Dental microwear texture analysis (DMTA) has clarified the dietary ecology of extant and extinct species over the past 20 years, with a focus on terrestrial organisms. The main goal of this study is to assess the effectiveness of DMTA as a tool to interpret diets of the common bottlenose dolphin, orca, beluga whale, walrus, sea otter, and sperm whale. Our preliminary results indicate that marine mammals such as sea otters, beluga whales, walruses and sperm whales eat significantly harder foods (with higher complexity, Asfc values) than the primarily fish consuming common bottlenose dolphin and orca. Additionally, there is little to no evidence that orcas, with the lowest Asfc values, are durophagous (i.e., eating hard foods). There is clear evidence that dolphins and orcas are consuming softer foods than the remaining taxa– which are known to eat invertebrates such as crustaceans and mollusks. Consequently, we found that dental microwear may be an effective tool to analyze the diets of extant and potentially extinct marine mammals, as the surface textures on their teeth correspond with observed diets. Dental microwear texture analysis may allow us to better understand the effects of climate change on marine mammal diets and may be used to track dietary changes from marine mammals in the historical past. It may also be used to potentially aid in developing conservation and management strategies.

Primary Presenter: Ashley Rogers, Vanderbilt University (ashley.d.rogers@vanderbilt.edu)

Authors:

Ashley Rogers, Vanderbilt University  (ashey.d.rogers@vanderbilt.edu)

Dr. Larisa DeSantis, Vanderbilt University  (larisa.desantis@vanderbilt.edu)