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Terrestrial salamanders of the genus Plethodon are among many vertebrates possessing both main olfactory and vomeronasal systems, which the Volatility Theory posits are for detection of volatile and soluble olfactory cues, respectively. Further recent work showing a high amount of convergence between the two olfactory subsystems at the level of the central nervous system suggests complementary or overlapping roles for them. This study examined the use of the olfactory subsystems in prey detection from the perspectives of behaviour and neurobiology. Red-backed salamanders, Plethodon cinereus, were observed in standardized behavioural assays with both volatile and soluble prey olfactory cues. Naïve salamanders showed an increase in nosetapping as well as a side preference in the presence of soluble and volatile prey cues when tested in a 22°C day/20°C night room. In a 15°C day /12°C night room, salamanders increased nosetapping in the presence of soluble prey cues. Salamanders showed a pattern of responses that differed based on their previous experience with the assay, as well as the temperature of the testing room. Attempts to study the neurobiology of olfactory function in Plethodon shermani were inconclusive up to this point, but future directions are discussed. This study shows the importance of olfaction in prey detection by salamanders and that prey searching behaviour is exhibited in the exclusive presence of olfactory cues.

Predation may be a key component of the unsuccessful restoration of the Eastern Oyster (Crassostrea virginica), a former keystone species in Chesapeake Bay. Here, I examine the polyclad flatworm Stylochus ellipticus and its potential role as an important predator of C. virginica. Using small-fragment size C. virginica specific DNA primers, oyster DNA was successfully detected in whole organisms homogenates of wild-caught S. ellipticus individuals. Of the 1,575 individuals tested, 68.1% tested positive, thus predation occurred. Predation did not appear to be affected by salinity or temperature; however, season did appear to have an effect on both predation and S. ellipticus abundance (p-value: <0.05). The findings also imply that S. ellipticus are highly mobile, entering the water column to reach hard substrate at various depths, whereas previous studies suggest otherwise. These findings are useful in the planning and management of oyster cultivation and restoration. Furthermore, this study outlines a method of diet study that may be more sensitive than traditional DNA-based techniques.