Foraging Ecology and Physiology of Leopard Seals
I am working with a team of researchers on an NSF-funded project studying the feeding behavior, ecology, and physiology of an Antarctic top predator, the leopard seal. Our team is made up of researchers from the University of California, Santa Cruz, Sonoma State University, Colorado State University, Baylor University, and the US AMLR program. We completed our first field season in Cape Shirreff, Antarctica in April – May 2018, and we are preparing for our second field season in 2019. You can read more about our work here.
Comparative Feeding Morphology of Seals
Seals have evolved diverse feeding strategies to capture and consume prey. This project documented the cranial and mandibular adaptations associated with different feeding strategies and identified feeding strategies used by extant taxa based on skull morphology. Seals have skull morphologies associated with four feeding strategies—grip and tear feeding, pierce feeding, filter feeding, and suction feeding, with pierce and suction feeding being the most common. The most important variables in determining the feeding strategy of a given species were cranial and mandible shape, prey type, and phylogenic history. This study provides a framework for understanding the evolution and adaptability of feeding strategies used by pinnipeds.
Evolution of Feeding Strategies in Pinnipeds
Little is known about feeding strategies in fossil pinnipeds although adaptations for feeding were crucial to the success of early pinnipeds in their transition from terrestrial to aquatic habitats. We examined the cranial and mandible adaptations for feeding in fossil pinnipeds and showed that fossil pinnipeds used multiple feeding strategies. Most fossil pinnipeds had adaptations for biting, especially more ancestral pinnipeds, which is consistent with their evolution from terrestrial carnivores, and highlights the importance of biting feeding strategies in the transition from feeding on land to in water. We also found that more recently derived fossil taxa had morphological adaptations associated with filter feeding, an aquatic feeding strategy. This study shows that fossil pinnipeds used multiple feeding strategies, and these diverse feeding modes likely allowed them to expand into multiple aquatic niches during their transition from land to water.