Honors & Awards
Anne T. and Robert M. Bass Fellowship, Stanford University (2014)
Outstanding Achievement Award for High Impact Paper, Hopkins Marine Station (2014-2015)
Education & Certifications
Master of Science, Oregon State University, Ocean, Earth and Atmospheric Sciences (2014)
Master of Arts, Stanford University, ED-MA (2005)
Bachelor of Arts, Brown University, Mathematics (2002)
How Baleen Whales Feed: The Biomechanics of Engulfment and Filtration.
Annual review of marine science
2017; 9: 367-386
Baleen whales are gigantic obligate filter feeders that exploit aggregations of small-bodied prey in littoral, epipelagic, and mesopelagic ecosystems. At the extreme of maximum body size observed among mammals, baleen whales exhibit a unique combination of high overall energetic demands and low mass-specific metabolic rates. As a result, most baleen whale species have evolved filter-feeding mechanisms and foraging strategies that take advantage of seasonally abundant yet patchily and ephemerally distributed prey resources. New methodologies consisting of multi-sensor tags, active acoustic prey mapping, and hydrodynamic modeling have revolutionized our ability to study the physiology and ecology of baleen whale feeding mechanisms. Here, we review the current state of the field by exploring several hypotheses that aim to explain how baleen whales feed. Despite significant advances, major questions remain about the processes that underlie these extreme feeding mechanisms, which enabled the evolution of the largest animals of all time.
View details for DOI 10.1146/annurev-marine-122414-033905
View details for PubMedID 27620830
Humpback whale "super-groups" - A novel low-latitude feeding behaviour of Southern Hemisphere humpback whales (Megaptera novaeangliae) in the Benguela Upwelling System.
2017; 12 (3)
Southern Hemisphere humpback whales (Megaptera novaeangliae) generally undertake annual migrations from polar summer feeding grounds to winter calving and nursery grounds in subtropical and tropical coastal waters. Evidence for such migrations arises from seasonality of historic whaling catches by latitude, Discovery and natural mark returns, and results of satellite tagging studies. Feeding is generally believed to be limited to the southern polar region, where Antarctic krill (Euphausia superba) has been identified as the primary prey item. Non-migrations and / or suspended migrations to the polar feeding grounds have previously been reported from a summer presence of whales in the Benguela System, where feeding on euphausiids (E. lucens), hyperiid amphipods (Themisto gaudichaudii), mantis shrimp (Pterygosquilla armata capensis) and clupeid fish has been described. Three recent research cruises (in October/November 2011, October/November 2014 and October/November 2015) identified large tightly-spaced groups (20 to 200 individuals) of feeding humpback whales aggregated over at least a one-month period across a 220 nautical mile region of the southern Benguela System. Feeding behaviour was identified by lunges, strong milling and repetitive and consecutive diving behaviours, associated bird and seal feeding, defecations and the pungent "fishy" smell of whale blows. Although no dedicated prey sampling could be carried out within the tightly spaced feeding aggregations, observations of E. lucens in the region of groups and the full stomach contents of mantis shrimp from both a co-occurring predatory fish species (Thyrsites atun) and one entangled humpback whale mortality suggest these may be the primary prey items of at least some of the feeding aggregations. Reasons for this recent novel behaviour pattern remain speculative, but may relate to increasing summer humpback whale abundance in the region. These novel, predictable, inter-annual, low latitude feeding events provide considerable potential for further investigation of Southern Hemisphere humpback feeding behaviours in these relatively accessible low-latitude waters.
View details for DOI 10.1371/journal.pone.0172002
View details for PubMedID 28249036
View details for PubMedCentralID PMC5332018
Hydrodynamic properties of fin whale flippers predict maximum rolling performance.
journal of experimental biology
2016; 219: 3315-3320
Maneuverability is one of the most important and least understood aspects of animal locomotion. The hydrofoil-like flippers of cetaceans are thought to function as control surfaces that effect maneuvers, but quantitative tests of this hypothesis have been lacking. Here, we constructed a simple hydrodynamic model to predict the longitudinal-axis roll performance of fin whales, and we tested its predictions against kinematic data recorded by on-board movement sensors from 27 free-swimming fin whales. We found that for a given swimming speed and roll excursion, the roll velocity of fin whales calculated from our field data agrees well with that predicted by our hydrodynamic model. Although fluke and body torsion may further influence performance, our results indicate that lift generated by the flippers is sufficient to drive most of the longitudinal-axis rolls used by fin whales for feeding and maneuvering.
View details for PubMedID 27591304
Kinematic Diversity in Rorqual Whale Feeding Mechanisms
2016; 26 (19): 2617-2624
Rorqual whales exhibit an extreme lunge filter-feeding strategy characterized by acceleration to high speed and engulfment of a large volume of prey-laden water [1-4]. Although tagging studies have quantified the kinematics of lunge feeding, the timing of engulfment relative to body acceleration has been modeled conflictingly because it could never be directly measured [5-7]. The temporal coordination of these processes has a major impact on the hydrodynamics and energetics of this high-cost feeding strategy [5-9]. If engulfment and body acceleration are temporally distinct, the overall cost of this dynamic feeding event would be minimized. However, greater temporal overlap of these two phases would theoretically result in higher drag and greater energetic costs. To address this discrepancy, we used animal-borne synchronized video and 3D movement sensors to quantify the kinematics of both the skull and body during feeding events. Krill-feeding blue and humpback whales exhibited temporally distinct acceleration and engulfment phases, with humpback whales reaching maximum gape earlier than blue whales. In these whales, engulfment coincided largely with body deceleration; however, humpback whales pursuing more agile fish demonstrated highly variable coordination of skull and body kinematics in the context of complex prey-herding techniques. These data suggest that rorquals modulate the coordination of acceleration and engulfment to optimize foraging efficiency by minimizing locomotor costs and maximizing prey capture. Moreover, this newfound kinematic diversity observed among rorquals indicates that the energetic efficiency of foraging is driven both by the whale's engulfment capacity and the comparative locomotor capabilities of predator and prey. VIDEO ABSTRACT.
View details for DOI 10.1016/j.cub.2016.07.037
View details for Web of Science ID 000385690800022
View details for PubMedID 27666966
- Depths, migration rates and environmental associations of acoustic scattering layers in the Gulf of California DEEP-SEA RESEARCH PART I-OCEANOGRAPHIC RESEARCH PAPERS 2015; 102: 78-89
- An automatic and quantitative approach to the detection and tracking of acoustic scattering layers LIMNOLOGY AND OCEANOGRAPHY-METHODS 2014; 12: 742-756