Research

Predator-prey interactions are crucial for understanding ecosystem health and conservation initiatives. I am interested in how salamanders respond to predators, determining what external and internal factors affect their anti-predator behavior. 

Effects of diel cycle on anti-predator behavior of Eurycea nana                                                                                                     

         I studied the anti-predator response of Eurycea nana, the San Marcos salamander, to olfactory cues of the green sunfish (Lepomis cyanellus) and to crayfish (Procambarus clarkii). Because the threat of predation is not constant throughout the diel cycle, I wanted to determine whether this differing threat was reflected in shifting antipredator response. 

Effects of turbidity on anti-predator behavior of Eurycea sosorum                                                                                   

           Increased turbidity is increasingly common in aquatic systems in Central Texas due to a variety of anthropogenic effects. I studied the anti-predator response of Eurycea sosorum, the Barton Springs salamander, to olfactory and visual cues of the predatory green sunfish (Lepomis cyanellus) and the non-predatory green-throat darter (Etheostoma lepidum) in turbid and non-turbid conditions. I wanted to determine whether E. sosorum uses multimodal cues to detect predators, and whether turbidity affects their ability to respond effectively to predators. 

Amphibians are often noted for their use as biological indicators for the health of an ecosystem. The state of amphibians can be correlated to the presence of CORT, a stress hormone. Recently, my lab has developed a non-invasive way to measure CORT in aquatic salamanders. I am currently working on a collaborative project comparing CORT levels of Eurycea tonkawae, the Jollyville salamander, from urbanized and non-urbanized streams.  

In my undergraduate work I developed a individual research projects focused on using behavior of the Colorado potato beetle (Leptinotarsa decimlineata) to understand the costs of resistance to neonicotinoids. 

Effects of resistance on olfactory response to leaf odor                                                                                                          

                I compared the ability of a non-resistant population and a resistant population to choose between  using a Y-maze olfactometer. I found there was no significant difference between the populations because they seemed to choose sides indiscriminantly regardless of cue location, implying olfaction may not be important for foraging.  

Toxin sequestration in eggs                                                                                                                                                               

                I looked at whether neonicotinoids can be sequestered in Colorado potato beetle eggs by comparing the response of resistant and non-resistant larvae after being fed eggs laid by females fed treated foliage. This has implications for the use of refuges to decelerate resistance evolution.

Physiological effects of treated foliage on hybrid populations                                                                                              

                We crossed resistant and non-resistant populations and compared the physiological effects (growth rate, mortality rate, molt time) of eating treated foliage on the three populations.

Organic farming methods to attract natural enemies                                                                                                               

                I did summer fieldwork on a research farm in Ithaca, NY looking at the ability of buckwheat (Fagopyrum esculentum) to attract natural predators of the Colorado potato beetle. We found no significant difference in the number or diversity of natural enemies between treatment groups.