, (2) cooperative care of offspring, (3) extra-pair mating, and/or (4) mitigation of extra-pair mating costs through kin selection. Using experimental and observational methods, we tested predictions of all four of these hypotheses over three years at a tallgrass prairie in NE Kansas, USA. Grasshopper Sparrow (Ammodramus savannarum) males established territories at varying densities, forming clumps of territories in some parts of the site while leaving other apparently suitable areas unoccupied. Despite substantial sampling effort (653 territorial males and 223 nests), we found no support for any hypothesized social drivers of aggregation and found no evidence that aggregation increases nest success. Our results run counter to previous evidence of a strong role for conspecific interaction in shaping territory distributions in Grasshopper Sparrows and other songbirds. These results suggest that territory aggregation may not be adaptive in this population, perhaps due to changing landscape contexts and declining population sizes. (accepted for publication in Ecologycoauthors: S.M. Munguía, E.J. Williams, and W.A. Boyle)

Past Research:

Population biology of Red-winged Blackbirds on the Lake Erie Islands

The Lake Erie Islands (Ohio, USA) provide important stopover habitat for migrating songbirds, but little research has been done to assess the quality of the island habitat for residential breeding songbirds. In order to evaluate habitat quality, we used a mist net mark-recapture technique at five different sites in the Bass Islands, focusing our analysis on the Red-winged Blackbirds (Agelaius phoeniceus) due to their relative abundance. When the health of the blackbirds was compared at each location using a weight on tarsus length index, we found no significant difference in the health of the birds among the locations. The proportion of second-year (SY) to after-second-year (ASY) birds was significantly different than the expected proportion in each community, with second-year birds being much more prevalent in the locations studied. This possibly indicates that the more experienced breeding adults are avoiding our sites due to poor habitat quality. In addition, we observed a 380% increase in the prevalence of pox infections in Red-winged Blackbirds from 2012 to 2013, though more research is needed to assess the effect the infection has on the survivorship of the breeding birds on the islands. (This research project was completed as part of a summer REU program at The Ohio State University's Stone Laboratory with Dr. James Marshall).

The Ideals of Female Sanctity in Merovingian and Carolingian Vitae

My undergraduate history research explored the ways that "holiness" was expressed in texts from Merovingian and Carolingian Gaul (5th-8th century, modern-day France). These saints' lives, or vitae, were written to commemorate the lives of and campaign for the canonization of deceased individuals. As such, they do not provide us with stories of historical reality, but rather give us insight into the values of the writers at the time. Therefore, I use vitae of female saints (especially the pretty awesome St. Radegund and St. Genovefa) to explore the ways gender identity interacted with religion; what language and motifs were acceptable ways to portray women's holiness? How did that change over time? How did gender and religion interact with other sociopolitical realities at the time? Ultimately I argued that these vitae portray a shift from warrior-like, action-based valor stories to passive, introspective piety as time progressed. This change mirrored the rise of the Church in Gaul; in the early Merovingian dynasty the spreading Church valued miraculous visible saints of all genders, representing the power of Christianity to the masses as the Church expanded. By the end of the Carolingian dynasty Christianity was firmly established in Gaul--at this point the Church did not need saints who showcased the incredible power of the religion, but rather saints who exhibited quiet, pious deference to the Church hierarchy. Please note that I have not revised this in years-- there are likely problematic references to a gender binary throughout the text. Read it here by clicking on the purple box!