The Sperry Lab

Conspecific attraction is the tendency for animals to settle near their own species. Our research aims to determine the role social information has on conspecific attraction in both birds and anuran amphibians. Acoustic signals play an important role in social communication in birds and anurans, and responses to these cues may vary based on species, sex, age, habitat, and life history. We have experimental field sites located in Indiana and Illinois, which allows us to test responsiveness to vocal cues in a variety of species and habitats. A few example species include Wood Frog, Eastern Gray Treefrog, Grasshopper Sparrow, Prairie Warbler, and Golden-winged Warbler.

In addition to acoustic cues, evidence suggests that amphibians may also use chemical cues for social signaling at shorter ranges. We are performing laboratory phonotaxis and chemotaxis experiments that will allow us to further examine response to chemical cues in a controlled setting.

Results from these experiments should further our understanding of social communication in birds and anurans and potentially contribute to management efforts.

In collaboration with researchers at the University of Hawaii, Northern Arizona University, and University of Wyoming, we are investigating the role of invasive bird species (and rats) in the seed dispersal networks on the Hawaiian island of O'ahu. O'ahu provides a unique system to investigate this topic since there are no more native seed dispersers left on the island. Our goal is to determine if the exotic seed dispersers are effectively dispersing the seeds of the native and exotic plant communities. In addition, we aim to project our findings into the future to answer questions about the long term stability of this novel forest community and how it might change as under differen global climate change scenerios.

To learn more
visit our project website

Wildlife translocations are a popular conservation tool but have mixed success regarding animal behavior and survival. We are exploring if various behavioral conditioning methods improve post-release survival. Current projects include investigating the effects of environmental enrichment and captive-rearing duration on head-started eastern box turtles, and how temporarily holding individuals in acclimation pens at release sites (delayed or soft release) influences survival of wild eastern massasauga rattlesnakes and Puerto Rican boas.

Understanding the temporal and spatial scale at which wildlife move is vital, particularly for ecosystems that rely on connectivity for population stability. This is especially true for the wildlife, such as spotted turtles, that inhabit wetland ecosystems, which are often spatially patchy across a landscape and exhibit seasonal patterns in water levels, resulting in the need for turtles to use several different wetland patches across a season. If anthropogenically-altered landscapes are to be managed for both humans and wildlife, then it’s critical for land managers to consider the behavior and spatial ecology of target wildlife species. Data from this study will provide vital information to conservationists and land managers to understand the drivers of inter-wetland movement and population dynamics of isolated populations, and to develop a landscape ecology approach to spotted turtle conservation and management.

Rat snakes and racers are major predators of bird nests. We investigate the factors that influence nest vulnerability to different predator species using a combination of automated radiotelemetry and video monitoring of nests. Additionally, we study the foraging ecology and activity patterns of each snake species. Using this information we can then project these interactions into a warming world.

Habitat use and activity patterns of endangered snakes (Louisiana Pine Snake and Puerto Rican Boa)
Effects of low-water crossing structures on aquatic organism passage
Distribution and abundance of avian species at Fort Buchanan, Puerto Rico
Use of environmental DNA (eDNA) for surveying aquatic organisms