Thesis Defense by Mason Cole – November 6th

 

"Detecting Feeding and Estimating the Energetic Costs of Diving in California Sea Lions (Zalophus californianus) Using 3-Axis Accelerometers"
A Thesis Defense by Mason Cole

The Vertebrate Ecology Lab

MLML Live-Stream | November 6, 2020 at 12 pm

     There is written evidence that when Mason was in third grade he wanted to be an "adventure biologist!", which sounds like an awesome gig. He promptly forgot this dream and ended up pursuing a pre-med undergrad track (B.S. in General Biology from UCSD in 2010), only to change his mind again after graduating. Drawn by wilderness and adventure, and hoping to somehow stumble upon a fulfilling career choice, he booked it to Chilean Patagonia and wandered northward through mountains, diverse volunteer gigs in conservation biology, and his entire bank account before crawling reluctantly back to California. Two years later, armed with experience in both tough field work and poverty, he was ready to take on grad school!  Through hard work and perfect timing he ended up in Dr. McDonald's Vertebrate Ecology Lab, where he couldn't be happier. It was during this time (2015-2020) that Mason's 3rd grade "adventure biologist!" card was unearthed like a fossil from sedimentary layers of nostalgic keepsakes in his parents' home...COINCIDENCE? I think not.
     Mason's research interests currently include the foraging ecology and energetics of large predators, with ample room for broadening this horizon in the future. Mason is also passionate about scientific outreach, outdoor education, and active conservation (habitat conservation and restoration), and has worked (or is currently working) professionally in each of these avenues.

Thesis Abstract:

Knowledge of when animals feed and the energetic costs of foraging is key to understanding their foraging ecology and energetic trade-offs.  Despite this importance, our ability to collect these data in marine mammals remains limited.  In this thesis, I address knowledge gaps in both feeding detection and fine-scale diving energetic costs in a model species, the California sea lion (Zalophus californianus).  In Chapter 1 I developed and tested an analysis method to accurately detect prey capture using 3-axis accelerometers mounted on the head and back of two trained sea lions.  An acceleration signal pattern isolated from a ‘training’ subset of synced video and acceleration data was used to build a feeding detector. In blind trials on the remaining data, this detector accurately parsed true feeding from other motions (91-100% true positive rate, 0-4.8% false positive rate), improving upon similar published methods.  In Chapter 2, I used depth and acceleration data to estimate the changing body density of 8 wild sea lions throughout dives, and used those data to calculate each sea lion’s energetic expenditure during descent and ascent at fine temporal scales.  Energy expenditure patterns closely followed the influence of buoyancy changes with depth. Importantly, sea lions used more energy per second but less energy per meter as dive depth increased, revealing high costs of deep diving.  Combined, these chapters further our understanding of California sea lion foraging ecology and provide new methods to aid similar future studies.

Mason Cole Presents: Detecting Feeding and Estimating the Energetic Costs of Diving in California Sea Lions (Zalophus californianus) Using 3-Axis Accelerometers

Thirteen students defend thesis research in 2019!

By June Shrestha, MLML Ichthyology Lab

I'm happy to share that we've had a total of 13 students students defend their theses in 2019! Please join me in congratulating the students, and read below to learn a little more about their research.

  • Steven Cunningham, Phycology
  • Amanda Heidt, Invertebrate Zoology
  • Sharon Hsu, Vertebrate Ecology
  • Brijonnay Madrigal, Vertebrate Ecology
  • Cynthia Michaud, Physical Oceanography
  • Elizabeth Ramsay, Phycology
  • Katie Harrington, Vertebrate Ecology
  • Jessica Jang, Pacific Shark Research Center
  • Melissa Nehmens, Pacific Shark Research Center
  • Stephen Pang, Ichthyology Lab
  • Patrick Daniel, Physical Oceanography
  • Heather Barrett, Vertebrate Ecology
  • Sierra Helmann, Biological Oceanography

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Twelve students defend theses in 2018!

By June Shrestha, MLML Ichthyology Lab

Congratulations to the twelve students that successfully defended their theses in 2018!

  • Laurel Lam, Ichthyology
  • Alex Olson, Chemical Oceanography
  • Holly Chiswell, Chemical Oceanography
  • Cody Dawson, Phycology
  • Evan Mattiasen, Ichthyology
  • Tyler Barnes, Geological Oceanography
  • Catarina Pien, Pacific Shark Research Center
  • Natalie Yingling, Biological Oceanography
  • Drew Burrier, Physical Oceanography
  • Jen Chiu, Fisheries and Conservation Biology
  • Anne Tagini, Fisheries and Conservation Biology
  • Suzanne Christensen, Phycology

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Congratulations to our 2017 graduates!

By June ShresthaIchthyology Lab

Congratulations to 14 students who defended their research theses and graduated from our program this year! Student research spanned across continents, taking us from the kelp forests of California, to the deep seas of South Africa, and even Antarctica!

The following students were awarded a Masters of Science in Marine Science:

  • Angela Zepp, Phycology
  • Devona Yates, Ichthyology
  • Maureen Wise, Chemical Oceanography & Phycology
  • Melinda Wheelock, Invertebrate Zoology
  • Kristin Walovich, Pacific Shark Research Center
  • Dorota Szuta, Benthic Ecology
  • Scott Miller, Ichthyology
  • Ryan Manzer, Physical Oceanography
  • James Knuckey, Pacific Shark Research Center
  • Jen Keliher, Invertebrate Zoology
  • Jinchen (Martin) Guo, Invertebrate Zoology
  • Christian Denney, Fisheries and Conservation Biology
  • Paul Clerkin, Pacific Shark Research Center
  • Stephan Bitterwolf, Phycology

Read below to learn more about the graduates' research. Feel free to leave a comment if you have any additional questions!

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Congrats to Fall 2016’s eight new Masters of Science!

By June Shrestha, Ichthyology Lab

Congratulations are in order for the eight students who successfully defended their research theses this past semester (Fall 2016)! Student research spanned from California to French Polynesia, from plankton to marine mammals. Read below to learn about the main points of their research, and if you have any questions or want to get in touch with the recent graduates, please leave a comment!

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